Green Synthesis and Characterization of Silver Nanoparticles Using Citrullus lanatus Fruit Rind Extract

Michael Ndikau; Naumih M Noah; Dickson M Andala; Eric Masika

doi:10.1155/2017/8108504

Green Synthesis and Characterization of Silver Nanoparticles Using Citrullus lanatus Fruit Rind Extract

Int J Anal Chem. 2017:2017:8108504. doi: 10.1155/2017/8108504. Epub 2017 Feb 20.

Authors

Michael Ndikau¹, Naumih M Noah², Dickson M Andala³, Eric Masika¹

Affiliations

¹ Chemistry Department, Kenyatta University, P.O. Box 43844, Nairobi 00100, Kenya.
² School of Pharmacy and Health Sciences, United States International University Africa, P.O. Box 14634, Nairobi 00800, Kenya.
³ Multimedia University of Kenya, P.O. Box 30305, Nairobi 00100, Kenya.

Abstract

The wide-scale application of silver nanoparticles (AgNPs) in areas such as chemical sensing, nanomedicine, and electronics has led to their increased demand. Current methods of AgNPs synthesis involve the use of hazardous reagents and toxic solvents. There is a need for the development of new methods of synthesizing AgNPs that use environmentally safe reagents and solvents. This work reports a green method where silver nanoparticles (AgNPs) were synthesized using silver nitrate and the aqueous extract of Citrullus lanatus fruit rind as the reductant and the capping agent. The optimized conditions for the AgNPs synthesis were a temperature of 80°C, pH 10, 0.001 M AgNO₃, 250 g/L watermelon rind extract (WMRE), and a reactant ratio of 4 : 5 (AgNO₃ to WMRE). The AgNPs were characterized by Ultraviolet-Visible (UV-Vis) spectroscopy exhibiting a λ_max at 404 nm which was consistent with the spectra of spherical AgNPs within the wavelength range of 380-450 nm, and Cyclic Voltammetry (CV) results showed a distinct oxidation peak at +291 mV while the standard reference AgNPs (20 nm diameter) oxidation peak occurred at +290 mV, and Transmission Electron Microscopy (TEM) revealed spherical shaped AgNPs. The AgNPs were found to have an average diameter of 17.96 ± 0.16 nm.