Greener Synthesis of Chitosan and and#946; Cyclodextrin Thiomer Stabilized Silver Nanocomposites for Biological Applications

Abstract

x newlineAbstract newlineA biopolymer confirms the advantage of alternative potential emulsifier and stabilizer newlinein contrast to conventional chemicals in nano-chemistry. It is renewable, cost effective, newlineabundant and easily available. Furthermore, it has the additional advantage of being newlineeasily modified through simple polymer analogous reactions to the value-added newlineproducts for multi-functional efficiency. In view of the above context, the present newlineinvestigation involves microwave assisted greener method for the synthesis of newlinechitosan/and#946;-cyclodextrin based silver nanocomposites, where thiolated chitosan/and#946;- newlinecyclodextrin is itself acting as a reducing agent for silver ions. The composition and newlinestructure of the synthesized thiomer and nanocomposites were characterized by various newlinespectroscopic and microscopic techniques like FTIR, SEM, TEM, EDX and XRD. newlineThese studies indicated the homogeneity of silver nanoparticles with a size of 14.2±3.1 newlinenm in case of and#946;-cyclodextrin based silver nanocomposites, whereas in case of chitosan newlinethe size of silver nanocomposites was found ~3 nm. The modified nanocomposites newlinefunctionalized with thiol group were screened for their antimicrobial and antioxidant newlineproperties in addition to chitosan based drug delivery system. newlineThe antimicrobial results revealed excellent antimicrobial properties with a maximum newlineinhibition zone of 35 mm and MIC value of 3.7 and#956;g mL-1 in case of chitosan stabilized newlinesilver nanocomposites. On the other hand maximum inhibition zone of 37 mm and a newlineminimum MIC value of 3.7 and#956;g mL-1 were observed in case of and#946;-cyclodextrin based newlinesilver nanocomposites. Biopolymers based nanocomposites showed 99-98% reduction newlinein the bacterial growth in case of colony forming unit and optical density method newlineresults. The antioxidant properties of thiomers based silver nanocomposites and newlinethiomers were checked at three different concentrations via cyclic voltammetric newlineanalysis where thiomers have shown exceedingly enhanced antioxidant properties even newlineat 10 ppm as compared to their nanocomposites derivatives. This is ascribed to the fact newlinethat nanoparticles had acquired high effective surface area and higher percentage of newlinethiol functionalization in polymers backbone. Thiomers possessed appreciable newlineantioxidant properties ranging from 58-89%. Thiomer based nanocomposites also newlineshowed antioxidant properties but not up to the extent of their precursors 20-40%. newlineHighest modifications of thiomers were screened for their antioxidant activity with help newlineof cyclic voltammetric analysis. Where thiomers reveled antioxidant activity of 50% newlineeven at 50 ppm. newlinexi newlineChitosan based drug release system was also designed to have a command over the newlinerelease of amoxicillin trihydrate in different pH systems. Release content of drug was newlinedifferent in acidic and basic pH systems. 60% of drug was released in 1 h which is an newlineindication of fact that chitosan based system can be used to design amoxicillin newlinetrihydrate drug release system. newlineKeywords: Thiomer, Thiomer Stabilized Silver Nanocomposites, Silver newlineNanocomposites, Antimicrobial and Antioxidant Activity, Drug Release System newline