关键词: 壳聚糖季铵盐, 有机累托石, 纳米复合材料, 抗菌

Abstract: Quaternized chitosan, N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) was synthesized and intercalated into organic rectorite (OREC) to prepare the nanocomposites via solution intercalation method. When the mass ratio of HTCC to OREC was 2∶1, the nanocomposite with the largest interlayer distance of 4.8nm was obtained. Two in vitro antimicrobial assays indicated that all the nanocomposites exhibited strong inhibition effect under weak acid, water and weak basic condition. Moreover, with increasing the amount or the interlayer distance of OREC, the antimicrobial activity was stronger. The lowest minimum inhibition concentrations (MIC) of the nanocomposites against Grampositive bacteria, Gram-negative bacteria and Fungus were 1/32-1/8, 1/8-1/2 and 1/16-1/8 of that for quaternized chitosan or OREC, respectively. MIC values of the nanocomposites against Staphylococcus aureus and Bacillus subtilis were less than 0.00313% (W/V) in all media tested. The nanocomposites can kill 90% Staphylococcus aureus and 80% Escherichia coli in 30min. The mechanism of the antimicrobial action was briefly discussed on the base of TEM and SEM results.

Key words: quaternized chitosan, organic rectorite, nanocomposite, antimicrobial activity