Synthesis and Antimicrobial Activities of a Quaternary Ammonium Salt of Chitosan

Abstract

A novel quaternary ammonium salt of chitosan (QAS-CTS) was prepared through a nucleophilic substitution reaction between chitosan (CTS) and a quaternary ammonium salt (QAS), N,N-dimethyl epoxypropyl octadecyl ammonium chloride was synthesized via a quaternization reaction between N,N-dimethyl-octadecylamine (ODA) and epichlorohydrin. FTIR was employed to characterize and confirm the structures of each product. Antimicrobial tests show that QAS-CTS has higher antimicrobial activity than both CTS and QAS against either E. coli or B. subtilis. The minimum inhibitory concentrations (MIC) of QAS-CTS against E. coli and B. subtilis are 0.6 and 0.4 mg/mL, respectively.