Chemical Copolymerization and Characterization of Colloidal Poly(aniline‐co‐3‐aminobenzoic acid) as a High‐Performance Antibacterial Polymer

Abstract

ABSTRACTPolyaniline (PAn) and copolymer of aniline with 3‐amino benzoic acid was synthesized by dispersion polymerization in the presence of ammonium peroxydisulfate as an oxidant and hydroxypropylcellulose as a stabilizer. The product polymers were characterized by a number of techniques including UV–vis, Fourier transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy, and thermal gravimetric analysis. The prepared polymer was then tested for the antibacterial properties against Gram‐negative bacteria; (E. coli (PTCC 1398) and P. aeruginosa (PTCC 1310)) and Gram‐positive bacteria (S. aureus (ATCC 25923)). The antibacterial properties were assessed by the disk diffusion method, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The results clearly showed that colloidal PAn strongly inhibits the growth of wild‐type E. coli (19 ± 0.5 mm) followed by P. aeruginosa (17 ± 0.5 mm) and S. aureus (17 ± 0.5 mm) bacteria. Poly(aniline‐co‐3‐aminobenzoic acid) (PAn3ABA) in comparison with the pristine PAn showed moderate antibacterial activity against E. coli (11 ± 0.5 mm) followed by P. aeruginosa (10 ± 0.5 mm) and S. aureus (7 ± 0.5 mm). It was found that the MIC values of colloidal PAn and PAn3ABA against E. coli were 0.62 and 1.25 mg/mL, respectively. In addition, the MBC value of colloidal PAn and PAn3ABA against E. coli was of same value (1.25 mg/mL).