在藥物使用的範疇中，如果想要使藥品能夠完全的發揮出療效，藥物的控制與釋放一向是研究的重點，而藥物載體的粒徑大小與藥物釋放之效果息息相關，隨著微機電製程技術的進步，藥物載體的粒徑大小越做越小，過去縮小粒徑的方式不外乎改變管道幾何形狀、縮小管道尺寸與改變流體特性，而能製備出最小粒徑大約為20 m。本研究將過去被用於質譜儀分析之電噴灑現象，運用在製備聚乳酸-聚甘醇酸共聚合物(Poly(lactide-co-glycolides), PLGA)藥物載體，並改變連續相乳化劑之濃度，使PLGA藥物載體粒徑縮小至5 m以下。本研究利用微機電製程與灌注成形法製作聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)微流道晶片，利用管道之幾何形狀造成鞘流現象，使製備之PLGA乳化球粒徑均一，同樣藉由微機電製程技術在ITO玻璃基板上製作所需之電極晶片，並與微流道晶片接合，目的為提供電場於微流道之鞘流區，使鞘流現象與電噴灑現象結合，達到晶片實驗室之目的，操控連續相乳化劑之濃度與施加之電壓，製備之藥物載體粒徑範圍從最大70 m到最小2 m，並在添加乳化劑Span 80濃度3% (w/w)施加電壓5000 V時製備出PLGA纖維絲，纖維絲直徑從最大18 m到最小7 m，此尺寸之改良對於藥物載體之療效與纖維絲之應用將更為廣泛。

Controlling and releasing drugs play an important role to display curative effects in the drug utilization category. There is strong correlation between drug carrier size controlled and drug-released. Nowadays, the size of drug carrier become more and more small by improving Micro Electro Mechanical Systems (MEMS) technology, which used different geometry shape channel, shrunk channel size or changed flow capability, and only could get particles which minimum sizes are around 20 m.
The aim in this study is using electrospray of mass spectrometry analysis to fabricate submicron size Poly (lactide-co-glycolides) (PLGA) drug carriers by controlling different concentration of continual phase emulsifier.
This study uses MEMS process and casting molding to manual Polydimethylsiloxane (PDMS) microchannel chips and fabricates uniform size PLGA emulsion particles by flow focusing, which is made by designing geometry shape microfludic chips. In addition, this study uses MEMS technology to fabricate electrodes on ITO glass substrates and combine with mircofludic chip for applying electric field in flow focusing area. Combining flow focusing phenomenon and electrospray phenomenon could control different concentration continual phase emulsifier and apply voltage, so that PLGA drug carriers, which are less than 2 m, and PLGA fibers ,which are thinnest 7 m, could be fabricated. These actions will promote effects of drug carriers; furthermore, drug carriers could be used extensively.

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