Hierarchically porous MOF-based microneedles for glucose-responsive infected diabetic wound treatment

Elaborately designed stimuli-responsive antibacterial systems are highly desirable for infected diabetic wound treatment. Herein, hierarchically porous metal-organic framework (MOF)-based glucose-responsive microneedles (MNs) were designed for painless transdermal wound treatment. For the first time, a hierarchically porous MOF was applied for consuming the surplus glucose to protect infected diabetic wounds from bacterial infection. Through one-pot synthesis, glucose oxidase (GOx) was firstly encapsulated into a Fe-doped zeolitic imidazolate framework (ZIF), and based on a properly controlled tannic acid (TA) etching process, the hierarchically porous MOF (GOx@Fe-ZIF-TA) was constructed afterwards. GOx encapsulated in GOx@Fe-ZIF-TA could consume surplus glucose in infected diabetic wounds to yield gluconic acid and H2O2. The latter could be catalyzed by Fe(ii) to generate antibacterial OH, which would not result in antimicrobial resistance. The as-obtained hierarchically porous MOF revealed satisfactory glucose-responsive antibacterial activity, and the hierarchically porous MOF-based MNs showed enough stiffness for penetration. This study offers a new strategy, using hierarchically porous enzyme-loaded MOFs as depots to integrate with MNs, for designing stimuli-responsive transdermal systems for the treatment of infected diabetic wounds and other diseases.

Automated summary

Hierarchically porous metal-organic framework (MOF)-based glucose-responsive microneedles (MNs) were developed for the treatment of infected diabetic wounds. The MOF can consume surplus glucose and generate antibacterial substances, showing satisfactory antibacterial activity.