A self-regulating antimicrobial model based on the ion-exchange stimuli

Abstract

In this study, a novel intelligent antimicrobial model was constructed based on the antibiotic properties of nano-silver and the ion-exchange response of dehydrated alginate (Alg) gel. Through the process of reducing reaction, hydrogel formation and dehydration, the model composed of Alg and nano-silver was fabricated. The distinguished feature of this model lies in its antimicrobial properties and biocompatibility. In this model, the releasing level of nano-silver is determined by the outside-in swelling of Alg composites, which is further self-regulated by the volume of wound exudates. The results showed that the released nano-silver was intelligently maintained within a constant concentration range, so that it could be further designed to exhibit antimicrobial activity without cytotoxicity. Furthermore, the murine wound infection model conducted with these composites resulted in a significant decrease of bacteria number. The self-regulating swelling feature based on the ion-exchange response of Alg along with the controlled release of nano-silver made this composite a promising intelligent model for antimicrobial wound dressing applications.

Smart Bandages: The Future of Wound Care

“…In addition, we will highlight some of the sensors and active drug delivery systems that have been developed for wound care, along with automated systems that can both sense and respond to relevant wound parameters. There has been significant progress in the development of smart materials that can respond to the variations in the wound environment, such as upregulation of inflammatory markers, variation in ionic concentration, temperature, or changes in the environmental pH [8, 28]. However, these systems cannot be actively controlled.…”

Intrinsic stimuli‐responsive nanocarriers for smart drug delivery of antibacterial agents—An in‐depth review of the last two decades

“…Examples of these polymers include poly(N‐vinyl caprolactam), PNIPAM, and poly(vinyl ether) (Raza et al, 2019). Currently, to the best of our knowledge, a Na + ‐sensitive alginate gel loaded with nano‐silver as a non‐specific antimicrobial agent for wound dressing applications is the only reported ionic‐responsive nanocarrier in antibacterial application (X. Huang et al, 2015).…”

“…Interestingly, only one ionic microenvironment‐responsive nanoparticle has been reported to have antibacterial efficacy. X. Huang et al (2015) created a novel biocompatible nanosilver and alginate model with activity against S. aureus . In this study, the volume of wound exudates regulates the swelling of alginate composites, which in turn govern the drug release of nanosilver.…”

A review on smart bioresponsive drug delivery systems

“…For instance, Na+ ion commonly exists in the wound exudates. Huang et al described a Na+sensitive alginate gel loaded with nano-silver as a nonspecific antimicrobial agent forwound dressing applications [24]. Upon administration to the wound, the alginate gel swelled due to the ion-exchange of Na+, result in subsequent release of nano-silver.…”