Beta-cyclodextrin-based in situ forming micro-particle for intra-periodontal pocket antimicrobial drug delivery

Abstract

Doxycycline hyclate (DH) is the drug of choice practically be administered for local periodontitis treatment. The DH-loaded in situ micro-particle (ISM) using beta cyclodextrin (β-CD) as the matrix base for intra-periodontal pocket drug delivery was focused in this study. The non-aqueous in oil injectable emulsion was prepared using a two-syringe connector system. The stable emulsion was obtained when the internal phase contained 5% w/w DH with 35% w/w β-CD dissolved in N-methyl pyrrolidone (NMP) and the external phase contained 7.5% w/w glycerol monostearate (GMS) dispersed in olive oil. The pH and viscosity of this system were 3.54 ± 0.14 and 207.03 ± 7.56 cPs, respectively, with a pseudo-plastic flow and suitable injectable manner for intra-periodontal injection. The transformation from emulsion into a DH-loaded β-CD micro-particle was rapid after contact with simulated crevicular fluid. The transformation rate was slightly higher than the solvent diffusion rate from the solvent exchange mechanism. The prolonged DH release from β-CD micro-particle was attained after tested with the dialysis tube method and showed efficient antimicrobial activities especially against Porphyromonas gingivalis. This investigation indicated the potential application of β-CD as the matrix for ISM for the development of local drug delivery system for periodontitis treatment.