Microfluidics assisted green synthesis of copper oxide nanoparticles from the aqueous leaf extract of Ipomoea quamoclit L. with its antimicrobial and antioxidant activity

Abstract

Introduction

Green nanosynthesis of medicinal plants are useful for the development of antibiotic agents. In this work, we have explored the antimicrobial and antioxidant activity of green synthesised copper oxide (CuO) nanoparticles (NPs) from tropical medicinal plant Ipomoea quamoclit L.

Methods

With the aid of microfluidic technology, a low-cost, polydimethylsiloxane (PDMS) lab-on-chip micromixer for green nanosynthesis of CuO nanoparticle using Ipomoea quamoclit is presented. The UV–Vis characteristics, Fourier Transform Infra-red (FTIR) spectrum, antimicrobial and antioxidant response using DPPH and hydrogen peroxide (H₂O₂) were reported. The antimicrobial efficacy of the synthesised CuO-NPs is tested against two-gram positive bacteria Staphylococcus aureus, Micrococcus luteus, two gram negative bacteria, Enterobacter cloacae, Klebsiella pneumoniae and two fungi species Candida albicans, Aspergillus niger.

Results

UV–Vis spectrum for the synthesised CuO-NPs showed the absorbance at 670 nm, scanning electron microscope (SEM) image analysis and dynamic light scattering (DLS) analysis confirmed the presence of spherical shaped nanoparticle sized between 65 and 94.5 nm. The presence of bioactive functional groups of N-H, C-H and C=0 stretching was identified using Fourier Transform Infrared spectroscopy (FTIR). The maximum mean zone of inhibition obtained was 10.45 ± 0.25 mm for fungi A. niger. The antioxidant activity using DPPH scavenging assay and hydrogen peroxide scavenging assay showed the IC₅₀ value 33.94 μg/ml and 42.54 μg/ml respectively.

Conclusions

The obtained results reveal the potential of CuO-NPs synthesised from I. quamoclit L. as a remarkable medicinal entity for wound healing, respiratory infection, fungal infection and urinary tract infection along with the improved antimicrobial and antioxidant activity.