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Polymers carrying a hydrolyzable ester function and bactericidal quaternary ammonium salts were successfully synthesized in 2 steps. The first one was the modification of hydroxyl functions of poly(vinyl alcohol) by chloroacetic anhydride. The structure of synthesized polymers was confirmed by infrared (IR), 1 H-, and 13 C-nuclear magnetic resonance (NMR). The kinetic results were consistent with a 1-order reaction, and the activation energy in the case of total modification was found to be 16.8 kJ mol Ϫ1 . The second step was the quaternization of the pendant chlorine atom with a long alkyl chain or aromatic tertiary amines. The percentage of grafting was almost total, except with 3-diethylaminophenol, probably due to steric hindrance. The thermal degradation of polymers was studied. Side chains carrying quaternary ammonium salts begin to degrade at 168°C with the emission of chloride and amine compounds. At about 250°C, acetic and chloroacetic acid are evolved due to acetate and chloroacetate side chains.

Polyamide fibers were modified for the attainment of antibacterial activity using a graft copolymerization method. The fibers were grafted with monomers containing quaternary ammonium groups using sodium persulfate as initiator. Two monomers were used as vinyl monomers.

Gelatin/chitosan particles suitable for application in ocular drug administration were prepared by a two-step cross-linking process performed in an emulsion-phase separation system. The particles were characterized by scanning electron microscopy and laser diffractometry, and the diameters were 0.202—4.596 µm. The microparticles pH-dependent behavior was monitored by their mean diameter changes in aqueous environment. Adrenalin was drug used to study loading and release characteristics. The prepared particles were nontoxic, with the DL50 values of 6.9—8.19 g/kg body mass. The in vivo biocompatibility tests consisted of subcutaneous administration of a microparticle suspension in physiological serum followed by morpho histological analysis of the implantation site. The in vivo adrenalin ocular delivery was tested on both animals and a voluntary human patient to determine the adrenalin action and by tears. The particles showed good adherent properties without irritation to the patient; adrenalin was released cleared the ocular congestion.

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