In vitro and in vivo assessment of polymer microneedles for controlled transdermal drug delivery

Abstract

Microneedles (MNs) system for transdermal drug delivery has the potential to improve therapeutic efficacy, proving an approach that is more convenient and acceptable than traditional medication systems. This study systematically researched dissolving polymer MNs fabricated from various common FDA-approved biocompatible materials, including gelatine, chitosan, hyaluronic acid (HA) and polyvinyl alcohol (PVA). Upon application of MN patches to the porcine cadaver skin, the MNs effectively perforated the skin and delivered drugs to subcutaneous tissue on contact with the interstitial fluid. Both the in vitro and in vivo drug release tests showed the similar trends but different release rates among the prepared MNs. Interestingly, the drug-release kinetics of PVA MNs were able to be altered by changing the molecular weight. To evaluate the feasibility using the proposed MNs for treating diabetes, an in vivo insulin absorption study in diabetic mice was performed. The results showed different insulin release properties of MNs fabricated from various kinds of polymer, leading to different decrease in blood glucose levels. We made a systematic and comprehensive study of some drug-loaded polymer MNs, and anticipated that dissolving polymer MNs have potential to improve therapeutic efficacy through controlled drug release.

Keywords:

• Microneedle
• controlled release
• drug delivery
• polymers

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China [51673019, 51473017], the Fundamental Research Funds for the Central Universities [buctrc201406], the Innovation and Promotion Project of Beijing University of Chemical Technology, and the long-term subsidy mechanism from the Ministry of Finance and the Ministry of Education of PRC.