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Polymers in Drug Delivery Technology, Types of Polymers and Applications

  • Nirmala College of Pharmacy, Atmakur, India
DOI: 10.21276/sajp.2016.5.7.7
Scholars Academic Journal of Pharmacy (SAJP) ISSN 2320-4206 (Online)
Sch. Acad. J. Pharm., 2016; 5(7): 305-308 ISSN 2347-9531 (Print)
©Scholars Academic and Scientific Publisher
(An International Publisher for Academic and Scientific Resources)
Polymers in Drug Delivery Technology, Types of Polymers and Applications
V Sri Vajra Priya*, Hare Krishna Roy, N jyothi, N Lakshmi Prasanthi
Department of Pharmaceutics, Nirmala college of Pharmacy, Athmakur (V), Guntur, Andhra Pradesh, India
*Corresponding author
V. Sri Vajra Priya
Abstract: Polymers play a major role in the development of drug delivery technology by release of two types of drugs
like hydrophilic and hydrophobic. In a synchronized manner and constant release of formulations over extended periods.
There are numerous advantages of polymers acting as an inert carrier to which a drug can be conjugated, for example the
polymer improves the pharmacokinetic and pharmacodynamic properties of biopharmaceuticals through various ways,
like plasma ½ life, decreases the immunogenicity, build ups the stability of biopharmaceuticals, improves the solubility
of low molecular weight drugs, and has a potential of targeted drug delivery. However they have their own limitations,
such as the naturals polymers are most abundant and biodegradable but are difficult to reproduce and purify. Synthetic
polymers have high immunogenicity, which prevent their long term usage. Non-biodegradable polymers are needed to be
sugary after they release the drug at the targeted site. The general characteristic features that makes the polymer a
potential candidate for drug delivery include, safety, efficacy, hydrophilicity, absence immunogenicity biological
inactivity, sufficient pharmacokinetics, and presence of functional groups for covalent conjugation of drugs, targeting
moieties, or formation of copolymer.
Keywords: polymer, pharmacokinetics, controlled drug delivery, target-base drug deliver, co polymer, novel drug
Polymers are substances whose molecules have high
molar masses and compressed of a large number of
repeating units. Polymers can form particles of solid
dosage form and also can change the flow property of
liquid dosage form. Polymers are the backbone of
pharmaceutical drug delivery systems. Polymers have
been used as an important tool to control the drug
release rate from the formulation[2]. They are also
mostly used as stabilizer, taste-making agent, and
proactive agent. Modern advances in drug delivery are
now predicated upon the rational design of polymers
tailored specific cargo and engineered to exert distinct
biological functions.
Polymers are both naturally occurring and synthetic.
Among naturally occurring polymers are proteins,
starches, latex and cellulose. Synthetic polymers are
produced on a large scale and have a many properties
and used.
The polymers for the drug delivery system are
classified on the following characteristics:-
Origin- The polymers can be natural or synthetic,
or a combination of both.
Chemical nature- It can protein based, polyester,
cellulose derivatives, etc.
Backbone Stability- The polymers can be
degradable or non biodegradable.
Solubility- The polymer can hydrophilic or
hydrophobic in nature [5,9].
Polymers act as inert carriers to which a particular
drug can be conjugated. There are numerous advantages
of polymer acting as an inert carrier, for example, the
polymer enhances the pharmacodynamic and
pharmacokinetic properties of biopharmaceuticals
though several sources, such as, increases the plasma ½
life, decreases the immunogenicity, boost stability of
biopharmaceuticals, improves solubility of low
molecular weight drugs, and has potential for targeted
drug delivery[1]. Some drugs have a limited
concentration range by which utmost benefit can be
delivered. The concentrations above or below can cause
toxic effects or show no therapeutic effect. On the other
hand, the very slow progress in the efficacy of the
treatment of severe diseases, has suggested a growing
need for a multidisciplinary approach to deliver the
therapeutic to targets in the tissue. Through these new
innovations in pharmacodynamic, pharmacokinetic, non
specific toxicity, immunogenicity, biorecognition and
Review Article
Vajra Priya et al., Sch. Acad. J. Pharm., July 2016; 5(7):305-308
efficacy of the drug were generated. These new
strategies were often called as drug delivery systems
The polymers in the very starting stage they were
particularly used for non-biological uses, and were
selected because of their desirable physical properties,
for example:
Poly (methyl methacrylate) for physical strength
Poly (vinyl alcohol) for hydrophilicity and
Poly (urethanes) for elasticity.
Poly (ethylene) for toughness and lack of swelling.
Poly (siloxanes) or silicones for insulating ability.
Poly (vinyl pyrrolidone) for suspension
In order for controlled drug delivery formulation, the
polymers must be chemically inert and free from
impurities with appropriate physical structure, minimal
undesired aging, and to readily processable[7,22]. Few
Poly (ethylene-co-vinyl acetate)
Poly (methyl methacrylate)
Poly (vinyl alcohol)
Poly (N-vinyl pyrrolidone)
Poly (acrylic acid)
Poly (2hydroxy ethyl methacrylate)
Poly (methacrylic glycol)
Poly (ethelene glycol)
However in recent years the use of polymers were to
words medical applications and drug targeting few
examples are
Poly (lactide-co-glycolides) (PLGA)
Polyactide (PLA)
Polyglycolides (PGA)
Immediate drug release dosage form tablets:
Polymers including polyvinyl pyrrolidone and
hydroxypropylmethylecellulose (HPMC) are found to
be a good binder which increases the formation of
granules that improves the flow and compaction
properties of tablet formulations prior to tableting.
Many of the polymeric excipients used to “bulk out”
capsules fills are the same as those used in intermediate
release tablets. For hard and soft shell gelatin has most
often used[10]. By recent advances HPMC has been
accepted as alternative material for hard and soft
Modified drug release dosage forms:
To achieve gastro retention mucoadhesive and low
density, polymers have been evaluated, with little
success so far their ability to extend gastric residence
time by bonding to the mucus lining of the stomach and
floating on top of the gastric contents
Extended release dosage forms:
Extended and sustained release dosage forms prolong
the time that’ systemic drug levels are within the
therapeutic range and thus reduce the number of doses
the patient must take to maintain a therapeutic effect
there by increasing compliance[4,7]. The most
commonly used water insoluble polymers for extended
release applications are the ammonium ethacrylate
copolymers cellulose derivatives ethyl cellulose and
cellulose acetate, and polyvinyl derivative, polyvinyl
Gastro retentive Dosage forms:
Gastro retentive dosage forms offer an alternative
strategy for achieving extended release profile, in which
the formulation will remain in the stomach for
prolonged periods, releasing the drug insitu, which will
then dissolve in the liquid contents and slowly pass into
the small intestine.
Polymers used as colon targeted drug delivery:
Polymers plays a very important role in the colon
targeted drug delivery system. It protects the drug from
degradation or release in the stomach and small
intestine. It also ensures abrupt or controlled release of
the drug in the proximal colon[8].
Polymers in the mucoadhesive drug delivery system:
The new generation mucoadhesive polymers for
buccal drug delivery with advantages such as increase
in the residence time of the polymer, penetration
enhancement, site specific adhesion and enzymatic
inhibiton, site specific mucoadhesive polymers will
undoubtedly be uitilized for the buccal delivery of a
wide variety of therapeutic compounds. The class of
polymers has enormous for the delivery of therapeutic
Polymers for sustained release:
Polymers used in the sustain by preparing
biodegradable microspheres containing a new potent
osteogenic compound[16].
Polymers as floating drug delivery system:
Polymers are generally employed in floating drug
delivery systems so as to target the delivery of drug to a
specific region in the gastrointestinal tract i.e. stomach.
Natural polymers which have been explored for their
promising potential in stomach specific drug delivery
include chitosan, pectin, xanthan gum, guar gum, gellan
Vajra Priya et al., Sch. Acad. J. Pharm., July 2016; 5(7):305-308
gum, karkaya gum, psyllium, starch, husk, starch,
alginates etc[13].
Polymers in tissue engineering:
A wide range of natural origin polymers with special
focus on proteins and polysaccharides might be
potentially useful as carriers systems for active
biomoleculesor as cell carriers with application in the
tissue engineering field targeting several biological
Oraldrugdelivery system has been in practice since
many years as the most widely used root of
administration among all the roots that have been
employed for the systemic delivery of drug via various
pharmaceutical products for different dosage forms. A
large of both synthetic and natural has been studied for
possible application in drug delivery system[6].
The most advantageous property of polymers is that
they have been most widely used now a days. Two
promising synthetic polymers which have been
developed for biomedical applications are form
polyvinylpryolidone and polyethylene glycol acrylate
based hydrogels. Both of them are biodegradable and
forms copolymers with natural macromolecules.
On the other side, natural polymers have the
advantage of high biocompatibility and less
immunogenicity. A special attention has been shown
through the gelatin and collagen which are natural
polymers[20]. Other natural polymers include chitosan,
alginate, starch pectin, casein and cellulose derivatives.
The composites of some of the above natural polymers
with synthetic polymers give added advantages as
carriers for drugs delivery by complimenting the
properties of each other.
Hybrid copolymers of collagen with biodegradable
synthetic polymers polyethylene glycol 6000 and
polyvinylpyrolidone were developed for the controlled
released of contraceptive some drugs have an optimum
range within which maximum benefit is derived, and
concentrations above or below this range can be toxic
or produce no therapeutic belief it at all. On the other
hand, the very slow progress in the efficacy of the
treatment of severe disease, has suggested a growing
need for a multidisciplinary approach to the delivery of
therapeutics to targets in the tissues[19]. From this, new
idea on controlling the pharmacokinetic,
pharmacodynamics, non-specific toxicity,
immunogenicity, biorecognition, and efficacy of drugs
were generated. These new strategies, often called drug
delivery system (DDS), are based on interdisciplinary
approaches that combine pharmaceutics, polymer
science, analytical chemistry, and molecular
Polymers are used in the conventional dosage forms
like binders for enteric coted tablets which mask the
unpleasant taste, viscosity enhancers for controlling
flow in liquids[12], gel preparation in case of
semisolids and also used in preparation of transdermal
Future trust
Many researchers are working in this filed and have
developed many modify copolymers with desirable
functional groups, who visualize their use not only for
controlled drug delivery systems, but also used for
artificial organs lining, immunology testing, agents in
drug targeting, chemical reactors and substrates for cell
growth[17]. The most potential opportunities for these
polymers in controlled drug delivery lie in the field of
responsive delivery systems, it is expected that, in
future even more than today, researches and doctors
will have a wealth of products using biodegradable
polymers that will help faster patient recovery and
eliminate follow up surgeries[3]. Looking to present
scenario and a wide range of research, total use of these
biodegradable polymers in drug delivery applications is
within reach in the near future.
The use if novel polymers not only offers benefits but
also can to be harmful because of the toxicity and other
incompatibilities associate with them. Polymers
possessing a unique strength in their application
towards drug delivery application which enables the
new advancement in the formulating new drug delivery
systems which improves the therapy and treatment .
Care should be taken to properly select polymers while
designing a delivery system. The ultimate goal is to
introduce cost effective ,biocompatible, multifunctional.
less toxic polymers so that the delivery systems pass
through the various phases of clinical trials and benefit
the society . Among various types of polymer hydrogels
polymer blends of natural and or synthetic polymer are
used in the pharmaceutical formulations .In that
controlled drug delivery systems having a advantages
over conventional therapy fall into various categories
such as diffusion controlled chemically controlled,
solvent activated and modulated release systems. On the
whole, polymers are being extensively used in
pharmaceutical industry due to their vast applications.
1. Duncan R ; The dawning era of polymer
therapeutics. Nature Reviews Drug Discovery,
2003; 2:347360.
2. Raizada A, Bandari A, Kumar B;Polymers in
drug delivery : A Review. International
Journal of pharma research and development,
2010; 2(8):9-20.
3. Poddar RK, Rakha P, Singh SK, Mishra DN.
Bioadhesive Polymers as a Platform for Drug
Delivery: Possibilities and Future Trends.
Vajra Priya et al., Sch. Acad. J. Pharm., July 2016; 5(7):305-308
Research Journal on Phamaceutical Dosage
Form and Technology, 2010; 2(1): 40-54.
4. Charman WN, Chan HK, Finnin BC, Charman
SA; Drug Delivery: A Key Factor in Realising
the Full Therapeutic Potential of Drug. Drug
Development Research 1999; 46:316-27.
5. Chandel P, Rajkumari, Kapoor A, Polymers
A Boon To Controlled Drug Delivery System,
International research journal of pharmacy
(IRJP), 2013; 4(4), 28 34.
6. Kim S, Kim JH, Jeon O, Chan I, Park KK;
Engineered Polymers for Advanced Drug
Delivery. European Journalof Pharmaceutics
and Biopharmaceutics. 2009; 71(3): 420-430.
7. Harekrishna Roy, Sanjay Kumar Panda, Kirti
Ranjan Parida , Asim Kumar Biswal.
Formulation and In-vitro Evaluation of Matrix
Controlled Lamivudine Tablets. International
Journal of Pharma Research and Health
Sciences 2013; 1(1): 1-7.
8. Nair Lakshmi S., Laurencin Cato T. Polymers
as Biomaterials for Tissue Engineering and
Controlled Drug Delivery. Tissue Engineering
I Publisher: Springer Berlin / Heidelberg,
2006; 203- 210.
9. Bernardo Cordovez, Aram J. Chung, Michael
Mak, David Erickson, A novel polymer
microneedle fabrication process for active
fluidic delivery. 2011;10:785791.
10. Heller J. Biodegradable polymers in controlled
drug delivery. Critical Reviews™ in
Therapeutic Drug Carrier Systems, 1984; 1(1):
11. RaoPanduranga; New concepts in controlled
drug delivery.PURE and applied chemistry
1998; 70(6): 1283-1287.
12. Harekrishna Roy, Anup K Chakraborty,
Bhabani Shankar Nayak, Satyabrata Bhanja,
Sruti Ranjan Mishra, P. Ellaiah. Design and in
vitro evaluation of sustained release matrix
tablets of complexed Nicardipine
Hydrochloride. International Journal of
Pharmacy and Pharmaceutical Sciences, 2010;
14. Jones David. Pharmaceutical Applications of
Polymers for Drug Delivery. ChemTec
Publishing Inc., 2004; 300-301.
15. Malafaya PB, Silva GA, Reis RL; Natural
origin polymers as carriers and scaffolds for
biomolecules and cell delivery in tissue
engineering applications. Advanced Drug
Delivery Reviews, 2007; 59: 207-233.
16. Sanghi DK, Borkar DS, Rakesh T; The Use of
Novel Polymers In A Drug Delivery & Its
Pharmaceutical Application. Asian Journal of
Biochemical and Pharmaceutical Research
2013; 2(3): 169-178.
17. Harekrishna Roy; Formulation of Sustained
Release Matrix Tablets of Metformin
hydrochloride by Polyacrylate Polymer. Int J
Pharma Res Health Sci. 2015; 3(6): 900-906.
18. Harekrishna Roy, P. Venkateswar Rao, Sanjay
Kumar Panda, Asim Kumar Biswal, Kirti
Ranjan Parida, Jharana Dash. Composite
alginate hydrogel microparticulate delivery
system of zidovudine hydrochloride based on
counter ion induced aggregation. Int J Applied
Basic Med Res. 2014; 4(Sup 1): S31-36.
19. Muller-Goymann CC; Physicochemical
characterization of colloidal drug delivery
systems such as reverse micelles, vesicles,
liquid crystals and nanoparticles for topical
administration. European Journal of
Pharmaceutics and Biopharmaceutics 2004;
20. Satyabrata Bhanja, Sudhakar M, Neelima V,
Panigrahi BB, Harekrishna Roy. Development
and Evaluation of Mucoadhesive Microspheres
of Irbesartan. International Journal of Pharma
Research and Health Sciences, 2013; 1(1): 8-
21. CG. Wilson, G. Mukherji, HK. Sha. Modified-
release Drug Delivery Technology:
Biopolymers and Colonic Delivery. 2nd
edition. Informa Healthcare, New York 2008:
22. Poddar RK, Rakha P, Singh SK, Mishra DN.
Bioadhesive Polymers as a Platform for Drug
Delivery: Possibilities and Future Trends.
Research J on Phamacetical Dosage Form and
Technology 2010; 2(1): 40-54.
23. Satturwar PM, Fulzele SV, Dorle AK;
Biodegradation and in vivo biocompatibility of
rosin: a natural filmforming polymer.
American assosication of Pharmaceutical
scientists, 2003;4: 1-6.
24. Pua X, Liub J, Guoc Y, Yana X, Yanga H,
Yuana Q. Study progression in polymeric
micelles for the targeting delivery of poorly
soluble anticancer agents to tumor, Asian
Journal of Pharmaceutical Sciences, 2012;7
(1): 1-17.
25. Duncan R; The dawning era of polymer
therapeutics. Nature Reviews Drug Discovery,
2003; 2:347360.
26. Charman WN, Chan HK, Finnin BC, Charman
SA; Drug Delivery: A Key Factor in Realising
the Full Therapeutic Potential of Drugs. Drug
Development Research, 1999; 46:316-27.
27. Kopecek J; Smart and genetically engineered
biomaterials and drug delivery systems.
European Journal of Pharmaceutical Sciences
2003; 20:1-16.
... In general, such system possess a linear or a branched polymer chain, that can function like a bioactive molecule or as the inert carrier covalently linking the drug, e.g., dendrimers, polymer-drug conjugates, polymer-antibody conjugates, polymeric micelles, polymer-DNA conjugate, nanocapsule, multicomponent polyplexes and nanosphere [45]. The key broad characteristics based on which the polymers for drug delivery can be classified [56] are provided in Table 2. Natural polymers, as they are abundant and biodegradable (e.g., chitosan based or cellulose based) have also been extensive explored for biomedical applications. However, one of the challenges observed includes that the natural polymers are difficult to reproduce and purify. ...
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Recent years have visualized the entry of various new life-threatening diseases in the form of epidemic and pandemic and hence the introduction of novel drug delivery systems is highly vital for saving the lives of people. Recent research in this area portrays a relentless search for overcoming the disadvantages of older systems and replacing them with novel systems. Polymer based drug delivery systems and nanoparticles-based systems are two such developing areas that are discussed in this review. Recent studies have also shown a surge in the application of polymer lipid hybrid nanoparticles in drug delivery systems and also bioorthogonal catalytic reactions for the release of drugs at target site by unmasking reaction of prodrugs. This review highlights the various developments and innovations in the drug delivery field in the recent years with respect to these systems and throws light on the advances in the treatment of diseases in different areas accomplished by means of these systems. Graphical Abstract
... Additionally, synthetic polymers possess more reproducible physical and chemical properties compared to natural polymers [107]. However, due to their association with high immunogenicity [107], synthetic polymers are commonly used for short-term applications [108]. A summary of some of the synthetic polymers used in gel development are provided in Figure 4 ...
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Gels are attractive candidates for drug delivery because they are easily producible while offering sustained and/or controlled drug release through various mechanisms by releasing the therapeutic agent at the site of action or absorption. Gels can be classified based on various characteristics including the nature of solvents used during preparation and the method of cross-linking. The development of novel gel systems for local or systemic drug delivery in a sustained, controlled, and targetable manner has been at the epitome of recent advances in drug delivery systems. Cross-linked gels can be modified by altering their polymer composition and content for pharmaceutical and biomedical applications. These modifications have resulted in the development of stimuli-responsive and functionalized dosage forms that offer many advantages for effective dosing of drugs for Central Nervous System (CNS) conditions. In this review, the literature concerning recent advances in cross-linked gels for drug delivery to the CNS are explored. Injectable and non-injectable formulations intended for the treatment of diseases of the CNS together with the impact of recent advances in cross-linked gels on studies involving CNS drug delivery are discussed.
... Polymers act as an inert carrier to which a drug can be conjugated. They show constant release of formulation over a longer period, improve the pharmacokinetic and pharmacodynamic property, and decrease immunogenicity [3,4]. Polymers are used in a myriad of pharmaceutical applications, including viscosity and flow controlling agents in liquids, binders in tablets, drug release modifiers, solubility enhancers, etc. [5]. ...
The limitations of non-biodegradable polymers have paved the way for biodegradable polymers in the pharmaceutical and biomedical sciences over the years. Poly (lactic-co-glycolic acid) (PLGA), also known as ‘Smart polymer’, is one of the most successfully developed biodegradable polymers due to its favorable properties, such as biodegradability, biocompatibility, controllable drug release profile, and ability to alter surface with targeting agents for diagnosis and treatment. The release behavior of drugs from PLGA delivery devices is influenced by the physicochemical properties of PLGA. In this review, the current state of the art of PLGA, its synthesis, physicochemical properties, and degradation are discussed to enunciate the boundaries of future research in terms of its applicability with the optimized design in today’s modern age. The fundamental objective of this review is to highlight the significance of PLGA as a polymer in the field of cancer, cardiovascular diseases, neurological disorders, dentistry, orthopedics, vaccine therapy, theranostics and lastly emerging epidemic diseases like COVID-19. Furthermore, the coverage of recent PLGA-based drug delivery systems including nanosystems, microsystems, scaffolds, hydrogels, etc. has been summarized. Overall, this review aims to disseminate the PLGA-driven revolution of the drug delivery arena in the pharmaceutical and biomedical industry and bridge the lacunae between material research, preclinical experimentation, and clinical reality.
The last chapter of this book provides basic information on regenerative strategies that use scaffolds and their biotechnological applications. After providing possible definitions for regenerative medicine and tissue engineering, the necessary steps for tissue regeneration by use of scaffolds are illustrated, followed by a description of biodegradable materials and the methods used for scaffold fabrication. A description of cell types and dynamic cell culture devices (bioreactors) close the first part of this chapter. The last part of this chapter covers the basics of biotechnology and its main branches, addressing specific recombinant DNA technologies, such as the generation of genetically modified organisms, gene and organism cloning, and gene therapy at both the theoretical and application levels. It then moves on to the theoretical and practical use of the polymerase chain reaction.
Captopril is an angiotensin-converting enzyme (ACE) inhibitor that prevents angiotensin I (ATI) from being converted to angiotensin II (ATII). However, it offers certain limitations like instability, dose dumping and burst release due to its usage in the native state. In the last two decades, different polymers and excipients have been used to make captopril more accessible and well-accepted. The present work discusses the efforts made by various scientists so far to make the oral administration of captopril more acceptable by overcoming its limitations. The different factors affecting gastric retention, approaches to achieve better gastric retention. The oral managed release dosage forms have enormous curative benefits such as improved therapeutics and better patient compliance. The polymer based gastro-retentive drug delivery systems (GRDDS) include microspheres, soild inclusion complex, floating tablets, alginate based beads, etc utilizes better retention in the stomach for longer duration of action and improved bioavailability. Overall, the work aims to summarize the attempts made as novel drug delivery approaches over the last two decades in reverse chronological order to make captopril more gastro retentive and orally acceptable by the patients.
Atenolol‐polyacrylate and intercalated atenolol‐polyacrylate onto montmorillonite clay was synthesized as drug delivery systems. The synthesis was carried out by free radical homo and copolymerization of acrylate drug (atenolol) monomer with different co‐monomers. The intercalation of polymeric drug systems onto montmorillonite clay was achieved through ion exchange process. The characterization of the prepared systems was investigated by different analytical techniques. The release studies of drug (atenolol) were studied over a long time in aqueous mediums at conditions nearly present in human body. Synthesis, characterization and release study for polymeric drug and intercalated polymeric drug.
Design and development of engineered nanomaterials is a highly fascinating area of research that has intersected almost every sector of science and technology in the modern era. Especially in biomedical research, engineered nanomaterials are a highly promising candidate and are finding applications as nanomedicines and nanodelivery systems. These, nanoscale materials have also been used as diagnostic tools and as drug delivery system to transport pharmaceutical drugs to specific target sites in a controlled and sustained manner. Pharmaceutical drugs have numerous drawbacks, such as poor bioavailability, low solubility, and high dose requirement due to the first-pass metabolism. Therefore, nanomaterials are being investigated as potential drug delivery vehicles for transporting the pharmaceutical drug to the target site. These nanomaterials are ideal candidates for site-specific delivery due to their unique properties such as small size, high surface-area-to-volume ratio, ability to undergo surface functionalization to achieve targeted delivery, enhanced circulation time inside the body, ability to escape reticuloendothelial system, ability to reduce therapeutic indices and overcome solubility and permeability issues of drugs (such as curcumin) by encapsulating them. Nanomaterials are also being used in chemotherapy and immunotherapy to treat the gravest of human diseases such as cancer and autoimmune disorders. These wide ranges of applications emphasize the importance of studying their physicochemical properties in greater detail. Therefore, this chapter highlights and discusses the recent research in this area and provides a comprehensive summary of the ongoing research towards the development and application of engineered nanomaterials in drug delivery for developing innovative therapies and biomedicines.
Controlled release of active ingredients using polymer microcapsules is a promising approach for many consumer products, personal care products, agrochemical formulations, paints, and coatings. An ideal encapsulation matrix for such applications should be non-toxic in nature, provide a robust mechanical wall and yet allow controlled diffusion, have good adhesion to the applied substrate and be cost effective. This book chapter provides a brief overview of different microencapsulation methods for polymer based microcapsules, its properties and applications
Introduction: Eggshell membrane (ESM) is a tissue found between the eggshell and the albumen of eggs that has attractive properties for use in drug delivery systems. Aim: To incorporate in ESM and used it as a model drug in release studies. The color change and FTIR analysis of the biopolymer proved the incorporation of nimesulide in ESM. Results: The drug uptake was 176.83 and 122.69 mg g⁻¹ by natural and cross-linked ESM. Release studies were carried out using a spectrophotometric flow system in simulated intestinal fluid pH 7.4. The release profiles showed that after 60 minutes 54.55 and 42.58 % of the drug were released from natural and cross-linked ESM, respectively. Kinetics parameters indicated that drug release was better described by the Higuchi model and through a non-Fickian release. Conclusion: Considering these results is proved that ESM has the potential to become a polymeric matrix for drug release systems.
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Polymer plays a vital role in novel drug delivery systems with its longevity and self-transforming quality as excipient in tablet and capsule formulations. Use of polymer is now extended to controlled-release and drug-targeting systems. Polymers are obtained from natural sources as well as chemically synthesised. Polymers obtained from natural resources are used as such and also chemically modified for various applications. Polymers are classified as biodegradable and non biodegradable. The majority of biodegradable polymers used in controlled drug delivery undergo bulk erosion. In the present paper, classification of polymer along with their characteristics is given.
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The objective of present work is to develop and characterize an oral sustained release matrix tablet of complexed Nicardipine Hydrochloride by employing hydrophilic and hydrophilic polymers. Due to poor water solubility of the drug its bioavailability is dissolution rate limited. The purpose of the study was to increase the solubility of Nicardipine by cyclodextrin inclusion complex technique. Complexes of different molar ratio were prepared. Kneading method was employed for preparation of inclusion complexes. Among different complexes, a complex with 1:1 molar ratio of drug and β-CD showed the highest dissolution rate. Matrix tablets were prepared by direct compression technique using different concentration of polymers and selected complex. The blended powders and tablets were evaluated for various physico-chemical parameters as per official protocol. The invitro dissolution study was carried out in acidic medium (pH 1.2) for 2 hrs, followed by phosphate buffer dissolution medium (pH 6.8) for next 12 hrs. The blended powders showed satisfactory flow properties and compressibility. All the tablet formulations showed acceptable pharmacotechnical properties and complied with official specifications. The invitro release pattern indicated that formulation F7 was good releasing the drug for period of 12 hrs and was best fitted to Higuchi release profile. The present study has demonstrated that combination of hydrophobic and hydrophilic polymers effectively sustained the drug release for prolonged period of time and a minimum of 28 % sodium alginate is required to retard the release of nicardipine from matrix tablet for the period of 12 hours.
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Polymeric micelles (PMs) have emerged as versatile drug carriers during the past decades. PMs formed from an amphiphilic block copolymer are suitable for encapsulation of poorly water-soluble, hydrophobic anticancer drugs. Importantly, critical features of the PMs as drug carriers, including particle size, stability, loading capacity and release kinetics of drugs allow PMs to be targeted to the tumor site by a passive mechanism called the enhanced permeability and retention effect. Also, nano-engineering of block copolymers might allow the preparation of PMs with certain external triggers such as specific-tissue targetability by conjugating with many ligands including polymeric immunomicelles, the folate receptor, transferrin, epidermal growth factor (EGF), and α2-glycoprotein antibody fragments, epidermal growth, as well as with physical stimuli-sensitivity,such as the use of pH-sensitivity, thermosensitivity, ultrasound, and dendritic photosensitizer. Therefore, PMs can be targeted to tumor sites by passive as well as active mechanisms. A variety of mechanisms have recently been described to accomplish this transition, which will be reviewed in this paper. This review summarizes recently available information regarding targeting of anticancer drugs to the tumor site using PMs.
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Aim: The present study deals with preparation of zidovudine loaded microparticle by counter ion induced aggregation method. During this study effect of polyacrylates and hypromellose polymers on release study were investigated. Materials and Methods: The ion induced aggregated alginate based microparticles were characterized for surface morphology, particle size analysis, drug entrapment study, in-vitro study, Fourier-transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC) study. Results and Discussion: The result showed Eudragit RL-100 (ERL) based formulations had smoother surface as well as their mean particle sizes were found greater compared with Eudragit RS-100 (ERS) microparticles. Furthermore, drug entrapments were found to be more in ERL formulae as compared with ERS. RL3 released 101.05% drug over a period of 8th h and followed Higuchi profile and Fickian diffusion. Moreover, data obtained illustrated that, higher amount of quaternary ammonium group, alkali value, and glass transition temperature may be possible reason for improving permeability of ERL based formulations. It was also noticed, hyroxypropyl methylcellulose (HPMC) K4M premium grade polymer sustained drug release more than HPMC K15M. In addition, drug-excipient interaction study was carried out by FTIR and DSC study.
The design, synthesis, and properties of novel stimuli-sensitive and genetically engineered biomaterials and drug delivery systems are reviewed. Two approaches to their engineering are presented. One approach is to improve the traditional methods of synthesis, as demonstrated by the example of controlled copolymerization of α-amino acid N-carboxyanhydrides. The other approach, discussed in more detail, uses genetic engineering methods. The design of hybrid hydrogel systems whose components derive from at least two distinct classes of molecules, e.g., synthetic macromolecules and protein domains, is assessed. The design of self-assembling block copolymers is discussed in detail. Finally, the pharmaceutics related applications of these materials are presented.
Drug delivery is a key factor contributing to the commercial and therapeutic potential of many drugs and related products. Drug delivery underpins the development of new chemical entities, and it is the driving force behind the development of many new devices and formulation-based projects. There are many exciting drug delivery projects being undertaken in commercial organisations, universities and research institutes throughout Australia. This article describes projects in the field of lipids and oral drug delivery, protein formulation and stability, aerosol drug delivery and transdermal drug delivery which are being undertaken in the authors' laboratories. It is hoped that these projects provide some insight into the scope and breadth of drug delivery research being conducted in “The Antipodes.” Drug Dev. Res. 46:316–327, 1999.