Reactive modification of gum Acacia biopolymer by natural pigment Anthocyanin and Tannin: their optical and impedance study

Abstract

ABSTRACT In this study, plant biopolymer gum Acacia is synthesised and chemically modified by fruit extract of black grapes (Vitis vinifera), eggplant (Solanum melongena). Fruits contain functional groups called chromophore which confer colour. It is the region where radiation is absorbed and electron is transferred between two energy states. They absorb UV and/or visible light. They are conjugated unsaturated bonds and responsible for optical and electrical properties. In the present work, optical properties of biopolymer gum Acacia specimen and chromophore induced specimen of the above-mentioned fruits are examined by UV-visible spectroscopy. It is found that light absorption is pronounced in the visible range of spectrum compared to the pure specimen in which absorption is found to be observed in the deep ultraviolet range. Electrical characterisation of the modified gum Acacia biopolymer with grape fruit extract and eggplant extract are observed. Electrical conductivity is enhanced over pure specimen. These properties will be fruitful in dye-sensitised solar cells (DSSCs) application, which is an ongoing extensive research area.