All Drug Glassy Microneedle Patches for Instantaneous Transdermal Delivery

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Nanotechnology

Background:

• Dissolving microneedles (DMNs) face challenges with drug loading and release kinetics due to polymer carriers.
• Drug crystallization within microneedles hinders formulation and efficacy.

Purpose of the Study:

• To develop carrier-free antibiotic microneedles using supramolecular engineering.
• To enhance drug loading, accelerate transdermal delivery, and improve therapeutic outcomes for biofilm-infected wounds.

Main Methods:

• Supramolecular engineering strategy utilizing synergistic drug-sulfate-water interactions.
• Fabrication of monolithic glass microneedles (GMNs) with 100% drug payload.
• In vitro and in vivo evaluation of GMNs for transdermal delivery, mechanical strength, and therapeutic efficacy.

Main Results:

• Achieved carrier-free tobramycin sulfate GMNs with 100% drug payload and high mechanical strength (5.1 GPa).
• Demonstrated instant transdermal delivery, threefold faster than polymer DMNs, with 2.6-fold accelerated diffusion.
• Showcased effective healing of biofilm-infected skin wounds and potent therapeutic effects against abscesses in vivo.

Conclusions:

• Supramolecular engineering enables robust, carrier-free glass microneedles for enhanced drug delivery.
• This approach overcomes limitations of traditional DMNs, offering improved drug loading, faster release, and potent therapeutic efficacy.
• The strategy is broadly applicable to aminoglycoside antibiotics, paving the way for next-generation transdermal platforms.