ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 1, pp. 128!130. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + N.A. Gushchin, G.U. Ostrovidova, E.A. Sosnov,2008, published in Zhurnal Prikladnoi Khimii, 2008, Vol. 81, No. 1, pp. 132!135.
AND POLYMERIC MATERIALS
Antimicrobial Polymeric Composite Films for Medical Use
N. A. Gushchin, G. U. Ostrovidova, and E. A. Sosnov
St. Petersburg State Institute of Technology (Technical University), St. Petersburg, Russia
Received June 28, 2007
Abstract-Preparation of prolonged-action antimicrobial polymeric films based on polyvinyl alcohol and
carboxymethyl cellulose sodium salt (Na-CMC), modified with chlorohexidine, is studied. The effects of Na-
CMC on the adsorption capacity, degradability, and specific weight of the electrodeposited film are examined.
Modification of polymers with bioactive com-
pounds (BACs) has attracted a great interest in view
of the development of immobilized biocatalysts, bio-
regulators, and prolonged-action drug dosage forms.
Many up-to-date therapeutic agents are charac-
terized by a short durability because of ineffective
drug formulation. Therefore, one has to repeatedly
take a medicine, increasing the hazard of overdose and
side effects .
The use of BACs immobilized on biocompatible
polymers allows solution of this problem by increas-
ing duration of prolonged action through controlled
degradation of the polymeric support, by ensuring
desired BAC liberation kinetics via control of the
chemical composition of the carrier, and by providing
a convenient drug dosage form via optimization of
the polymer matrix.
The existing methods for modification of polymeric
films with BACs do not always provide a prolonged
effect of the immobilized BACs. For example, poly-
vinyl alcohol (PVA) films modified with immobilized
protease C and polyhexamethyleneguanidine hydro-
chloride lose their enzymatic activity in 233 h and
antimicrobial activity, in a day .
Electroforming shows promise as a method for
preparing films of water-soluble polymers with simul-
taneous immobilization of bioactive components .
The method allows thickness-controlled preparation of
film coatings of a complex composition. Furthermore,
this is a time-saving method, which can be realized
under mild conditions. The latter is particularly sig-
nificant for BACs, as they are sensitive to elevated
temperature and immobilization time.
Water-soluble polymers commonly used for film
formation showed themselves for many years in
medicine and pharmaceutics as nontoxic and highly
biocompatible materials [43 6].
Here we report on preparation and characterization
of prolonged-action antimicrobial polymeric films
based on polyvinyl alcohol (PVA) and carboxymethyl
Polymeric films were prepared from polyvinyl
alcohol [PVA, 16/1 grade; MW ~ 40000; GOST
(State Standard) 10 779378] and carboxymethyl cellu-
lose sodium salt [Na-CMC, Kamtsel-0 grade; MW
~120 000; TU (Technical Specifications) 2231-002-
50 277 563-00]. Boric acid (GOST 9656375) was used
as a cross-linking agent. To impart antimicrobial ac-
tivity, chlorohexidine (CH) (000 P no. 000 734/01)
was introduced into the formulation. The hydrogel
was electroformed on a Si(111) support.
Chlorohexidine is widely used in medicine .
This antiseptic agent, taken in a concentration above
0.01%, demonstrates a strong bactericidal activity
against most gram-positive and gram-negative aerobes
and anaerobes, and fungicidal and antiviral activities
The CH concentration was determined spectro-
photometrically at l = 253 nm. The antimicrobial ac-
tivity of immobilized CH was measured in the agar-
diffusion test  using Staphylococcus citreus as
a test culture.
To improve the elastic characteristic of the films,
3 wt % glycerol (GOST 6259375) was added into the
formulation as a plasticizer .
The basic film-forming component is PVA [12, 13].
The film cannot be electroformed from a formulation
containing only Na-CMC.
The presence of Na-CMC considerably increases
the specific weight of the film deposited on the elec-
trode (Fig. 1, curves 2, 3
). In aqueous Na-CMC, asso-