微針是一種新型的經皮無痛給藥方式，可以解決傳統藥物傳輸上的多種不便，例如消化系統造成的藥物代謝，或是皮下注射時會造成過量藥物進入血液造成副作用等。把藥物裝載、塗佈在微針內外可有效突破角質層之障礙，且在患部給藥時，更可以有效控制藥量。
本研究用高生物相容性的透明質酸製作可溶解式微針貼片，並包覆Minoxdil此種具生髮療效之外用藥，用於治療雄性禿其常見的遺傳性疾病，並期望可改善目前相關市售商品存在的問題。例如微針可利用物理性的方式突破角質層的屏障，便可取代原本配方內會造成病患皮膚紅腫的皮膚促進劑丙二醇，也可以有效增進藥物傳輸效率。
本研究設計一種二段式製程，可以控制針體內包覆的藥量，也可減少藥物在製程中的浪費，溫和的製作環境也能保持藥物的活性，且經由機械強度測試及體外實驗證實該微針兼具可溶解性和足夠穿刺角質層的機械強度。並經藥物釋放實驗和動物實驗得知含藥微針在給藥效率上遠大於傳統給藥方式。總體而言，本研究的微針貼片是具有應用潛力的給藥模式。
關鍵字：可溶解式微針、雄性禿、米爾地諾、經皮傳輸系統

Microneedle patch is a painless transdermal drug delivery method, It could solve some problems in traditional drug delivery such as digestive system causing drug metabolism and subcutaneous injection causing some side effects. Coating drug on or loading drug in microneedle can carry active ingredient through stratum corneum, also can contol dose well when microneedle patch apply on localized topical area.
We used hyaluronic acid to fabricate dissolvable microneedle patch and encapsulated minoxidil into microneedles. Minoxdil is a drug for exterior use that can be used to treat androgenetic alopecia, but related commercial products have some shortcomings, for example, propylene glycol which is used to soften stratum corneum cause skin allergic reaction, comparing chemical promotion, microneedle patch provide physical way to make drugs through nature barrier of skin.
In this research, we designed a two-step process to fabricate microneedle patch, that can effectively reduce drug waste. And gentle production process used could maintain drug activity well. We also do in-vitro test on cadaver skins to make sure patch has enough mechanical strength to penetrate stratum corneum. In the release test and animal test, we found microneedle patch has higher delivery efficiency than tradition way.
In this study, we may conclude that germinal MNs patch has potential to commercialization.
Keywords ─ dissolving microneedles; Androgenetic alopecia; minoxidil transdermal drug delivery

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