Synthesis, characterization, and molecular docking analysis of Chitosan-gr-Polysulphanilic acid as antimicrobial water-soluble polymers

As a hydrophilic polysaccharide derived from chitin, chitosan has a broad antibacterial spectrum against bacteria and fungi. Activity depends on polymer molecular weight (MW) and degree of acetylation (DA). The activity of polysulphanilic acid as an antimicrobial is very poor. Chitosan graft polysulphanilic acid was synthesized and characterized by some instrumental tools, such as UV-visible, IR spectroscopy, SEM, XRD, and TGA. The obtained graft was introduced to use as an antimicrobial. The obtained data reveals a good antimicrobial activity for different types of the organism as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. For the effect of chitosan, three antibacterial mechanisms are proposed. The ionic surface interaction results in wall cell leakage the inhibition of the mRNA and protein synthesis via the penetration of chitosan into the nuclei of the microorganisms; and the formation of an external barrier, chelating metals, and provoking the suppression of essential nutrients to microbial growth. It is likely that all events occur simultaneously but at different intensities. Chitosan-graft-polysulphanilic acid as a water-soluble polymeric material gives higher efficiency than chitosan and the used references for both gram-positive and gram-negative bacteria. Also, The molecular docking analysis showed that Chitosan-gr-Polysulphanilic acid interacts with the five receptors via different types of interactions, such as hydrogen bonding, van der Waals, and pi-interactions with high binding energies. Also, Chitosan-graft-poly sulphanilic acid has better ADMET and physicochemical properties. So, Chitosan-graft-poly sulphanilic acid can be used as an antimicrobial agent.