目前雖然市面上有許多藥物貼片，但是因為我們表皮層的最外層被角質層所覆蓋，這是人體很重要的保護屏障，但也成為藥物滲透皮膚時最大的障礙。所以利用微機電製程技術製作出生物可分解微針狀陣列結構應用於藥物貼片上，改善上述所提出藥物滲透問題及控制多方面的藥物釋放問題。
本研究提出了一種架構為兩層式微針狀陣列貼片，我們利用聚乳酸(PLA)材料當作第一層架構，可增加微針頭穿刺進入表皮內之能力而進行藥物釋放，此外，之前研究證實PLA具有抑制“ initial burst”現象，有抑制藥物快速釋放導致藥物毒性過高或過敏的現象。第二層架構利用聚甘醇酸共聚物(PLGA)當作第二層包覆藥物的材料，因為PLGA可提供長時間的藥物釋放所以我們選擇適當比例PLGA來控制藥物釋放速率。因此本研究將針對聚乳酸微針貼片經皮性藥物輸送胰島素等之臨床醫療可行性研究。

The characteristics of some drugs are not easy to be efficiently used in human body due to molecular weight, permeability, dissolution and etc. The nano-technology approach could improve the problem to enhance the capability in drug delivery for the target organ. We attempt to employ the nano-carriers to take the drugs into the blood circulation and remedy illness. We will develop the delivery capsule for transdermal drugs by MEMS fabrication to miniaturize the scale for painless remedy and evaluate the drug release through derma as well. The transdermal drugs are designed to patients for a long-term and consistent therapy.

The new framework purposed in this paper composed of two layers. We employed PLA firstly as the needle material, which provides not only a tougher mechanical property to contribute a stronger fracture force, but also an outer shell to prevent the “initial burst” problem of the second layer. The second layer was made from appropriate blends of PLGA and drugs to furnish sufficient medical dose rate. We will to assessment the capability of insulin in transdermal delivery by PLA/PLGA polymer micro needles patch.

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