微流體乳化晶片廣泛應用於石油、化妝品、生醫以及製藥等領域，並具有傳統乳化方式所沒有的優點，本研究將沿用本研究團隊在過去開發的雙重乳化微流體晶片，透過調整注射幫浦控制流道入口的各相流率參數，以改變液珠生成的尺寸及孔洞的疏密程度，以製備不同結構的藥物微球。固定第一階段總流率(Qt,1)改變第一階段連續相以及分散相流率比(R1)以及外部水相流率(Qo)製作多種孔隙率以及多種幾何尺寸的PLGA藥物微球，實驗結果發現R1越小其孔洞程度越密集，Qo越大藥物微球尺寸越小。非多孔結構以及R1=3所製作出來的PLGA藥物微球其藥物包覆率(E.E.)及載藥率(L.C.)值不會隨著Qo的改變而有明顯改變，但R1=5及R1=7所製作出來的PLGA藥物微球其E.E.及L.C.值會隨著Qo的升高而逐漸下降。以恆溫培養箱以及迴轉震盪器模擬生物體內環境，進行藥物釋放實驗，較大尺寸的PLGA藥物微球有更高的初始藥物釋放，而由R1=3及R1=7所製作出來的藥物微球中，無論其藥物微球尺寸大小，R1=3所製作出來的藥物微球之初始釋放速率始終大於R1=7所製作出來的藥物微球，因R1=5所製作出來的藥物微球因內外部相連通的孔洞結構以及相較R1=3所製作出來的藥物微球來的稀疏的孔洞密度，使自催化作用具有相對高的影響，因此R1=5所製作出來的藥物微球其釋放曲線具有初始釋放速率不隨著藥物微球尺寸改變而改變的特性。本研究成功製作出多種不同結構的藥物微球，並具有廣泛的藥物釋放特性，未來在藥物載體或藥物釋放的實驗中，可利用微流體裝置製作少量且精確的藥物微球以進行實驗，以大幅減少實驗成本。

In this research, the double emulsion microfluidic chip was used to make the porous PLGA microspheres. The PLGA microspheres with multiple porosities and multiple sizes was fabricated by operation parameters, which includes the 1st flow rate ratio (R1) and external water phase flow rate (Qo). The experimental results showed that the Porosity of PLGA microsphere increases as R1 decreases; the size of PGLA microsphere decreases as Qo increases. The drug entrapment efficiency (E.E.) and drug loading capacity (L.C.) of non-porous PLGA microsphere (R1=∞) and porous PLGA microspheres made by R1 = 3 do not change significantly with the change of Qo. The E.E. and L.C. of the porous PLGA microspheres made by R1 = 5 and R1 = 7 decrease with the increase of Qo. Use a constant temperature incubator and a rotary oscillator to simulate the biological environment for drug release experiments. The results verified that larger PLGA microspheres have higher initial drug release rate even with porous structure. Regardless of the size of the porous PLGA microspheres made by R1=3 and R1=7, the initial release rate of the porous PLGA microspheres made by R1=3 is always higher than that of the porous PLGA microspheres made by R1=7. The porous PLGA microspheres made by R1=5 initial release rate does not depend on the size of the PLGA microspheres. In the future, the presented microfluidic devices and the fabrication process can be used to make small quantities of precise PLGA microsphere for clinical or pharmaceutical test.

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