Insulin-infused bimetallic nano-subclusters as a multifunctional agent for ROS scavenging, antibacterial resilience, and accelerated in vitro cell migration

Abstract

This is the first report on the synthesis and wound healing application of green synthesized insulin-infused bimetallic (copper–silver) nano-subclusters (ICu–AgNSCs) with high stability, aqueous solubility, biocompatibility, and target specificity. HRTEM and SAED data confirm octahedral particles (with a diameter of 9.6 ± 2.2 nm) composed of discrete copper clusters on the periphery and a silver core that are further infused with an insulin corona (0.5 ± 0.2 nm), as confirmed by the characteristics of Cu–OH and Ag–O stretching bonds and alteration in insulin amide bonds. The ICu–AgNSCs had high insulin loading efficiency (93.90 ± 1.05%) and a high drug release rate (92.69 ± 0.90% within 40 h), making them ideal for sustained release applications. Wound healing in diabetic conditions gets delayed due to the prolonged proinflammatory phase and microbial infestation, which may lead to clinical amputation. Therefore, advanced therapeutics that promote cell growth by reducing inflammation and microbial growth are required. ICu–AgNSCs may satisfy all these criteria. Insulin and quercetin have ROS scavenging and anti-inflammatory properties. Insulin and copper have cellular growth-promoting activity; additionally, silver has antimicrobial properties. ICu–AgNSCs have been shown to accelerate diabetic cell migration in vitro, making them an ideal choice for pre-clinical and clinical applications.