Back to Journals » International Journal of Nanomedicine » Volume 7

A scalable fabrication process of polymer microneedles

Authors Sixing Yang, Yan Feng, Lijun Zhang, Nixiang Chen, Yuan W, Tuo Jin

Received 23 November 2011

Accepted for publication 15 December 2011

Published 12 March 2012 Volume 2012:7 Pages 1415—1422


Review by Single anonymous peer review

Peer reviewer comments 4

Sixing Yang, Yan Feng, Lijun Zhang, Nixiang Chen, Weien Yuan, Tuo Jin

School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China

Abstract: While polymer microneedles may easily be fabricated by casting a solution in a mold, either centrifugation or vacuumizing is needed to pull the viscous polymer solution into the microholes of the mold. We report a novel process to fabricate polymer microneedles with a one-sided vacuum using a ceramic mold that is breathable but water impermeable. A polymer solution containing polyvinyl alcohol and polysaccharide was cast in a ceramic mold and then pulled into the microholes by a vacuum applied to the opposite side of the mold. After cross-linking and solidification through freeze-thawing, the microneedle patch was detached from the mold and transferred with a specially designed instrument for the drying process, during which the patch shrank evenly to form an array of regular and uniform needles without deformation. Moreover, the shrinkage of the patches helped to reduce the needles' size to ease microfabrication of the male mold. The dried microneedle patches were finally punched to the desired sizes to achieve various properties, including sufficient strength to penetrate skin, microneedles-absorbed water-swelling ratios, and drug-release kinetics. The results showed that the microneedles were strong enough to penetrate pigskin and that their performance was satisfactory in terms of swelling and drug release.

Keywords: polymer microneedles, ceramic mold, polyvinyl alcohol, swelling

Creative Commons License © 2012 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.