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Microneedles in Clinical Practice–An Exploratory Study Into the Opinions of Healthcare Professionals and the Public


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Microneedles are being developed to administer vaccines and therapeutics to and through skin. To date there has been no qualitative or quantitative research into public and health professionals' views on this new delivery technique. Focus groups (n=7) comprising public and healthcare professionals were convened to capture the perceived advantages for, and concerns with, microneedles. Discussions were audio-recorded and transcribed. Transcript analysis identified themes that were explored using a questionnaire identifying consensus or otherwise. Participants identified many potential benefits of the microneedle delivery system, including reduced pain, tissue damage and risk of transmitting infections compared with conventional injections, as well as potential for self-administration (subject to safeguards such as an indicator to confirm dose delivery). Delayed onset, cost, accurate and reliable dosing and the potential for misuse were raised as concerns. A range of potential clinical applications was suggested. The public (100%) and professional (74%) participants were positive overall about microneedle technology. This exploratory research study captured the views of the eventual end-users of microneedle technology. Microneedle researchers should now reflect on their research and development activities in the context of stakeholder engagement in order to facilitate the transfer of this new technology 'from bench to bedside.'
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Microneedles in Clinical PracticeAn Exploratory Study
Into the Opinions of Healthcare Professionals and the Public
James C. Birchall &Rachel Clemo &Alexander Anstey &Dai N. John
Received: 16 December 2009 /Accepted: 23 February 2010
#Springer Science+Business Media, LLC 2010
Purpose Microneedles are being developed to administer
vaccines and therapeutics to and through skin. To date there
has been no qualitative or quantitative research into public and
health professionalsviews on this new delivery technique.
Methods Focus groups (n=7) comprising public and health-
care professionals were convened to capture the perceived
advantages for, and concerns with, microneedles. Discussions
were audio-recorded and transcribed. Transcript analysis
identified themes that were explored using a questionnaire
identifying consensus or otherwise.
Results Participants identified many potential benefits of the
microneedle delivery system, including reduced pain, tissue
damage and risk of transmitting infections compared with
conventional injections, as well as potential for self-
administration (subject to safeguards such as an indicator to
confirm dose delivery). Delayed onset, cost, accurate and
reliable dosing and the potential for misuse were raised as
concerns. A range of potential clinical applications was suggested.
The public (100%) and professional (74%) participants were
positive overall about microneedle technology.
Conclusions This exploratory research study captured the
views of the eventual end-users of microneedle technology.
Microneedle researchers should now reflect on their research
and development activities in the context of stakeholder
engagement in order to facilitate the transfer of this new
technology from bench to bedside.
KEY WORDS clinical practice .healthcare professional .
microneedles .perception .public
Microneedles provide a new opportunity for administering
a wider range of therapeutics to and through skin. Micro-
needles are designed to specific dimensions to facilitate
piercing of the outer barrier layer of skin, the stratum
corneum, to enable drug and vaccine delivery, without
impinging on the underlying pain receptors and blood
vessels. Since the first demonstration that microneedles
were effective in facilitating the delivery of calcein across
the skin (1), there has been widespread academic and
commercial interest in their development, resulting in
extensive research into suitable fabrication methodologies
(27) and potential pharmaceutical and pharmacological
applications (821). Those intimately involved in the
scientific development and testing of microneedles perceive
that this new delivery method will confer many advantages
compared with conventional dosage forms. Indeed, the
literature lists a number of potential advantages of micro-
needles, with specific reference to hypodermic injection,
including pain-free and blood-free delivery (2225), minimal
skin trauma following microneedle insertion (23,26,27),
reduced risk of infection (2729), appropriateness for non-
skilled and/or self-administration (23,3032), reduced risk of
needle-stick injury and cross-contamination (23) and ease of
disposal (27,33,34).
J. C. Birchall (*):R. Clemo :D. N. John
Welsh School of Pharmacy, Cardiff University,
Redwood Building, King Edward VII Avenue,
Cardiff CF10 3NB, UK
A. Anstey
Department of Dermatology, School of Medicine, Cardiff University,
Cardiff CF14 4XN, UK
A. Anstey
Aneurin Bevan Local Health Board,
Newport, South Wales NP20 2UB, UK
Pharm Res
DOI 10.1007/s11095-010-0101-2
Whilst the majority of the literature concentrates on
demonstrating the many perceived advantages of micro-
needles, a few concerns relating to this technology have also
been raised. It has been questioned whether or not the
creation of multiple microscopic holes in the stratum
corneum could allow passage of bacteria, fungi, viruses or
allogenic macromolecules leading to infection or hypersen-
sitivity reactions (28,35,36). It is not known if minimally
invasive delivery methods could provide a risk of inadver-
tent misuse or intentional abuse (35). On a more technical
level, it will also be important to address whether or not
microneedle devices will be able to deliver a sufficient dose
in a reproducible manner (3537).
Despite the extensive scientific research in this field, and the
aforementioned perceptions of those developing microneedle
technology, there has been no qualitative or quantitative
research conducted into the opinion of the eventual stake-
holders of this new delivery technique, that is, those who will
ultimately be prescribing and administering microneedle
injectionsand those who will be receiving them. Whilst
laboratory research must continue to provide further evidence
on the potential clinical applications of microneedles, it is also
important to assess and thereafter consider the views of the
eventual users of microneedles. It is widely accepted that
obtaining public opinion on developing scientific, technolog-
ical and medical innovation and policy is important and that
there should be greater public engagement (3841). Increased
public engagement provides lay citizens the opportunity to
express views, concerns and opinions and to actively
contribute to decision-making processes regarding scientific
advances (42). Public engagement ensures that in the
creation of new technologies, the consumers and potential
consumers do not stand at the end of the scientific pipeline
passively waiting to consume new products. They are agents
in the process of innovation.(43). The United Kingdom
National Health Service (NHS) is currently promoting wider
public engagement in, and involvement with, NHS, public
health and social care research through the National
Institute for Health Research (44).
This preliminary, exploratory study begins to ascertain
the views and opinions of the public on microneedles as a
new drug delivery system. Hopefully, early public engage-
ment will identify the perceived advantages and limitations
of the technology, from the public perspective, and help to
inform microneedle development towards producing an
end product that is acceptable to the public. In addition to
engaging with lay members of the public, this study also
captures the opinions of a range of healthcare professionals,
purposively sampled from a range of backgrounds, regard-
ing the use of microneedles in clinical settings. As well as
providing general opinions and views on the new technol-
ogy, it is anticipated that those involved in parenteral drug
administration will be able to raise more specific and
technical questions than the public through their different
expertise and experiences (4548). For example, the
professional healthcare workers may be well placed to
comment on the potential clinical applications of micro-
needles. This group could also provide a contextual
perspective on appropriate methods and procedures for
administering microneedles in the clinical environment.
In summary, determining the opinions and appropriate
suggestions of the public and healthcare professionals at this
early stage of development will potentially allow microneedle
researchers to recognise and act upon any concerns and realise
potential benefits. This will hopefully aid the successful trans-
lation of microneedles from the laboratory to clinical practice.
Use of Focus Groups
Focus groups can be defined as group interviews that
capitalise on communication between research participants,
in order to generate data(49). The main feature of focus
groups, which distinguishes them from other qualitative
methods, is participant interaction (50). Rather than inter-
views, focus groups were chosen, as they enable the collection
of views from a larger number of participants and allow
individuals to hear and question othersopinions and develop
or modify their individual standpoints. There is greater
participant interaction, with less input (and potentially less
bias) from the moderator, permitting the group participants
to develop and discuss themes that are important to them.
Debates and agreement, or disagreement, can prompt
participants to justify or expand on their points of view.
Thus, focus groups not only allow researchers to examine
what people think, but why they think that way (4951).
Professional Focus Groups
Non-probability purposive convenience sampling was used
to recruit 31 health professionals into three focus groups,
which were held in a UK NHS Trust. The participants
were doctors and nurses from a variety of medical
backgrounds, including accident and emergency, paediatrics,
outpatients (ambulatory care), dermatology, cardiology,
occupational health and general practice. Individual focus
groups comprised of healthcare professionals generally
working in outpatient (ambulatory care) departments (7
participants), accident and emergency (10 participants) and
paediatrics (14 participants) (Table I). Each focus group
commenced with a very brief description of microneedles
from the moderator as a means of focussing the discussions.
This 5 min briefing explained that a) skin has inherent
barrier properties; therefore, many drug molecules are not
Birchall et al.
able to permeate it; b) microneedles are designed to disrupt
the outer skin barrier layer without impinging on the
underlying pain receptors and blood vessels, i.e. their use
may be less invasive than conventional intramuscular or
subcutaneous injections; and c) microneedles can be used by
coating drug onto the microneedle surface, injecting medi-
cine through hollow microneedles or simply using micro-
needles to make holes in the skin after which drug is
delivered via a topical formulation or transdermal patch. A
few images were shown to illustrate the difference in size
between microneedles and conventional needles, and an
example of a microneedle array (36 microneedles of
approximately 300 μm height) was passed around the group.
NHS ethical approval and written consent to take part in the
study and to be audio-recorded was obtained from partic-
ipants prior to the focus group commencing.
Public Focus Groups
Purposive, convenience sampling was used to recruit 27
members of the public as four pre-existing social groups.
Groups were male-only (7 participants), female-only (7
participants) or mixed (two groups of 6 and 7 participants).
The age range was 2053 years with a 12:15 male:female
ratio. Pre-existing social groups were used to encourage
interaction and reduce inhibition when challenging the
views of others (49,51) (Table I). A brief description of
microneedles from the moderator, images of microneedles
and conventional needles and a prototype microneedle
array (as described above) were used as a focussing exercise
for discussion. Ethics approval and written consent to take
part in the study and to be audio-recorded were obtained
from participants prior to each focus group.
Focus Group Data Analysis
All audio-recorded discussions were fully transcribed within
24 h of each focus group. Each participant was assigned an
anonymised identifier, that is, public participants were
identified as PP1 to PP27, and healthcare professional
participants were identified as HP1 to HP31 (Table I).
Focus group transcripts were reviewed, coded and themat-
ically analysed (50,51) to determine the issues to be
explored through the subsequent questionnaire. Exemplar
quotations are provided in the results section of this paper
for each theme. Focus groups are identified as FG1 to FG4
(public) and FG5 to FG7 (healthcare professionals).
Questionnaire Design
Questionnaires were used to further substantiate the outputs
from the qualitative focus groups (52,53), allowing individuals
to express their own opinions where they may have differed
from those of other group members and did not wish to
disagree or where they were not able to express their view
within the group. The questionnaire was also used to raise
issues not fully discussed with all focus groups. The quotations
from the focus groups were used to create an item pool of
attitude statements. Since the attitude statements were wholly
derived from focus group transcripts, this reduced researcher
bias. An attitude statement is a single sentence that expresses
a point of view, a belief, a preference, a judgement, and
emotional feeling or a position for or against something (52).
Quotes from the item pool were modified, as illustrated in the
example below, to improve clarity and allow subsequent
analysis of general agreement or disagreement.
Attitude Statements:
Original transcribed quote from focus group:
Because, if theyre not as effective I would be prepared to go
through pain knowing that I was more likely to be, um, er,
effectively treated than, er, you know, I mean, theres the
epidural, theres no point in having an epidural thats ineffective,
where, so Id be prepared to go through the pain, to have the
pain relief, knowing that it was effective.
Resulting attitude statement:
I would still be prepared to go through the extra pain and have
an injection, if it was more effective than microneedles.(Public
questionnaire, question 11)
Table I Composition of focus groups
Focus group Participant profile Social group / professional expertise No. in group Age range Participant identifier
1 Lay Public Mothers 7 3753 FG1, PP1-7
2 Lay Public Adults without children 6 2027 FG2, PP8-14
3 Lay Public Mixed Adults 7 2237 FG3, PP15-20
4 Lay Public Fathers 7 2653 FG4, PP21-27
5 Healthcare Professional Outpatients (Ambulatory Care) 7 Unknown FG5, HP1-7
6 Healthcare Professional Accident & Emergency / Occupational Health 10 Unknown FG6, HP8-17
7 Healthcare Professional Paediatrics 14 Unknown FG7, HP18-31
Microneedles in Clinical PracticeAn Exploratory Study into the Opinions
A number of such attitude statements were created in
the form of a five-point Likert scale which allowed
participants to tick one of the following options for each
statement: strongly agree, agree, no opinion, disagree or
strongly disagree (52). The attitude statements included
statements that were both for and against the use of
microneedles to ensure the questionnaire itself was not
inappropriately weighted in favour of, or against, micro-
needles. In addition to attitude statements, participants
were also asked for more general views. Questionnaires
were provided to all 58 participants approximately 4 weeks
after they had taken part in the focus groups.
Focus Group Studies
In this study, qualitative methods were employed to explore the
views of the public and professionals on the microneedle drug
delivery system. Qualitative methods are more appropriate for
initial exploratory research, as they help us understand
phenomena in natural settings, giving due emphasis to
experiences and views of the participants; provide access to
areas not amenable to quantitative research, such as lay and
professional health beliefs; lead to the generation of hypotheses,
as opposed to the testing of hypotheses; establish the views of
those being researched, rather than the views of the researchers;
and act as an essential pre-requisite to reliable quantitative
research, particularly in areas with little prior investigation.
Data from this preliminary qualitative research could therefore
be used to supplement larger-scale quantitative research
including obtaining the views of those who will be involved in
distributing these devices, e.g. pharmacists. Focus groups were
identified as the appropriate qualitative methodology for
exploratory research into public and professional perceptions
regarding microneedle technology and applications (4551).
The potential advantages of microneedles as a new drug
delivery system, identified from comments raised by both
public and professional focus group participants, are listed
in Table II. Exemplar comments are included below with
the focus group and participant identifiers. All of the groups
highlighted the fact that, in their view, microneedles would
cause less pain on administration, thereby providing an
attractive alternative to conventional injection, particularly
in situations where injection pain is an important factor, for
example, paediatric medicine, needlephobia and for treat-
ment of certain chronic conditions, such as diabetes.
Focus Group (FG)2, Public Participant (PP)10: If they
are just as effective as conventional needles and they are less
painful, as long as they are not more expensive, I suppose people
would always choose them over conventional needles.
FG1, PP3: It would be good for children wouldntitwhen
you are taking your children, knowing that they dont have to
suffer the same, suffer as much pain as when the injection goes in.
FG3, PP18: I think theres, theres probably quite a number of
people who really dont like the pain of injections, and who are
scared to go, and therefore will avoid having vaccinations, and I
think if they knew it was going to be really pain-free, then
hopefully a bigger range of people would actually come and have
vaccinations they need.
FG7, HP20: We get lots of adults leaving the room because
they cant look at needles; theyre quite needle-phobic.
FG5, HP3: As a GP I would say probably, in the area of chronic
disease, painless, empowering patients, certainly things like diabetes,
maybe helping people with terminal illness control their own pain.
FG6, HP10: It would be better for travelling as well; you
wouldnt have to take piles of syringes and needles and everything
else there isyou could just take a little box with everything in
and just put it on when you, when you have to.
Potential advantages of microneedles Public Professional
Reduced pain on administration √√√√√√√
Good for children √√√√√√√
Good for needlephobes √√√√√√√
Good for diabetics √√√√√√√
Ability to self-administer with minimal training √√√√√√√
Reduced needle-stick injuries √ √ √√√
Alternative to oral medication √√√√√
Potential for controlled release and delivery √√√√
Reduced apprehension to injection √√ √
More discreet method for delivery √√√
Table II Potential advantages
of microneedles. Potential
advantages were identified
following thematic analysis of
focus group transcripts
Birchall et al.
During each focus group, whether comprising public or
professional participants, the potential advantage of self-
administration was raised. It is clear that the focus group
members believed, without any prompting, that a mini-
mally invasive microneedle delivery device may be able to
be administered given very minimal training and that
administration would not necessarily be restricted to a
clinical environment. It was interesting to note, however,
that the public groups raised a number of concerns relating
to self-administration. A number of participants indicated
some discomfort about the responsibility of using the device
properly, on themselves and their children, to deliver an
appropriate dose. Public participants also sought reassurance
on the appropriate safe disposal of a used microneedle device.
The professional participants, however, did not raise any
concerns on self-administration, describing only perceived
advantages over conventional injections.
FG4, PP23: Just looking at it, youre not going to have to be
as well trained to inject that, so you would have thought Joe-
public would be able to do that themselves.
FG2, PP10: I would rather have it done by a doctor as well,
because I would be thinking that something might have gone
wrong, or I hadnt done it completely correctly. I think people still
believe in doctors and nurses more than they do their own ability.
FG6, HP11: It would be easier for patients to learn to use
themselves, you know, perhaps in cases with fertility drugs and
things, where patients have got to go home and inject themselves.
The participants recognised that a current problem with
conventional needles is the risk of transmitting infection
through needle-stick injury. Whilst both the public and
professional groups recognised that microneedles could
offer less risk of cross-infection, the professional participants
in particular regarded this as a major advantage that
potentially addresses a surprisingly common and under-
reported adverse event (54).
FG1, PP3: Also would theybe safer, if you accidentally prick or if
the person administering it would accidentally prick themselves,
would that be a safer way maybe than a traditional type of needle,
you know theres these sort of needle-stick injuries arent there?
FG7, HP19: Is there any advantage in needle-stick injuries?
Because we get quite a lot of those at the moment.
FG5, HP1: Presumably theres no transmissible infection risk
because youre not actually being exposed to any blood products,
are you?
Table II shows some additional advantages that were
predominantly raised during the professional groups (FG4-7).
These advantages were more technical in nature, when
compared with public comments, such as the use of micro-
needles as an alternative to oral medication, especially for
children, and the potential for achieving controlled release via
microneedle delivery.
FG7, HP21: Some children get really cross with oral
medication and spit it out, and then theyre not taking anything
else. Im looking after a child now and he will NOT take
anything in his mouth, and hes like No medicine,so if you
can give it pain-free somewhere else, you know theyre getting it.
FG5, HP4: One of the major advantages could be the slow
delivery of drugs over a period of time.
The most frequently raised concerns during the focus
groups are shown in Table III, which demonstrates that, in
general, the public and professional groups raised many
similar concerns regarding microneedle technology.
All of the groups required reassurance that microneedle-
based drug administration would be sufficiently efficacious
and rapidly acting.
FG1, PP1: Because, if theyre not as effective, I would be
prepared to go through pain knowing that I was more likely to
be, um, effectively treated.
FG4, PP21: I wonder whether the microneedle will be as effective
with it being injected only on the top layer. Is the microneedle as
effective as something thats going to be injected deeper?
FG4, PP22: If I was really ill and I had a really nasty
disease, I would want whatever got the thing into my system the
quicker to make me better quicker.
FG5, HP2: Do you actually know how long its going to take
for the drugs to get into the system to act?
Interestingly, all of the groups mentioned that it would be
necessary to include a feedback mechanism into the delivery
system that provides the administrator or recipient of the
treatment with confirmation that the appropriate dose had
been administered. These comments can also be linked to the
aforementioned commentary concerning public reservations
about self-administration using microneedle devices.
FG2, PP8: Is there any way to tell its been used? Is there some
sort of coating youd put on, or something that changes colour or
something like that? Just because they are so sensitive you
wouldnt know if you had used it or not.
FG6, HP8: So youre giving, say, 1 ml of something into a
muscle and you know youre going deep, and you can be quite
confident that all the volume has been delivered. I just feel a bit
uncomfortable with managing a very small volume into the skin,
and not being able to see exactly if its actually being delivered.
FG7, HP18: The fluid you were giving, if it was dyed, or
something, so it wasnt harmful to the skin, but you could see the
point of entry of just tiny dots, then you would know obviously if
youd touched it on yourself, you could see the area.
Microneedles in Clinical PracticeAn Exploratory Study into the Opinions
The potentially higher cost of the device, when compared
with existing oral and injectable systems was mentioned within
the groups.
FG4, PP22: You know the health service is, in terms of cost,
its absolutely crucial isnt it, because this could deflect attention
from more needed treatments, or other people.
The public participants were particularly perceptive and
inventive when considering ways this new technology may be
misused or abused. For example, it was questioned if the risk of
accidental cross-contamination may be increased, as the
devices would be perceived to be less dangerous than
conventional needles and provide a less obvious hazard.
Similarly, it was noted that the minimally invasive nature of
the microneedle device could allow the devices to be
intentionally misused to deliver a harmful substance without
the recipientsknowledge.
FG2, PP9: Do you not think there could be more of a potential
risk then of people injuring themselves with them or cross-
contamination, say, in the hospital you can see the needles
obviously so you are more aware of the risk of hurting yourself or
somebody with them, whereas with those you wouldnt
necessarily feel that youd even hurt yourself with them.
FG2, PP10: I mean you do worry about the misuse with
abusers of drugs and stuff; theyd probably find it easier to get a
fix through using one of them than like a proper needle.
FG4, PP23: I was always too scared to inject a needle into me,
but if I could have had a little pop with something a bit more
easy I might have well had had a go.
FG3, PP17: You could just, you know instead of having to slip
something in someones drink, and they wouldnt feel it would
they, yeah?
FG3, PP15: Yeah, like that rape drug, you could have
problems with that.
FG2, PP10: I know this is going to extremes, though, but like
terrorists using themor you could get crazy doctors giving their
patients something and you wouldnt know! And theydjusthaveit
on the end of their finger! And just shake your hand and youre dead!
Whilst the issue of potential abuse appeared to be of
greater concern to the public, there were additional concerns
highlighted only by professional participants. Indeed, the
healthcare professionals (FG4-7) were found to have a greater
number of concerns than the lay public. As with the additional
advantages raised by the professional cohort (Table II), the
additional concerns raised exclusively during the professional
groups were more technical or applied in nature (Table III).
These issues included the potential for increased infection
through compromising the stratum corneum, inconsistency
and irreproducibility of skin puncture and delivery given
differences in epidermal thickness between individuals and
within individuals at different skin sites and the practical
difficulties in delivering small volumes of medicament to
restricted biological compartments.
FG5, HP2: One of the major problems that I can see really is
the risk of infection. The skin is a protective layer, and once you
breach it, you breach that protective layer.
FG6, HP9: Do you have to adjust the needle length to the size of
the patient? And would be easy for us to work out, on the shop floor?
FG6, HP8: I just feel comfortable giving a bigger volume of
something, because it, it seems easier to manage.
FG7, 7HP19: But if you were to concentrate drugs, then there
would be more potential for error in children with the dose that
youre giving them, and thats a big consideration.
The use of questionnaires allowed some quantification of
the overall consensus, or otherwise, on themes that had
emerged during the focus groups, making it possible to
Concerns regarding use of microneedles Public Professional
Lack of efficacy √√√√√√√
Delayed onset of action √√√√√√√
Inability to confirm delivery of dose √√√√√√√
Relatively high cost √√√√ √√
Potential for misuse and abuse √√√√√ √
Potential for cross contamination √√√ √√
Inter-individual variation in skin thickness √√
Difficulty in injecting a small volume √√√
Increased risk of infection √√
Restricted availability √√
Ta b l e I I I Concerns regarding
the use of microneedles. Con-
cerns were identified following
thematic analysis of focus group
Birchall et al.
identify whether or not the majority of participants agreed
or disagreed with the issues discussed. The use of an
additional approach for gathering data on the participants
opinions on microneedles also increased research validity
through triangulation (55).
High response rates for questionnaires were achieved,
namely 93% for public participants and 74% for the
healthcare practitioners. Table IV summarises the public
participantsresponses to the listed attitude statements. The
concerns regarding the technology generally aligned with,
and substantiated, those voiced during the focus group
sessions. For example, a suggestion arising from the focus
groups that an indicator would be needed on the device to
show the user that the dose had been delivered correctly was
supported (strongly agree or agree) by 100% of the partic-
ipants. 96% of the participants also agreed that they would
prefer a painful conventional injection if it were more effective
than microneedles. In total, 80% of the participants were also
concerned that drug users could misuse the devices and leave
them in public places. Regarding the potential advantages of
microneeedle use, all of the participants agreed (strongly agree
or agree) that microneedles would be particularly useful in
needlephobic patients and in patients who have to inject
frequently. A high percentage of public participants (92%)
also agreed that microneedles would be ideal for the
administration of medicines to children. These responses
provide strong consensus for focus group observations that
children, needlephobes, and those injecting frequently (e.g.
diabetics), would particularly benefit from the clinical trans-
lation of microneedles.
The focus groups had previously revealed that some
members of the public were particularly wary about self-
administration. The questionnaire, however, highlighted a
more optimistic viewpoint on self-administration, with 88%
of participants agreeing that they would be happy to use
microneedles on themselves, as long as the instructions
provided were clear. Moreover, the majority of participants
(80%) disagreed with the statement I dont think I would want
to administer microneedles to a child in my care,suggesting a
willingness to administer microneedle injectionsto chil-
dren. Providing further evidence of support for self-
administration, when public participants were asked to tick
the most important advantages of microneedles compared
to conventional needles, 84% of participants ticked the
ability for patients to self-administer(Fig. 1). Conversely,
however, when public participants were asked to indicate
how they would like to see microneedles being used in the
future, only 25% wanted the devices to be available from a
pharmacy for subsequent use at home and only 8%
favoured the general sale of microneedles for home use,
Table IV Public participant responses to attitude statements. Percentage of public respondents who strongly agreed, agreed, had no opinion, disagreed
or strongly disagreed with the listed attitude statement
Question Strongly
Agree No
Disagree Strongly
If microneedles cost more than conventional needles, I dont think they are a good idea. 8 24 4 56 8
The NHS should not fund the use of microneedles at the expense of other treatments. 12 36 4 48 0
It is a concern to me that drug users could leave microneedles lying around in public places. 20 60 4 8 8
Microneedles will be more open to abuse than conventional needles. 8 36 24 20 12
With microneedles, it might be hard to know whether you have actually administered
the medicine.
12 72 8 8 0
Microneedle devices should contain an indicator to show when a dose has been administered
64 36 0 0 0
Id be quite happy to use microneedles to administer medicines to myself given clear instructions. 44 44 0 12 0
If asked to use microneedles at home, I would be worried I wouldnt do it right. 0 28 12 56 4
If people could self-administer using microneedles, it could save the NHS time and money. 24 56 12 8 0
I do not trust microneedles to effectively deliver medication at the right dose. 0 16 32 40 12
I would still go through the extra pain and have an injection, if it was more effective
than microneedles.
12 84 0 4 0
If given the choice, I would prefer to be injected with microneedles than traditional needles. 24 36 28 8 4
If given the choice I would prefer to take a tablet than use microneedles. 16 32 20 28 4
If given the choice, I would prefer to use a normal patch than use a patch containing
8203632 4
Microneedles would be good for people who need to inject frequently. 64 36 0 0 0
Microneedles would be better than conventional needles for administering medication
to children.
48 44 8 0 0
Microneedles would be particularly useful for people who are frightened of needles. 64 36 0 0 0
I dont think that I would want to administer microneedles to a child in my care. 4 8 8 72 8
Microneedles in Clinical PracticeAn Exploratory Study into the Opinions
with 75% and 83% of the public participants favouring the
use of microneedles by trained healthcare professionals in
either a hospital or surgery, respectively (Fig. 2). This issue
may, however, not be restricted solely to self-administra-
tionbut also relates to concerns raised during the public
focus groups (Table II) regarding restricting the availability
of the devices to prevent intentional misuse of the device.
Table Vshows the healthcare professional responses to the
listed attitude statements. Inadvertent cross-contamination
with microneedles in the clinical setting was a concern, with
84% of participants agreeing There could be a risk of health
professionals accidentally brushing against microneedles and injecting
themselves.All participants therefore recognised that educa-
tion would be required to prevent cross-contamination with
these new devices. Despite these concerns, Fig. 1shows that
three quarters (75%) of the professional participants consid-
ered the reduced risk of needle-stick injury with microneedles
compared to a hypodermic needle as a key advantage,
compared with a lower proportion of public participants
(57%). It is perhaps unsurprising that practising clinicians and
nurses would consider avoidance of needle-stick injury as
more of an advantage than the general public, as the former
would be at a greater risk of such adverse events.
In agreement with the public participants, the professional
respondents agreed (95%) that an indicator would be required
to confirm that an appropriate dose had been administered to
patients (Table V). Despite not being extensively discussed
during the professional focus groups, 84% of health profes-
sionals thought that there could be a risk of infection with
microneedle use. The same percentage of participants also
agreed that it may be physically difficult to administer liquids
through hollow microneedles given their restricted dimen-
sions, whereas 90% of the healthcare professionals confirmed
their confidence in conventional intra-muscular injection for
delivering appropriate volumes of material. Nevertheless,
95% of the professional participants confirmed that needle-
phobia is a significant problem in the clinical setting.
Both the public and professional participants were asked
to provide their views on the likely future use of micro-
needles (Fig. 3). Specifically, the public participants were
provided a number of options (previously identified in the
public focus group transcripts) to tick following the question
How would you like to see microneedles being used in practice?.
The healthcare professionals were asked to tick up to five
listed applications (previously identified in the professional
focus group transcripts) for which microneedles would be
most useful. It is interesting to note that both public and
professional respondents felt that suitable applications for
the technology include insulin delivery for diabetes and the
minimally invasive delivery of vaccines, although the public
participants clearly felt that the advantages were greater for
childhood rather than adult immunization.
Both groups were also asked to indicate which micro-
needle delivery method they would most like to use at home
(public participants) or which microneedle delivery method
would be of most use in the clinic (professional partic-
ipants). Figure 4shows that there was no clear consensus of
preference for the method of receiving medication using
microneedle technology, although it was noticeable that the
healthcare professionals showed more preference for using
hollow microneedles in conjunction with a syringe when
compared with the public volunteers. It is perhaps
understandable that healthcare providers may want a new
delivery technology to be closely aligned with conventional,
well-practiced and proven delivery methods, such as
Percentage participants
Given by health
professional in a
hospital settin
Given by health
professional in a
doctor's sur
pharmacies for use
Available in
at home
supermarkets for
Available in
use at home
Fig. 2 Future availability of microneedles. Percentage of public participants
who selected the underlying option when asked the following question: How
would you like to see microneedles being used in the future? (Please tick all that
Percentage participants
Less pain
Self Less bleeding Less scarring
and tissue
Less needlestick
Fig. 1 Perceived advantages of
microneedles. Percentage of
public (black bars) and healthcare
professional (grey bars) participants
who selected the underlying
option when asked the following
question: What, if any, would be
important advantages of
microneedles compared to
conventional needles? (Please tick
all that apply).
Birchall et al.
Table V Healthcare professional responses to attitude statements. Percentage of healthcare professional respondents who strongly agreed, agreed, had
no opinion, disagreed or strongly disagreed with the listed attitude statement
Question Strongly
Agree No
Disagree Strongly
Microneedles will not replace all injections. 63 37 0 0 0
In emergencies, it does not matter if you cause pain to that patient, the important thing is getting
the drug administered as quickly as possible.
47 42 0 0 11
It might be harder to physically push liquid through microneedles because the needles are small. 5 79 11 5 0
When you inject deep into the muscle, you can be confident that all the volume has been
16 74 5 5 0
Compared with normal needles, I would not be confident that I had delivered the correct dose
of drug when using microneedles.
26 26 16 26 6
There could be a risk of health professionals accidently brushing against microneedles and
injecting themselves.
37 47 11 0 5
Education would be important to prevent possible cross contamination with microneedle use 74 26 0 0 0
Microneedle devices should contain a visual (or other) indicator to show when a dose has been
administered correctly.
79 16 5 0 0
A potential problem of microneedles is the risk of infection as the skin is a protective layer. 11 73 5 11 0
Needlephobia is a significant problem in the clinical setting. 68 27 0 5 0
Microneedles would be particularly useful for people who are frightened of needles. 74 26 0 0 0
Percentage participants Percentage participants
Patients unable to
swallow oral
Alternative to oral
medication medication
Vaccination Patients on many
oral medications
Patients frightened
of needles
Dental injection
Adult vaccinations
Psychiatric medication
Analgesia in palliative
Dental injections
Insulin injections
Travel injections
Fig. 3 Future clinical applications
of microneedles. Percentage of
public (A) and healthcare
professional (B) participants who
selected the underlying option-
when asked the following
question: Public participants
How would you like to see micro-
needles being used in practice?
(Please tick all that apply). Health-
care professional participants
Please indicate up to FIVE
applications which you think would
be most useful by ticking the
appropriate boxes.
Microneedles in Clinical PracticeAn Exploratory Study into the Opinions
transdermal patches and needles and syringes. On reflec-
tion however, it is also possible that the public groups may
not have sufficient technical or experiential knowledge of
the suggested delivery methods to make an informed
judgement on this particular question.
Finally, both of the groups were invited to provide an
overall view on microneedle technology. Figure 5shows
that all (100%) of the public participants were positive
about microneedle technology, with 28% being strongly
positive. Therefore, despite the many concerns raised, the
public appeared to welcome the potential value of this new
technology. Whilst the majority of healthcare professionals
(74%) were either positive or strongly positive, the remain-
ing 26% were neutral. These neutral participants may see
limited value in the technology at present or at least require
convincing of its worth as a new drug delivery modality.
Importantly, although the results from this exploratory
study may not be generalisable, not one participant was
negative regarding the concept of microneedle devices as a
drug delivery approach.
In this study, we sought to determine the views, opinions
and perceptions of the public and healthcare professionals
relating to the use of microneedles in clinical practice.
The public participants suggested many potential benefits
of the microneedle delivery system, including the reduction
in pain and potential for reduced tissue damage on
administration. These benefits were thought to be particu-
larly important for children and needlephobic patients and
for managing chronic conditions, such as diabetes. In
addition to these perceived advantages, a number of
concerns were also expressed, such as confidence in the
effectiveness of delivery, delayed onset of action, increased
cost and reliable dosing. The potential for microneedles to
be intentionally misused was also a real concern for the
public participants, with participants generally expressing
concerns on making the devices freely available.
The public participants regarded self-administration of
microneedle treatments as a potential advantage, for
example, in reducing hospital or clinic visits. However,
many participants were wary of self-administering medica-
ments and vaccines, unless an infallible method of admin-
istering the correct dose could be developed. Moreover,
participants felt that it would be difficult to confirm
whether a dose had been administered correctly with
microneedles, and, therefore, an in-built dosing indicator
would be required to reassure patients.
The healthcare professional participants reported a wide
variety of advantages with microneedles when compared
with existing delivery techniques. This group also identified
a wide range of potential clinical applications for micro-
needles in both acute and chronic medicine. In common
with the lay public, the professional participants perceived
that microneedles could be particularly useful in needle-
phobic patients and in paediatric medicine. Further, they
welcomed the possibility of delivering a wider range of
medications at a controlled rate, with a reduced risk of
transmitting blood-born infections.
The concerns raised during professional groups included
the need for reassurance regarding the effectiveness of
delivery, speed of onset, inter-individual variation and the
ability to deliver an accurate dosage. Professionals were
apprehensive about the possibility of inadvertently injecting
themselves during practice and the inability to determine
whether they had actually administered a dose to them-
selves (inadvertently) or to their patients (intentionally).
They also regarded a visual dose indicator to be integral to
the finished microneedle product and appeared to welcome
Percentage participants
coated with
with topical
cream or gel
linked to a
None of the
Fig. 4 Method of microneedle administration. Percentage of public (black
bars) and healthcare professional (grey bars) participants who selected the
underlying option when asked the following question: Public participants
Which of the following delivery options would you most like to use at home?
(Please tick all that apply). Healthcare professional participantsWhich of
the following options would be of most use in clinical practice? (Please tick all
that apply).
Percentage participants
Positive Neutral Negative Strongly
Fig. 5 Overall opinion on microneedle technology. Percentage of public
(black bars) and healthcare professional (grey bars) participants who
selected the underlying option when asked the following question: What is
your overall view of the concept of microneedle technology? (Please tick ONE
box only).
Birchall et al.
a microneedle device that was either incorporated into a
transdermal patch or could be linked to a conventional
syringe. More practical concerns related to the logistics of
injecting a smaller, potentially more concentrated dosage
which could be associated with greater risk of error. The
risk of infection was also mentioned, as microneedles could
compromise the skins natural defense barrier against
foreign bodies. It is fair to say that more professional
participants expressed reservations overall, with a quarter
of those responding to the follow-up questionnaire having
only a neutral view on microneedle technology.
Although this novel, exploratory study involved a
relatively small but diverse number of participants, the
combination of qualitative with quantitative social science
research methods established some of the issues that matter
most to the eventual end-users of microneedle devices, that
is, the clinical staff that will deliver microneedle injections
and members of the public who may receive them. It will
be important for the microneedle research community to
reflect upon their research-and-development activities to
consider these issues in an attempt to encourage stakeholder
engagement and facilitate transfer of the concept to the
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... Another technique known as inkjet printing [7] has been introduced recently as a promising method for precise drug processing. This approach often involves the coating of microneedle arrays [10][11][12][13][14][15] with drug binder and drug-polymer solutions at various ratios. The controlled release of a variety of drug compounds is facilitated by 3D printed drug delivery systems [4][5][6][7]. ...
... Solid microneedles are small-scale needles that enter the skin, allowing medication to then be applied. These can be made of any material capable of piercing the skin, including but not limited to silicon, metals, or polymers [15]. Solid microneedles assist in the transport of topically applied drugs across the skin [25]. ...
... Another way to design microneedles is to make them hollow, so drugs can be injected into the circulation of the skin. Although most like hypodermic needles, they are much more accepted [15]. Using hollow needles, drugs are actively transported into the skin circulation with force instead of via passive diffusion as with solid or coated needles [30]. ...
Full-text available
Introduction: Despite their effectiveness and indispensability, many drugs are poorly solvated in aqueous solutions. Over recent decades, the need for targeted drug delivery has led to the development of pharmaceutical formulations with enhanced lipid solubility to improve their delivery properties. Therefore, a dependable approach for administering lipid-soluble drugs needs to be developed. Areas covered: The advent of 3D printing or additive manufacturing (AM) has revolutionized the development of medical devices, which can effectively enable the delivery of lipophilic drugs to the targeted tissues. This review focuses on the use of microneedles and iontophoresis for transdermal drug delivery. Microneedle arrays, inkjet printing, and fused deposition modeling have emerged as valuable approaches for delivering several classes of drugs. In addition, iontophoresis has been successfully employed for the effective delivery of macromolecular drugs. Expert opinion: Microneedle arrays, inkjet printing, and fused deposition are potentially useful for many drug delivery applications; however, the clinical and commercial adoption rates of these technologies are relatively low. Additional efforts is needed to enable the pharmaceutical community to fully realize the benefits of these technologies.
... Pain from injections can be an impediment to patient adherence with therapy because microneedles are small; they do not hurt and therefore are better accepted by patients. In addition, fear of hypodermic needles is widespread and can be a barrier to patients' accessing health care (John et al., 2011) [15] . ...
... Pain from injections can be an impediment to patient adherence with therapy because microneedles are small; they do not hurt and therefore are better accepted by patients. In addition, fear of hypodermic needles is widespread and can be a barrier to patients' accessing health care (John et al., 2011) [15] . ...
Full-text available
Drug delivery is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals. It includes various approaches, formulations, technologies and systems for transporting a pharmaceutical compound in body as needed to safely achieve its desired therapeutic effect Microneedles are three-dimensional (3D) microstructures with micro-scale length (usually <1000 μm) that can pierce the stratum corneum and generate transient micro-channels through which external molecules can passively diffuse into the skin. Microneedles could be designed in a manner that the penetration depth is superficial enough to not touch nerve receptors in the lower reticular dermis, this result in a painless drug administration. It is promising that this microneedle-based transdermal delivery approach will offer a self-management, patient-friendly, and efficient administration route for drug delivery. This system has increased its application to many fields like oligonucleotides delivery, vaccine delivery, insulin delivery, and even in cosmetics.
... In doing so, the dose administered across the skin can be not only controlled but also reproducible. Through feedback questionnaires, users and healthcare professionals had expressed a preference towards an indicator device to confirm correct MAPs in-skin insertion [167]. Several concepts have been developed to address this request. ...
Full-text available
Since the first patent for micro array patches (MAPs) was filed in the 1970s, research on utilising MAPs as a drug delivery system has progressed significantly, evidenced by the transition from the simple 'poke and patch' of solid MAPs to the development of bio responsive systems such as hydrogel-forming and dissolving MAPs. In addition to the extensive research on MAPs for improving transdermal drug delivery, there is a growing interest in using these devices to manage infectious diseases. This is due to the minimally invasive nature of this drug delivery platform which enable patients to self-administer therapeutics without the aid of healthcare professionals. This review aims to provide a critical analysis on the potential utility of MAPs in managing infectious diseases which are still endemic at a global scale. The range of diseases covered in this review include tuberculosis, skin infections, malaria, methicillin-resistant Staphylococcus aureus infections and Covid-19. These diseases exert a considerable socioeconomic burden at a global scale with their impact magnified in low- and middle-income countries (LMICs). Due to the painless and minimally invasive nature of MAPs application, this technology also provides an efficient solution not only for the delivery of therapeutics but also for the administration of vaccine and prophylactic agents that could be used in preventing the spread and outbreak of emerging infections. Furthermore, the ability of MAPs to sample and collect dermal interstitial fluid that is rich in disease-related biomarkers could also open the avenue for MAPs to be utilised as a minimally invasive biosensor for the diagnosis of infectious diseases. The efficacy of MAPs along with the current limitations of such strategies to prevent and treat these infections will be discussed. Lastly, the clinical and translational hurdles associated with MAP technologies will also be critically discussed.
... 28 The participants in a study to determine the sentiments and thoughts of both the public and healthcare professionals regarding the use of MNAs in clinical practice thought self-administration of microneedle therapies could be advantageous in lessening visits to hospitals or clinics. 29 Patients can administer microneedles at point-of-care (POC) without the assistance of healthcare professionals and with minimal pain. 30 The capacity to release chemicals gradually for controlled drug delivery provided by MNAs encourages the prospective use of MNAs for long-term therapies. ...
Microneedle arrays are patches of needles at micro- and nano-scale, which are competent and versatile technologies that have been merged with microfluidic systems to construct more capable devices for biomedical applications, such as drug delivery, wound healing, biosensing, and sampling body fluids. In this paper, several designs and applications are reviewed. In addition, modeling approaches used in microneedle designs for fluid flow and mass transfer are discussed, and the challenges are highlighted.
... The widespread application and successful commercialization of microneedles depend on the acceptance of healthcare professionals and the general public's interest and confidence in the products [251,253]. Evidently, the general public and care givers prefer microneedles to conventional hypodermic needles, demonstrating that this novel technology has been favorably embraced [254,255]. An ideal microneedle system should enable proper self-administration, requiring no or minimal training or involvement with trained medical professionals. ...
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Transdermal delivery provides numerous benefits over conventional routes of administration. However, this strategy is generally limited to a few molecules with specific physicochemical properties (low molecular weight, high potency, and moderate lipophilicity) due to the barrier function of the stratum corneum layer. Researchers have developed several physical enhancement techniques to expand the applications of the transdermal field; among these, microneedle technology has recently emerged as a promising platform to deliver therapeutic agents of any size into and across the skin. Typically, hydrophilic biomolecules cannot penetrate the skin by passive diffusion. Microneedle insertion disrupts skin integrity and compromises its protective function, thus creating pathways (microchannels) for enhanced permeation of macromolecules. Microneedles not only improve stability but also enhance skin delivery of various biomolecules. Academic institutions and industrial companies have invested substantial resources in the development of microneedle systems for biopharmaceutical delivery. This review article summarizes the most recent research to provide a comprehensive discussion about microneedle-mediated delivery of macromolecules, covering various topics from the introduction of the skin, transdermal delivery, microneedles, and biopharmaceuticals (current status, conventional administration, and stability issues), to different microneedle types, clinical trials, safety and acceptability of microneedles, manufacturing and regulatory issues, and the future of microneedle technology.
... Since the discovery of MEMS, chemical and biological analyses, including molecular separation or environmental monitoring [25,26], as well as applications related to the pharmaceutical industry, have improved considerably [27]. MEMS used in biological applications is referred to as BioMEMS [28], and they are already being spun out into commercial applications using different types of devices such as micro-pumps [29], microrobots [30,31], biosensors [32], or microneedles [33]. There exists a considerable body of literature exploiting drug delivery micropumps using different types of actuation mechanisms such as piezoelectric [34][35][36], electrostatic [37], or electromagnetic [38] mechanisms. ...
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Given the demanding use of controlled drug delivery systems, our attention was focused on developing a magnetic film that can be triggered in the presence of a magnetic field for both drug delivery and the actuating mechanism in micropump biomedical microelectromechanical systems (BioMEMS). Magnetic alginate films were fabricated in three steps: the co-precipitation of iron salts in an alkaline environment to obtain magnetite nanoparticles (Fe3O4), the mixing of the obtained nanoparticles with a sodium alginate solution containing glycerol as a plasticizer and folic acid as an active substance, and finally the casting of the final solution in a Petri dish followed by cross-linking with calcium chloride solution. Magnetite nanoparticles were incorporated in the alginate matrix because of the well-established biocompatibility of both materials, a property that would make the film convenient for implantable BioMEMS devices. The obtained film was analyzed in terms of its magnetic, structural, and morphological properties. To demonstrate the hypothesis that the magnetic field can be used to trigger drug release from the films, we studied the release profile in an aqueous medium (pH = 8) using a NdFeB magnet as a triggering factor.
... Additionally, the recognition and acceptance of microneedles by pediatricians, children, and their parents are still controversial, as they may have some adverse consequences. Birchall et al. investigated the public and healthcare professionals' perceptions of microneedles, finding that the majority of respondents believed it was beneficial to children and that approximately 26% of healthcare professionals had a neutral attitude toward microneedles [113]. Because of their ability to overcome swallowing difficulties and painless mechanisms of oral medication, many children believe microneedles are appropriate for their age group [114]. ...
Fever in children is one of the most common symptoms of pediatric diseases and the most common complaint in pediatric clinics, especially in the emergency department. Diseases such as pneumonia, sepsis, and meningitis are leading causes of death in children, and the early manifestations of these diseases are accompanied by fever symptoms. Accurate diagnosis and real-time monitoring of the status of febrile children, rapid and effective identification of the cause, and treatment can have a positive impact on relieving their symptoms and improving their quality of life. In recent years, wearable diagnostic sensors have attracted special attention for their high flexibility, real-time monitoring, and sensitivity. Temperature sensors and heart rate sensors have provided new advances in detecting children's body temperature and heart rate. Furthermore, some novel formulations have also received wide attention for addressing bottlenecks in medication administration for febrile children, such as difficulty in swallowing and inaccurate dosing. In this context, the present review provides recent advances of novel wearable medical sensor devices for diagnosing fever. Moreover, the application progress of innovative dosage forms of classical antipyretic drugs for children is presented. Finally, challenges and prospects of wearable sensor-based diagnostics and novel agent-based treatment of fever in children are discussed in brief.
Microneedles (MNs) are microscopic needles that are applied to the skin in a minimally invasive way to facilitate transdermal drug delivery and/or uptake of interstitial fluid from the skin, which contains a variety of metabolites that can serve as biomarkers. The collection of interstitial fluid can be followed by post-sampling analysis or in situ real-time biosensing for disease diagnosis and drug monitoring. The painless and easy administration of MNs is appealing to patients, especially for long-term monitoring. In this Review, we discuss the use of MNs for biosensing purposes. We highlight the different types of MNs and sensing technologies used to develop MN-based biosensors. In addition, we discuss the potential to integrate MNs with wearable devices for real- time monitoring to improve point-of-care testing. Finally, we review the translational hurdles to be considered in bringing this technology from benchtop to bedside.
Microneedles have the clinical advantage of being able to deliver complex drugs across the skin in a convenient and comfortable manner yet haven't successfully transitioned to medical practice. Diabetes mellitus is a complicated disease, which is commonly treated with multiple daily insulin injections, contributing to poor treatment adherence. Firstly, this review determines the clinical prospect of microneedles, alongside considerations that ought to be addressed before microneedle technology can be translated from bench to bedside. Thereafter, we use diabetes as a case study to consider how microneedle-based-technology may be successfully harnessed. Here, publications referring to insulin microneedles were evaluated to understand whether insertion efficiency, angle of insertion, successful dose delivery, dose adjustability, material biocompatibility and therapeutic stability are being addressed in early stage research. Moreover, over 3,000 patents from 1970-2019 were reviewed with the search term '"microneedle" AND "insulin"' to understand the current status of the field. In conclusion, the reporting of early stage microneedle research demonstrated a lack of consistency relating to the translational factors addressed. Additionally, a more rational design, based on a patient-centred approach is required before microneedle-based delivery systems can be used to revolutionise the lives of people living with diabetes following regulatory approval.
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This book assembles a team of internationally-renowned researchers who share a commitment to rigorous, analytically-derived but non-polarized, qualitative research. The contributors reflect on the analysis of each of the kinds of data discussed in this book's observations, texts, talk and interviews—using particular examples of data-analysis to advance analytical arguments. Key themes discussed include: the centrality of the relationship between analytic perspectives and methodological issues; the need to broaden our conception of qualitative research beyond issues of subjective "meaning" and towards issues of language, representation and social organization; the desire to search for ways of building links between social science traditions and a commitment to a dialogue between social science and the community. Illuminating both the theory and the practice of qualitative analysis, this book will be a resource for all students involved in qualitative research. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
There is an increasing divergence of focus group practice between social researchers and commercial market researchers. This book addresses the key issues and practical requirements of the social researcher, namely: the kinds of social research issues for which focus groups are most and least suitable; optimum group size and composition; and the designing of focusing exercises, facilitation and appropriate analysis. The authors use examples, drawn from their own focus groups research experience, and provide exercises for further study. They address the three main components of composition, conduct and analysis in focus group research and also acknowledge the increasing impact the Internet has had on social research by covering the role and conduct of `virtual focus groups'.
To overcome the skin's barrier properties that block transdermal delivery of most drugs, arrays of microscopic needles have been microfabricated primarily out of silicon or metal. This study addresses microneedles made of biocompatible and biodegradable polymers, which are expected to improve safety and manufacturability. To make biodegradable polymer microneedles with sharp tips, micro-electromechanical masking and etching were adapted to produce beveled- and chisel-tip microneedles and a new fabrication method was developed to produce tapered-cone microneedles using an in situ lens-based lithographic approach. To replicate microfabricated master structures, PDMS micromolds were generated and a novel vacuum-based method was developed to fill the molds with polylactic acid, polyglycolic acid, and their co-polymers. Mechanical testing of the resulting needles measured the force at which needles broke during axial loading and found that this failure force increased with Young's modulus of the material and needle base diameter and decreased with needle length. Failure forces were generally much larger than the forces needed to insert microneedles into skin, indicating that biodegradable polymers can have satisfactory mechanical properties for microneedles. Finally, arrays of polymer microneedles were shown to increase permeability of human cadaver skin to a low-molecular weight tracer, calcein, and a macromolecular protein, bovine serum albumin, by up to three orders of magnitude. Altogether, these results indicate that biodegradable polymer microneedles can be fabricated with an appropriate geometry and sufficient strength to insert into skin, and thereby dramatically increase transdermal transport of molecules.
Calls for increased public participation in science and technology policy are now commonplace and raise challenges for social scientists as well as policy-makers. For social scientists, the practice of public participation raises questions about the methods used by social scientists to collect data and develop the representations of public opinion that inform this new dialogue but also reflect it. In this paper, the difference that different methods can make is illustrated by comparing the focus group data on perceptions of stem cell research with the more conventional survey based representations of public opinion. By examining how our data allow the uncertainty and ambivalence of participants to remain visible in its analysis, we argue that a more qualitatively informed social science can contribute to public debate in ways that go beyond the quantification of ‘pro’ and ‘anti’ positions that survey research appears to encourage. In particular, we argue that by providing, and in some sense sustaining, alternative representations of public concerns that resist polarization, social science can inform a more broad-ranging ‘upstream’ debate about the social purposes that science should serve. … there is nothing a government hates more than to be well-informed; for it makes the process of arriving at decisions much more complicated and difficult (John Maynard Keynes, quoted in Skidelsky, 1992, p. 630).