Silk fibroin and silver nanoparticle-based nanocomposites: Structure, processing, and emerging biomedical applications: A comprehensive review

Abstract:

Fibroin, a natural structural protein derived primarily from Bombyx mori, has emerged as a versatile biomaterial due to its unique combination of biocompatibility, biodegradability, mechanical strength, and tunable structural properties. Its hierarchical organization, consisting of β-sheet crystalline domains interspersed with amorphous regions, provides remarkable stability and functional adaptability. Recent advancements in nanotechnology have further expanded the utility of silk fibroin through the development of fibroin-based nanoparticles and nanocomposites, particularly with silver nanoparticles (AgNPs). These hybrid systems exhibit enhanced physicochemical and biological properties, including superior antimicrobial, antioxidant, and therapeutic potential. Various fabrication techniques such as electrospinning, electro spraying, solvent-induced precipitation, and supercritical fluid processing have enabled the controlled synthesis of silk fibroin nanoparticles with tailored size, morphology, and functionality. Moreover, silk fibroin serves as an efficient stabilizing and reducing agent in the green synthesis of AgNPs, overcoming issues related to nanoparticle aggregation and oxidation. The integration of AgNPs into silk fibroin matrices has demonstrated significant efficacy against pathogenic microorganisms, biofilm inhibition, and potential applications in wound healing, drug delivery, tissue engineering, and biomedical devices. This review comprehensively summarizes the structural characteristics, extraction and processing methods, nanoparticle fabrication strategies, and multifunctional applications of silk fibroin and its nanocomposites. It also highlights recent developments and future prospects in the field, emphasizing the growing importance of sustainable and biocompatible materials in advanced biomedical and technological applications.