Paper Title
Novel Benzimidazole Modified Chitosan as Antimicrobial Biomaterial and Effective Hg Sensing for Sequestration

Abstract
Chitosan modified with 4-(1H-benzo[d]imidazol-2-yl)-2-chlorophenol (ligand 1) selectively senses Hg ions only in the presence of other metal ions competitively. The heavy metal (Hg) was effectively sensed even in the low range of concentrations (5 ppm to 25 ppm). The sensing of Hg by the free ligand 1 was observed through colorimetric and UV-Vis spectroscopy. The adsorption of Hg on modified chitosan was followed by ICPOES. The ligand 1 based chitosan modification and the nanoparticle formation were characterized by FTIR, XRD, 1H NMR, AFM and SEM techniques. The antimicrobial property of ligand 1, modified chitosan and pure chitosan were compared based on their activity towards bacterial species Escherichia coli, Salmonella typi and Bacillus subtili and the fungi, Candidaalbicans. The modified chitosan showed less antimicrobial activity than the pure ligand but more activity in comparison with the pure chitosan. Keywords— Benzimidazole, Chitosan, Mercury, Colorimetry, Antimicrobial activity.