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Generally speaking,drugs can be delivered into human body through different routes of administration,among which injection and oral delivery are the most commonly used.However,injection cannot be easily conducted by patients themselves because it requires trained personnel and may introduce pain during injection step.Oral delivery sometimes is not effective as the pharmacological action of medicines could be affected by internal digestion system,thus protein and DNA drugs have a poor absorption rate.To overcomethese drawbacks,transdermal drug delivery through microelectromechanical systems (MEMS) based microneedles has drawn much attention recently.In order to penetrate the skins outmost layer (i.e.stratum corneum,SC) for effective application of drug delivery approaches,microneedles made of various materials have been investigated.Although microneedles can be fabricated into sharp shape for easier penetration,such microneedles are prone to be damaged during the insertion process due to their frangibility.Moreover,most of them have unproven biocompatibility.The SU-8 microneedle,as a kind of biocompatible and inexpensive polymer-based device,is proposed as suitable material in this paper.Here,we will demonstrate a new method to fabricate SU-8 microneedles.Biocompatible SU-8 mictoubes are fabricated by photolithography technology (Fig.1).PET film is deployed to release the large area SU-8 microtubes.In order to overcome the impermeable barrier of SC layer,biodissolvable maltose tips were integrated on the SU-8 microtubes by drawing lithography technology (Fig.2).Shape maltose tips (Fig.3) will lead the SU-8 microneedles easily pass through the SC layer of the skin (Fig.4).Subsequently,maltose tips will be dissolved in the body fluid within a few minutes and drugs can be delivered throughthe SU-8 microneedles (Fig.5).