Phyto mediated biogenic synthesis of gold nanoparticles using Cerasus serrulata and its utility in detecting hydrazine, microbial activity and DFT studies

Abstract

Green synthesis of Au-NPs using Cerasus serrulata (C. serrulata) leaves extract has emerged as a nontoxic and ecofriendly option, as compared to currently available chemical and/or physical methods and also Au-NPs act as both reducing and stabilizing agent. The developed Au-NPs were characterized with XRD, UV–visible spectroscopy, FTIR, SEM, TEM and chemical constituents of C. serrulata leaves extract after and before reduction of Au-NPs have been identified through GC–MS. TEM images confirmed that biosynthesized Au-NPs were spherical in shape and approximately in the range of 5–25nm. The electrochemical results showed remarkable electrocatalytic activity of the Au-NPs-modified GC electrode in the detection of environmentally hazardous pollutant like hydrazine. The modified electrode exhibits a wide linear range 5nM to 272μM with low detection limit 0.05μM. The fabricated sensor shows good selectivity towards other electroactive species as well. Thus the proposed sensor seems to be a potential candidate for developing a simple, rapid and cost-effective electrochemical sensor. The synthesized Au-NPs exhibited higher antibacterial activity against gram negative (Escherichia coli) than gram positive (Staphylococcus aureus) bacteria. DFT studies revealed that the coumarin (CM) present in the C. serrulata leaves extract demonstrated greater reducing and stabilizing properties compared to the properties of other compounds like butylhydroxytoluene (BHT) and hydrocoumarin (HCM) present in the extract.