Development of silver nanoparticle-chitosan composite film for determination of total antioxidant capacity of some fruit juices and plant extracts

Abstract

In this study, a silver nanoparticle-chitosan (AgNPCh) composite film was developed for the determination of antioxidant capacity of polyphenolic compounds. The optimum conditions of solid nanosensor based on chitosan-based polymeric membranes containing AgNPs such as content of the composite film, pH and incubation time were idendified. The sensor measurement is based on the fact that the addition of polyphenols to the sample solution increases the absorption of Ag(0) NPs, which exhibit a characteristic plasmon absorption band at a wavelength of 423 nm and the developed method exhibits a linear variation versus the concentrations standard polyphenolic compounds. The method was applied to the apple, peach, cherry, grape and pomegranate juices and rosemary, marjoram and sage plant extracts. This sensor may be an alternative to conventional spectroscopic methods to design portable, low-cost, simple and easy-to-use field analyses without the need for special equipment for the determination of antioxidant capacity of polyphenolic compounds.