Biocidal Polymers: Synthesis, Characterization and Antimicrobial Activity of Bis-Quaternary Onium Salts of Poly(aspartate-<i>co</i>-succinimide)

• Main Authors: Mohamed H. El-Newehy, Meera Moydeen A., Ali K. Aldalbahi, Badr M. Thamer, Yehia A.-G. Mahmoud, Hany El-Hamshary
• Format: Article
• Language: English
• Published: MDPI AG 2021-12-01
• Series: Polymers
• Subjects: quaternary salts; antimicrobial activity; water-soluble polymers; poly(aspartate-<i>co</i>-succinimide)
• Online Access: https://www.mdpi.com/2073-4360/13/1/23

Microbial multidrug resistance presents a real problem to human health. Therefore, water-soluble polymers based on poly(aspartate-<i>co</i>-succinimide) were synthesized via reaction of poly(aspartate-<i>co</i>-succinimide) with bis-quaternary ammonium or quaternary salts. The resultant copolymers were characterized by various techniques such as FTIR, TGA, ¹HNMR, ¹³CNMR and elemental microanalysis. Antimicrobial activities of the new onium salts were investigated against <i>Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus</i>, <i>and Salmonella typhi,</i> and the fungi; <i>Candida albicans,</i><i>Aspergillus niger</i>, <i>Cryptococcus neoformans</i> and <i>Aspergillus flavus</i> by agar diffusion method. Antimicrobial activity was studied in terms of inhibition zone diameters, in addition to the estimation of minimal inhibitory concentration (MIC) of the prepared compounds. <i>A. niger</i> and <i>E. coli</i> were the most affected microorganisms among the tested microorganisms with an inhibition zone of 19–21 (mm) in case of biocides, (V) and (VII). The obtained results showed that the quaternary onium salts have higher activity compared to the aspartate copolymer with MIC concentrations of 25 mg/mL for (VII) and (V) and 50 mg/mL for (VI) and (IV).