近年來，經皮藥物輸送成為相當受人矚目的給藥方式，此方法具有以下優勢:可以使藥物無須經過腸胃道的消化分解以及肝臟的初步分解，維持藥物品質，非侵入式的藥物傳送可降低感染風險，其使用方便，給藥次數低，可提高患者的配合度。在各種不同經皮藥物貼片的方法中，可溶性高分子微針的特色及優勢在於其具有生物相容性，不會因肌肉收縮而有像金屬微針斷裂破碎的情況，提供足夠的機械強度及安全性，並可選擇不同的高分子控制藥物釋放的速率。本研究是藉由微過濾的方式製作可溶性的高分子微針貼片，我們做出具有類似金字塔狀微結構陣列之PDMS模具，將模具放在濾紙上，並滴上聚乙烯吡咯烷酮(PVP)之高分子溶液，開始真空抽氣，探討影響微針成形的因素，包括濾紙孔徑大小、高分子濃度、抽氣時間及分子量大小，並討論高分子堆積的高度對於微過濾的時間所成的線性關係；也觀察高分子微針在組成豬皮成分的明膠固化物中，其溶解形貌與濃度之變化，套入質傳方程式找出其理論之數值，進行討論，以及測試高分子微針在豬皮穿刺中之深度與微針之機械強度。實驗結果顯示，我們能在一小時內做出高分子微針貼片，微針成形堆積的高度符合濾餅過濾的機制，而使用抽氣過濾法製備出的微針和一般方法所製備的微針機械強度無異。

In this study, we proposed and demonstrated that the dissolvable and flexible polymer MNs patch can be fabricated by microfiltration. The polydimethylsiloxane (PDMS) mold with funnel-like cavities was first created, which was placed on top of a filter paper. A droplet of polyvinylpyrrolidone (PVP) solution was dispensed on the mold, followed by applying vacuum. Different parameters such as solution concentrations, filtration time, molecular weight of the polymer, pore size of the membrane were discussed. It was found that PVP microneedles can be fabricated by filtration method within 1 hr. In addition, the MNs as fabricated have sufficient mechanical strength to penetrate the porcine skin with the penetration depth around 250 µm. Dissolution of the PVP microneedles in 10 wt% gelatin was also monitored and the distribution of R6G inside gelatin can be described by Fick’s 2nd law.

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