Physical and chemical properties of deionized water and saline treated with low-pressure and low-temperature plasma

Abstract

Low temperature plasma, also known as cold plasma, has been used in many industries, including the synthesis of biomaterials, in order to improve the clinical efficacy of medical implants by a diverse modification of their surface. The cold plasma process is characterized by a low degree of ionization at a low atmospheric
pressure. In order to produce low-temperature plasma at first a compound is converted into a state of ionized gas and through the use of thermal energy in the form of direct or alternating current, radiation or laser. The potential applications of low temperature plasma are due to the change of surface properties, including the electrochemical reduction and the nature of the chemical groups. Therefore, properties such as hardness, physical abrasion, corrosion, and the water absorption capacity and affinity to specific molecules are possible to be modified using cold plasma. As a result of the substance undergoing low-temperature low-pressure plasma resonance, a substantial change occurs in its physicochemical properties, yet the effects of the application of cold plasma reactor for basic physicochemical properties of liquids such as water and physiological saline are unknown.
In this study, samples of physicochemical deionized water and saline were evaluated. The tests were carried out 7 days after deionization and / or operation of the low-temperature low-pressure plasma resonance in deionized water. An analysis was performed for the properties of water such as pH, conductivity, surface tension, density and dynamic viscosity. All measurements were performed at 24° C. Each measurement was repeated 6 times
for a sample for all tested sizes.

Full text

science • technique
722 • nr 8/2013 • tom 67
Physical and chemical properties of deionized
water and saline treated with low-pressure
and low-temperature plasma
Joanna MYSTKOWSKA, Jan R. DĄBROWSKI – Department of Materials and Biomedical Sciences,
Bialystok Technical University, Bialystok, Krzysztof KOWAL, Department of Allergology and Internal
Medicine, Medical University of Bialystok, Katarzyna NIEMIROWICZ, Halina CAR – Department of
Experimental Pharmacology, Medical University of Bialystok
Please cite as: CHEMIK 2013, 67, 8,
Introduction
Low temperature plasma, also known as cold plasma, has been
used in many industries [1], including the synthesis of biomaterials, in
order to improve the clinical efcacy of medical implants by a diverse
modication of their surface [2]. The cold plasma process is
characterized by a low degree of ionization at a low atmospheric
pressure [2, 3]. In order to produce low-temperature plasma at rst
a compound is converted into a state of ionized gas and through the
use of thermal energy in the form of direct or alternating current,
radiation or laser [1, 3]. The potential applications of low temperature
plasma are due to the change of surface properties, including the
electrochemical reduction and the nature of the chemical groups.
Therefore, properties such as hardness, physical abrasion, corrosion,
and the water absorption capacity and afnity to specic molecules
are possible to be modied using cold plasma [4÷6]. As a result of
the substance undergoing low-temperature low-pressure plasma
resonance, a substantial change occurs in its physicochemical
properties, yet the effects of the application of cold plasma reactor
for basic physicochemical properties of liquids such as water and
physiological saline are unknown.
In this study, samples of physicochemical deionized water and
saline were evaluated. The tests were carried out 7 days after
deionization and / or operation of the low-temperature low-
pressure plasma resonance in deionized water. An analysis was
performed for the properties of water such as pH, conductivity,
surface tension, density and dynamic viscosity. All measurements
were performed at 24° C. Each measurement was repeated 6 times
for a sample for all tested sizes.
The experimental part
Material
Deionized water and saline (Fresenius Kabi Poland Sp.) have been
subjected to low-temperature plasma. 0.9% NaCl solution with a volume
of 0.5 litre standard production of Fresenius Kabi Poland Ltd, and water
deionized by reverse osmosis were supplied in containers of 0.2 litre.
Methods At the NANTES Nanotechnology Systems Ltd
laboratories, deionized water and physiological saline were subjected
to low-pressure low-temperature plasma with the use of a reactor at
the following parameters: temperature of plasma 38° C, 5x10‒3 mbar
vacuum, 600 V voltage, 50 mA intensity and frequency of 280 GHz
[7, 8], in the environment of residual gases, without the ow of other
gases, without any change of parameters in the process. The material
was placed in sealed containers with a capacity of 0.5 litre (saline) or
0.2 litre (deionized water), subject to no rotation. The impact of the
plasma on the object was of a pulsatile nature with the synchronization
network for 40 minutes.
The pH and conductivity tests were carried out by means of suitable
measuring electrodes cooperating with the multifunctional SevenMulti
ionic conductivity meter from Mettler Toledo. The pH ratings were
made using Clarytrode 120 electrode. The conductivity measurements
were made using the InLab740 conductivity cell from Mettler Toledo
with an integrated probe for measuring the temperature of the tested
solution. The surface tension tests were performed using the STA1
tensiometer from Sinterface. For density tests, a pycnometer by Gay-
Lusaka was used. The rheological measurements (measurement of
the dynamic viscosity as a function of shear rate) was carried out using
a RheoStress6000 rheometer from Haake, and a Thermo Scientic cone
measuring system (C35/2o TIL) – plate (MP35) of outer solvent-trap.
The study of physicochemical properties of samples treated
with low temperature plasma:
For all physiochemical measurements we used 3 specimens of water
and 0.9% NaCl not treated with plasma process, and deionized water
and saline, which underwent a low-temperature low-pressure plasma
resonance (Tab.1). The results were analyzed statistically using the
student’s t-test with the PQStat software. The results were presented
as arithmetic means with the indication of the standard deviation (SD).
The results were considered statistically signicant at p <0.05. In order
to determine the level of signicance, the following indications were
used: p <0.05 * p <0.01 ** p <0.001 *** in order to compare the
same type of liquid treated with and not treated with plasma.
Table 1
Summary of tested substances
Symbol Substances
A
Deionized water
B
Deionized water
+ plasma
C 0,9% NaCl
D0,9% NaCl + plasma
The results and discussion
The results of the measurements of selected physicochemical
properties of deionized water and 0.9% NaCl showed differences
between the two samples. The pH of deionized water evaluated after
7 days from the deionization was about 5.4. There was a signicantly
higher and statistically relevant pH value (7.85) for the deionized water
after plasma process (Fig. 1). The pH (5.9) of 0.9% NaCl was slightly
lower than the 0.9% NaCl treated with plasma (pH 5. 99) – however,
this difference reached a statistical signicance (Fig. 1). There was
a signicant difference in : the conductivity of deionized water was
13.53 mS/ cm-1, while of deionized water treated with plasma was
403 mS /cm-1 (p <0.001) (Fig. 2A). The conductivity of 0.9% NaCl
(d=12.37 mS/cm-1 ) was lower than that of saline treated with plasma
(d=13.47 mS/cm-1) (Fig. 2B). In the study [9] we investigated the
conductivity of deionized water treated with a variety of factors.
Differences were obtained in the test volume, depending on the

science • technique
nr 8/2013 • tom 67 • 723
applied medium. The electrolytic conductivity depends on the amount
of the free ions in water and their ability to move. The analyzed
deionized water treated with plasma had a signicantly higher surface
tension (g=45 mN×m-1) in reference to the untreated deionized
water (g=34 mN×m-1), while physiological saline treated with
plasma was characterized by statistically signicantly lower surface
tension (g=31 mN×m-1) than 0.9% NaCl not treated with plasma
(g=44 mN×m-1). (For comparison, the surface tension of freshly
distilled water according to×the papers [10÷12] is respectively 72.44
and 72.49 mN× m-1. Density and viscosity of the two tested uids have
not changed signicantly under the inuence of plasma (Figs. 4, 5).
Fig. 1. pH values of tested substances
Fig. 2A. Conductivity of deionized water
Fig. 2B. Conductivity of 0,9% NaCl
Fig. 3. Surface tension of tested substances
Fig. 4. Density of tested substances
Fig. 5. Viscosity of tested substances
Summary and conclusions
The physicochemical studies have clearly shown that the
deionized water and saline subjected to low-temperature low-
pressure plasma signicantly changed their properties such as pH,
electrical conductivity and surface tension as compared to their
counterparts not treated with plasma. The procedure of processing
deionized water using a low-pressure and low-temperature plasmas
have been submitted to patent admission [7].

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724 • nr 8/2013 • tom 67
Literature
1. Chen F.F. Industrial applications of low temperature plasma physics.
Materiały konferencyjne. 1994, 1–24.
2. Schlosser M., Walschus U., Schroder K., Finke B., Nebe B., Meichsner
J., Hippler R., Bader R., Podbielski A. Application of Low-Temperature
Plasma Processes for Biomaterials, Biomaterials Applications
for Nanomedicine, Prof. Rosario Pignatello (Ed.), InTech. 2011,
127–142.
3. Hippler R., Kersten H., Schmidt M., Schoenbach K.H. Low temperature
plasma physics: Fundamental aspects and applications. Wiley-VCH,
Weinheim, Germany. 2008, 15–29.
4. Kobel P., Mączka T. Zastosowanie plazmy niskotemperaturowej
w technice spalania Archiwum Spalania. 2009, 9: 161–180.
5. Meichsner J., Schmidt M., Wagner H.E. Non-thermal Plasma Chemistry
and Physics.Taylor & Francis, London, UK. 2011, 5–117.
6. Bonizzoni G., Vassallo E. Plasma physics and technology; industrial
applications, Vacuum. 2002, 64: 327–336.
7. Patent application. Nr P.389626
8. http://www.nantes.pl/
9. Boluanger L. Observations on variation in electrical conductivity of pure
demineralized water: modification („activation”) of conductivity by low
frequency, low-level alternativing electric fields. Int. J. Biometeorol.
1998, 4: 137–140.
10. Cheng W., Chen Z., Akisawa A., Hu P., Kashiwagi T. Theoretical and
experimental study on surface tension and dynamic surface tension of
aqueous lithium bromide and water with additive. Science in China.
2003, 46(2): 192–203.
11. Kim K.J., Berman N.S. Surface tension of aqueous lithium bromide+2-
ethyl-1-hexanol. J Chem Eng Data. 1994, 39: 122–124.
12. Kulankara S. Effect of enhacement additives on the absorption of
water vapor by aquesous lithium bromide, Ph.D Dissertation, 1999,
University of Maryland, USA.
Acknowledgement
This study was performed under the project “Studying, researching,
commercializing – of the doctoral support program at UMB”, Measure 8.2.1
of the Human Capital Operational Programme, co-nanced by the European
Union under the European Social Fund Programme. Special thanks are
directed by the authors to the company of NANTES Nanotechnology Systems
in Boleslawiec for conducting the plasma processes and providing uids for
evaluation as well as covering the editorial costs.
Translation into English by the Author
Joanna MYSTKOWSKA – Ph.D., is a graduate of the Faculty of
Chemistry, Warsaw University of Technology (2003). Doctoral thesis
defended at the Faculty of Materials Science and Engineering, Warsaw
University of Technology. She currently works in the Department
of Materials and Biomedical Sciences Bialystok Technical University.
Scientic interest: biopolymers, biological uids and biolm. She is
an author of several chapters in international scientic monographs,
29 articles in scientic-technical journals and author or co-author
of 24 papers and communications presented at national and
international conferences.
e-mail:j.mystkowska@pb.edu.pl; phone +85 746 92 51
Krzysztof KOWAL – Ph.D., is a graduate of the Faculty of Medicine
(1990), Medical University of Bialystok. He completed his Ph.D. degree
in 1991 at the Faculty of Medicine of the Medical University of Bialystok.
During the four years received two specializations of internal diseases and
allergy. In 2009, he defended his habilitation thesis in medical science. He
currently works as an assistant professor in the Department of Allergology
and Internal Medicine, Medical University of Bialystok. He has authored or
co-authored more than 70 publications and 100 communications. He is also
an author of six chapters in textbooks. His interests focus on the mechanisms
of the inammatory response, the impact of exogenous substances on the
cellular response and the implementation of new therapeutic approaches
including targeted therapy.
e-mail:kowalkmd@umb.edu.pl; phone:+85 746 83 73
Katarzyna NEMIROWICZ – M.Sc., is a graduate (chemistry) of the Faculty
of Biology and Chemistry, University of Bialystok (2011) and Laboratory
Medicine at the Medical University of Bialystok (2012). At present she is the
second year PhD student in the Department of Experimental Pharmacology,
Medical University of Bialystok, Faculty of Medicine. Since February 2013
she has been a principal investigator the grant Prelude. She is also the
beneciary of a program “I study, investigate, commercialize” – UMB doctoral
support program funded by the European Union under the European Social
Fund as well as the scholar of Polpharma Science Foundation Scholarship.
Research interests: organic synthesis, nanotechnology and targeted therapy.
She is the author and co-author of ve research papers, 13 papers and
communications runs at national and international conferences, as well as
a patent application.
e-mail: katarzyna.niemirowicz@umb.edu.pl; phone: +85 748 55 54
Halina CAR – M.D., Ph.D., is a graduate of the Faculty of Medicine, Medical
University of Bialystok (1987). She obtained the degree of Doctor of Medicine
in 1990, and defended her habilitation thesis in 2007. In the years 1987÷2010
she worked in the Department of Pharmacology, Medical University of
Bialystok. For the last three years has been ahead of the Department of
Experimental Pharmacology, Medical University of Bialystok. She works as
Voivodshipl Consultant in Clinical Pharmacology. Research interests: learning
and memory, neurodegeneration and possibilities of their therapy, tumor
processes in the brain, targeted therapy. She is the author and co-author of 58
scientic articles published in the international medical journals and 80 papers
and communications presented at national and international conferences, as
well as a patent application
e-mail: hcar@umb.edu.pl, zfarmdosw@umb.edu.pl; phone:+85 748 55 54
Jan Ryszard DĄBROWSKI – Professor, is a graduate of the Institute of
Chemistry and Technology of Moscow (1977). Defended his doctoral
dissertation to the Board of the Faculty of the Technical University of
Wroclaw (1981). Habilitation thesis defended to the Council of the Institute
of Chemical Technology of the German Academy of Sciences (1989). In 2005,
the President of Poland awarded him the title of Professor. He is currently
head of the Department of Materials Science and Biomedical Engineering,
University of Bialystok. Scientic interest: tribology, biomaterials, biological
uids. He has received numerous medals and awards, including the Silver Cross
of Merit and Awards of the Minister. He is a member of many organizations
and scientic societies, including the German Society for Biomaterials Rhine-
Westphalia (NRW eV Biomaterialien AG). He is an author or co-author of
several monographs, over 200 articles in scientic and technical press and
author or co-author of more than 70 papers and communications presented
at national and international conferences.
e-mail:j.dabrowski@pb.edu.pl; phone:+85 746 92 50