Abstract

Antimicrobial polymers can be synthesized in many methods. They can be further modified to alter their
action toward microbes. N-vinylpyrrolidone (NVP) is biocompatible monomer which on copolymerization
can form an antimicrobial copolymer. Acrylic acid (AA) is an unsaturated carboxylic acid which under
goes copolymerization. The carboxylic acid functional group introduces an antimicrobial property to the
copolymer formed. Maleic anhydride (MA) is another monomer that can be used to make the copolymer as
antimicrobial. On hydrolysis, it becomes dicarboxylic acid. These two copolymers differ by one carboxylic
acid group. These copolymers are further esterified with N,N-diethylaminoethanol (DEAE). This introduces
amino group into the copolymer and the antimicrobial property will be enhanced. The copolymers of (NVP-
AA) and (NVP-MA) are synthesized by free radical copolymerization. Further they are esterified with DEAE.
The resulting copolymers and macro-complexes are characterized by Fourier-transform infrared and nuclear
magnetic resonance spectral studies. The antimicrobial properties of these are studied by Agar well diffusion
method. The studies are made on the Gram-positive bacteria Staphylococcus aureus - 3160 and Bacillus
pumilus - 1640, Gram-negative bacteria Escherichia coli - 45 and Enterobacter aerogenes - 2822, and two
fungal strains Fusarium oxysporum - 2087 and Aspergillus niger - 4325. The standard antibacterial used
was streptomycin sulfate. The standard antifungal used was fluconazole. The inhibition zones formed are of
considerable diameter. These copolymers and macro-complexes may be used as a substituent for the standards
used.