AccScience Publishing / ITPS / Volume 4 / Issue 2 / DOI: 10.36922/itps.v4i2.70

Conjugation of Silver and Gold Nanoparticles for Enhancing Antimicrobial Activity

Muhamad Shakir Yusoff1 Subash C. B. Gopinath1,2,3* M. N. A. Uda1 Thangavel Lakshmipriya2 Ahmad Radi Wan Yaakub1 Periasamy Anbu4*
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1 Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia
2 Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Perlis, Malaysia
3 Centre of Excellence for Nanobiotechnology and Nanomedicine, Faculty of Applied Sciences, AIMST University, Semeling, Kedah 08100, Malaysia
4 Department of Biological Engineering, Inha University, Incheon – 402-751, South Korea
INNOSC Theranostics and Pharmacological Sciences 2021, 4(2), 38–47;
Submitted: 2 February 2022 | Accepted: 8 April 2022 | Published: 22 April 2022
© 2022 by the Authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution -Noncommercial 4.0 International License (CC-by the license) ( )

Silver and gold nanoparticles are promising agents that can enhance the antibacterial activity of conjugated/capped extract of plant compounds. The aim of our study is to synthesize silver nanoparticles from Gymnema sylvestre plant extract. In this study, the antimicrobial activity of conjugated silver which was green synthesized and gold nanoparticle that was obtained from a commercial source was evaluated using disk-diffusion method against Escherichia coli and Aspergillus niger. Transmission electron microscopy, scanning electron microscopy, ultraviolet-visible spectroscopy, and Fourier transform infrared spectroscopy analyses were also carried out to characterize the conjugated silver and gold nanoparticles. The conjugation of silver and gold nanoparticles was performed chemically using 16-mercaptodecanoic acid. Our results revealed that conjugated silver and gold nanoparticle both showing larger inhibition zones against E. coli and A. niger. The minimum inhibitory concentration (MIC) of the above metallic conjugation was found to be stable with MIC was reported to be 1 mM. When comparing the sample analysis on conjugation of gold and silver nanoparticles against E. coli and A. niger, the antimicrobial activity recorded was 2.0 ± 0.01 and 2.32 ± 0.04 cm, respectively, with no significance difference was found (P = 0.85). In conclusion, the combination of two different nanoparticles is efficient for microbial inhibition and can be useful for studying antimicrobial activities with the combination of different nanomaterials in future.

Surface morphology

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Conflict of interest
There is no conflict of interest to declare.
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INNOSC Theranostics and Pharmacological Sciences, Electronic ISSN: 2705-0823 Published by AccScience Publishing