Green synthesis of gold nanoparticles (Elixir of Life) from banana fruit waste extract - an efficient multifunctional agent

A simple, one step, rapid green chemical method for the room temperature reduction of hydrogen tetrachloroaurate(III) hydrate (HAuCl4 center dot 3H(2)O) by the extract of banana fruit waste (BFW) is described here. This method illuminates the multi-functionality of BFW extract as a novel reducing, capping and stabilizing agent for the synthesis of the Elixir of Life i.e. gold nanoparticles (AuNps), additionally no physical or chemical agents were used. The biosynthesized AuNps have diverse shapes; the majority were spheres found by FE-SEM and AFM analysis. The average size of the circular AuNps observed was <20 nm during HR-TEM analysis. The particles showed better crystallinity with the FCC plane evident from the XRD patterns. Superb rough surface of the AuNp film was apparently proved by AFM. The biomolecules responsible for the reduction, capping and stabilization were pointed out using FTIR. The rationality of the work is the use of waste for the production of high value AuNps. The overall work covers three out of the twelve fundamental principles of green chemistry and one out of twelve principles of green engineering.