Microneedle Manufacturing and Testing

Progress in Microneedle-Mediated Protein Delivery

“…Since silica glass is brittle and not absorbable, like silicon, it can be used only for experimental purposes, not for commercial usage [51]. Some types of ceramics, such as alumina (Al 2 O 3 ), calcium sulfate dehydrate, calcium phosphate dehydrate, and Ormocer can be used to manufacture MNs [52,53]. Carbohydrates such as maltose, sucrose, and trehalose can be used as a matrix of MNs [54,55].…”

Engineering Microneedles for Therapy and Diagnosis: A Survey

“…A relatively high Young's modulus enables glass-based MNs to pierce the derma without deformation [57]. The chemical inertness of glass makes glass-based MNs safe in medical applications [38]. The low cost and simple fabrication method of glass-based MNs has drawn much consideration.…”

“…However, glass is also brittle, which is dangerous. Additionally, its chemical inertness excludes it from almost all chemical fabricating methods, so glass-based MNs are still fabricated by the traditional micropipette pulling way [38]. The method can only handle one MN at a time, which cannot achieve a complex structure and needs manual operations.…”

“…Common fabrication approaches of carbohydrates-based MNs are micromolding and drawing lithography. Carbohydrate materials are usually used to fabricate dissolving MNs for drug delivery [38]. The carbohydrate-based MNs are able to pierce the stratum corneum owing to their relatively strong mechanical strength after solidification.…”