Antimicrobial hydrogel foam dressing with controlled release of gallium maltolate for infection control in chronic wounds

Effective treatment of infection in chronic wounds is critical to improve patient outcomes and prevent severe complications,including systemic infections,increased morbidity,and amputations.Current treatments,including antibiotic administration and antimicrobial dressings,are challenged by the increasing prevalence of antibiotic resistance and patients’sensitivity to the delivered agents.Previous studies have demonstrated the potential of a new antimicrobial agent,Gallium maltolate(GaM);however,the high burst release from the GaMloaded hydrogel gauze required frequent dressing changes.To address this need,we developed a hydrogel foambased wound dressing with GaM-loaded microspheres for sustained infection control.First,the minimal inhibitory and bactericidal concentrations(MIC and MBC)of GaM against two Staphylococcus aureus strains isolated from chronic wounds were identified.No significant adverse effects of GaM on dermal fibroblasts were shown at the MIC,indicating an acceptable selectivity index.For the sustained release of GaM,electrospraying was employed to fabricate microspheres with different release kinetics.Systematic investigation of loading and microsphere size on release kinetics indicated that the larger microsphere size and lower GaM loading resulted in a sustained GaM release profile over the target 5 days.Evaluation of the GaM-loaded hydrogel dressing demonstrated cytocompatibility and antibacterial activities with a zone of inhibition test.An equine distal limb wound model was developed and utilized to demonstrate the efficacy of GaM-loaded hydrogel foam in vivo.This antimicrobial hydrogel foam dressing displayed the potential to combat methicillin-resistant S.aureus(MRSA)infection with controlled GaM release to improve chronic wound healing.

Challenges and innovations in treating chronic and acute wound infections:from basic science to clinical practice

Acute and chronic wound infection has become a major worldwide healthcare burden leading to significantly high morbidity and mortality.The underlying mechanism of infections has been widely investigated by scientist,while standard wound management is routinely been used in general practice.However,strategies for the diagnosis and treatment of wound infections remain a great challenge due to the occurrence of biofilm colonization,delayed healing and drug resistance.In the present review,we summarize the common microorganisms found in acute and chronic wound infections and discuss the challenges from the aspects of clinical diagnosis,non-surgical methods and surgical methods.Moreover,we highlight emerging innovations in the development of antimicrobial peptides,phages,controlled drug delivery,wound dressing materials and herbal medicine,and find that sensitive diagnostics,combined treatment and skin microbiome regulation could be future directions in the treatment of wound infection.