Transdermal drug delivery systems hold promise, but their effectiveness is often constrained by the skin’s barrier. Microneedles (MNs) improve drug permeability by creating micro-channels in the skin, yet they continue to face challenges such as infection risks and safety concerns. To overcome these challenges, a novel antimicrobial sponge MNs (ASMNs@PVP-INS) modified with polyvinylpyrrolidone (PVP) for insulin (INS) delivery was designed. Mechanical testing demonstrated that these MNs possess excellent mechanical strength, capable of withstanding at least 0.11 N per needle without rupture. In vitro drug penetration tests revealed that the MNs consistently released over 75 % of INS within a 6 h. In an animal model, ASMNs@PVP-INS reduced initial blood glucose levels from 22.4 to 5.72 mmol/L, effectively maintaining glucose control for more than 6 h without inducing hypoglycemia. Additionally, agar diffusion assays indicated that INS loading did not compromise the antimicrobial properties of antimicrobial sponge MNs (ASMNs). Skin irritation tests showed that ASMNs@PVP-INS exhibited mild irritation (PII < 0.6), with skin damage fully recovering within 8 h. Safety assessments indicated no significant toxicity to mice, with biochemical markers remaining within normal ranges, thereby confirming their good biocompatibility. In conclusion, ASMNs@PVP-INS hold promise as a novel drug delivery vehicle.
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