Organic Montmorillonite Intercalated Nano-composites Prevent Post-Surgical Associated Infections

Zahra Rezvani,Masoud Mozafari,Mazaher Gholipourmalekabadi,Saeid Kargozar,Peiman Brouki Milan

doi:10.5185/amlett.2020.021471

Abstract

In this study, organic montmorillonite (OMMT) is a modified form of montmorillonite (MMT) in which chitosan (CS) intercalated MMT by ion exchange of sodium ions from Na/MMT with –NH3 + of CS. The structural analysis confirmed intercalation of CS into MMT layers, indicating that CS molecular chains incorporated into the MMT layers. The interlayer distance of the MMT layered was 1.128nm and in the OMMT layers enlarged to 2.365 nm. Antibacterial activity analysis showed that unmodified MMT could not inhibit the growth of bacteria. Nevertheless, after addition of the CS molecules, an increase in the interlayer distance of MMT was observed. No difference was observed between the viability of the human dental pulp stem cells (hDPSCs) contacted to different concentrations (ranging from 0.5 to 2mg/ml) of MMT and OMMT in all time intervals, when compared with the control samples. Furthermore, neither MMT nor OMMT showed apoptosis and cytotoxicity effect on the cells. The strong antibacterial activity of the synthesized OMMT nanocomposite was also confirmed against E. coli, S. aureus, K. pneumonia and P. aeruginosa, suggesting its high potential for the prevention of post-surgical infections.

Highlights

Polymer/clay composites have received much more attention since they showed enhanced characteristics such as conductivity, dye adsorption and antibacterial activity
The antibacterial activity of the prepared samples against four ATCC bacteria (P. aeruginosa, S. aureus, E. coli and K. pneumonia) was determined by the Kirby-Bauer disk diffusion test [7] according to Clinical Laboratory Standards Institute (CLSI) 2013 guidelines [6]
It was expected that –NH3+ groups of CS could effectively cooperate electrostatically with the negatively charged groups in the MMT, shown in (Fig. 1(b)). This phenomenon confirms that an ionic exchange reaction occurred between CS and Na/MMT and that CS was intercalated into the MMT layers [3,9]

Summary

Introduction

Polymer/clay composites have received much more attention since they showed enhanced characteristics such as conductivity, dye adsorption and antibacterial activity. The antibacterial activity of the prepared samples against four ATCC bacteria (P. aeruginosa, S. aureus, E. coli and K. pneumonia) was determined by the Kirby-Bauer disk diffusion test [7] according to Clinical Laboratory Standards Institute (CLSI) 2013 guidelines [6]. The leading bands in the CS spectrum were basically as a result of stretching vibrations of OH groups at 3437cm-1. Absorption in the range of 1261cm-1, (1082-1158) cm-1 were showed (C-O-H) and (C-O-C) stretching vibration in CS.

Results

Conclusion