Formulation of an antimicrobial superabsorbent powder that gels in situ to produce reactive oxygen

摘要

The enzymatic oxidation of glucose to produce reactive oxygen species (ROS) provides honey with antimicrobial efficacy. This mechanism offers an alternative to traditional antibiotics; however, topical use of honey is limited due to its adherent and highly viscous properties. This study aims to overcome these issues by engineering a powder-based system that eases delivery and offers in situ activation of ROS.Starch based drying agents were utilised to enable freeze drying of a medical honey, with methylated-beta-cyclodextrin (MCD) enabling the highest active incorporation (70%) while still producing a free-flowing powder. Addition of a superabsorbent, sodium polyacrylate (= 40%) was shown to facilitate in situ gelation of the powder, with an absorption capacity of up to 120.7 +/- 4.5 mL g(-1).Promisingly efficacy of the optimised superabsorbent powder was demonstrated in vitro against several clinically relevant Gram-negative and Gram-positive bacteria (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa). Alongside this no adverse effects were observed against human dermal fibroblasts. Application of the superabsorbent powder in an ex-vivo porcine wound model revealed capability to form a protective hydrogel barrier in less than 1 min. Overall, this novel ROS producing superabsorbent powder has potential to tackle topical infections without using traditional antibiotics.