Mohd Ibran
1, Vaseem A. Ansari
1* 
, Aditya Singh
2* , Shubhrat Maheshwari
3,41 Department of Pharmacy, Faculty of Pharmacy, Integral University, Lucknow, Uttar Pradesh- 226026, India
2 Department of Pharmaceutics, Parul Institute of Pharmacy & Research, Parul University, Waghodia, Vadodara – 391760, Gujarat, India
3 Bioorganic and Medicinal Chemistry Research Laboratory, Department of Pharmaceutical Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, 211007, India
4 Department of Pharmaceutics, Parul Institute of Pharmacy, Parul University, Waghodia, Vadodara – 391760, Gujarat, India
Abstract
The potential of silver nanoparticles (AgNPs) as antimicrobial resistance fighters because of their wide-spectrum antibacterial property and multi-functional biomedical applications has made them promising nanomaterials. This review critically analyzes the recent advancements in the synthesis methods of AgNPs such as physical, chemical and green methods and highlights its effect on the physicochemical properties like size, shape, stability and biocompatibility. Unlike the traditional descriptive reviews, the present study also incorporates comparative analyses of synthesis methods based on their scalability, cost, reproducibility and toxicity. In addition, the mechanism of the antibacterial properties of AgNPs, namely the pathways of reactive oxygen species (ROS)-mediated oxidative stress, membrane disruption, inactivation of proteins, and damage to DNA are discussed in detail. Recent studies have provided quantitative information that smaller AgNPs (< 10 nm) have much greater antibacterial activity because of their greater surface reactivity and ion release. The review also examines newer biomedical applications such as wound healing, drug delivery, and anti-microbial coatings, and presents the challenges that arise with respect to toxicity, environmental issues, and clinical translation. Overall, this work offers a critical and comprehensive view of AgNPs from a synthesis property activity relationship, suggesting future research on safe and effective biomedical applications of AgNPs.