Polyamide‐montmorillonite nanocomposites as a drug delivery system: Preparation, release of 1,3,4‐oxa(thia)diazoles, and antimicrobial activity

Abstract

New microbicidal polyamides were prepared by the reaction of 5-phenyl-1,3,4,-oxadiazole-2-thiol, 5-phenyl-1,3,4-oxadiazole-2-amine, and 5-(4-chlorophenyl)21,3,4-thiadiazole-2-thiol with ethyl chloroformate followed by polycondensation with polyoxypropylenetriamine (Jeffamine T 403 ). The polyamides were modified to yield amine hydrochloride. The intercalation of polyamides into montmorillonite (MMT) was achieved through an ion exchange process between sodium cations in MMT and amine hydrochloride in the polyamides. The structure of the resulting materials was characterized with elemental analysis, proton nuclear magnetic resonance, Fourier transform infrared-spectroscopy, X-ray diffraction, thermogravimetric analysis, and transmission electron microscope. The release behavior of 1,3,4-oxa(thia)diazoles was investigated in buffered aqueous solution at different pH values (2.3, 5.8, and 7.4). A slow release was recorded from the nanocomposites whereas; the release reaches almost 90% from polyamides. The in vitro antimicrobial activity of the polyamides and nanocomposites was studied against Gram-negative bacteria, Gram-positive bacteria, Yeast and the filamentous fungi by well diffusion method. The polymers showed good or moderate antimicrobial activities. However, nanocomposites showed no antimicrobial effect. Furthermore, in vivo study showed that nanocomposites had good antimicrobial activity.

Clay nanocomposites as engineered drug delivery systems

“…Although in vitro studies showed no antimicrobial effect, in vivo studies suggest that nanocomposites offer good antimicrobial activity. 72 New nano hybrid materials based on a combination of montmorillonite and pH sensitive positive charges polymer for encapsulating drugs to produce inorganic-organic nanocomposite are able to act as effective drug delivery systems (DDS). In this approach, the ionic liquid monomers are intercalated into montmorillonite and subsequently copolymerized with methacrylic acid.…”

Application of montmorillonite in bentonite as a pharmaceutical excipient in drug delivery systems

“…Moreover, similar to alginate film, incorporating montmorillonite increased tensile strength and decreased degradation and drug release rates of a polyester polyol acrylate-based film (Thatiparti et al 2010). Polyamide and polyacrylamide have also been studied as montmorillonite-mixed formulations (Kevadiya et al 2013;Salahuddin et al 2014).…”

5‐Phenyl‐1,3,4‐oxadiazole‐2‐thiol/polyamide‐montmorillonite microbicides nanocomposites as drug delivery system

“…Sustained release was observed from the nanocomposites. In vivo studies showed that nanocomposites offer good antimicrobial activity . In this study, different ratios of 5‐phenyl‐1,3,4‐oxadiazole‐2‐thiol was loaded into 2,3‐dihydroxysuccinate, then reacted with Jeffamine (T 403 ).…”