Sidra Saeed^1*, Muhammad Saleem Khan¹, Sadia Zahid², Shafiq Ur Rehman³, Muhammad Wajid¹, Islam Ashfaq¹

¹Department of Zoology, Faculty of Life Sciences, University of Okara, Okara 56130, Pakistan
²Department of Biotechnology, Faculty of Life Sciences, University of Okara, Okara 56130, Pakistan
³Department of Botany, University of Okara, Okara 56130, Pakistan

 

*Corresponding author’s email: sidrasaeed@uo.edu.pk

Received: 03 May 2026 / Revised: 25 September 2026 / Accepted: 30 October 2026 / Published Online: 01 November 2026

 

Abstract

 

Due to increasing antibacterial resistance, new antimicrobial materials are required. Metal-based nanocomposites are of interest because they may exert antibacterial effects through multiple mechanisms of action. In this study, an Ag–ZnO nanocomposite was synthesized via a chemical reduction method and characterized using XRD, FTIR, SEM, and EDX techniques. XRD results revealed the coexistence of hexagonal wurtzite ZnO and face-centered cubic (FCC) Ag phases, with an average crystallite size of approximately 15.6 nm. SEM images showed quasi-spherical agglomerated nanoparticles, while EDX analysis confirmed the presence of Ag, Zn, and O. The Ag–ZnO nanocomposite exhibited antibacterial activity against P. aeruginosa, P. chengduensis, S. aureus, and S. haemolyticus, with inhibition zones increasing with the applied volume. The differences among mean inhibition zones at various tested volumes were significant for all four bacteria by one-way ANOVA (p < 0.001; η² = 0.962–0.976). The minimum inhibitory concentration (MIC) values ranged from 0.125 to 0.50 mg/mL, with P. chengduensis showing the lowest MIC value of 0.125 mg/mL. To investigate possible interactions between the Ag–ZnO nanocluster and bacterial protein targets, molecular docking studies were performed against MurC, Sortase A and DNA gyrase B. The Ag–ZnO nanocluster showed favorable predicted interactions with all three proteins, with the most favorable docking score obtained for MurC, followed by DNA gyrase B and Sortase A. Overall, the Ag–ZnO nanocomposite showed promising antibacterial activity, while molecular docking provided exploratory insights into potential protein interactions that require further experimental validation.

 

Keywords: Ag–ZnO nanocomposite, Antibacterial activity, Minimum inhibitory concentration, Molecular docking, MurC

 

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