3D polymer microneedle array: Fabrication and analysis

A lot of research has been done on the development of Microneedles (MNs) to be used as medical devices with an aim to have painless transdermal drug and improved vaccine delivery. Unlike conventional intramuscular or subcutaneous application, MN-based vaccine application delivers vaccine directly into skin and this is known to be immunologically more relevant vaccination site than underlying tissue. Various fabrication methods have been used for microneedle fabrication such as LIGA, 2 Photon Polymerization (2PP), etc. followed by subsequent Micromolding. However, despite the number of advantages of these fabrication methods, the use of microneedles is limited till date due to lesser throughput. This paper focuses on methods used for the fabrication of microneedle and also explains the proposed method for polymer microneedle fabrication using Micromolding process. Proposed method for polymer microneedle fabrication includes preparing a master structure of microneedle array, then with the help of micromold made of suitable material; final microneedle array can be made of biocompatible, thermally curable material. The microneedle array will meet the structural requirements for painless drug delivery having small invasive surface area and will withstand the force required to pierce into the skin without tip breaking.