Facile minocycline deployment in gingiva using a dissolvable microneedle patch for the adjunctive treatment of periodontal disease

Minocycline is a commonly used drug for adjunctive therapy in periodontal disease. However, the current mainstream local medications primarily rely on intra-pocket administration, which, while avoiding the side effects of traditional systemic drugs, presents challenges such as inconvenience, discomfort, and the need for professional assistance, thus affecting patient compliance. Herein, we introduce a minocycline-loaded dissolvable microneedle (Mino-DMN) patch that allows for local and efficient delivery of minocycline to gingiva for the treatment of periodontitis. A two-step casting micro-molding process involving vacuum drying and freeze drying is employed to concentrate minocycline in the microneedle part and limit its diffusion into the patch backing. The resulting Mino-DMN patch features an array of minocycline-enriched gelatin MNs with a porous HA patch backing. The microneedles can penetrate into gingiva with enough mechanical strength and quickly release minocycline into the gingival tissue, ensuring prolonged local residence of the drug and minimizing its loss to saliva. In vivo experiments show Mino-DMN inhibits pro-inflammatory factors, promotes anti-inflammatory factors, and stimulates bone formation, surpassing topical application and comparable to the inconvenient and discomfort administration of Periocline®. This proposed Mino-DMN offers a simple, efficient, user-friendly strategy for the adjunctive treatment of periodontal disease.