本研究目的為開發一Y字型分岔微流道，使其能快速均勻的分佈檢體及減少檢體損失，未來可應用於高通量晶片中之均勻濃度分佈，或是和微量注射器結合成為實驗室中檢體分佈之微型工具。
檢體分流的均勻度和流道幾何設計息息相關，因此在研究過程中，透過數值模擬分析，觀察在不同幾何設計中檢體內部壓力的分佈及變化，進而找出優化的流道幾何尺寸，作為實驗的晶片物理尺寸。判斷分岔微流道幾何尺寸優劣的定義在於檢體於分流過程中的最大與最小壓力差，當此壓力差較小時，代表檢體通過此分岔微流道時的速度場較均勻，較能達到均勻的分佈且減少檢體於分流過程中損失。經過多次的模擬分析，將代號[Y-R2.0H0.5]的分岔微流道物理尺寸利用微铣削機及熱黏合加工完成，作為實驗的晶片，以驗證模擬的結果。
經過五十次的實驗及分析，得到檢體在此[Y-R2.0H0.5]的晶片上可達到2.13%的均勻度，而檢體損失率為5%。此結果與之前發展的T字型分岔微流道相比，在均勻度上提升了1.7%，而檢體損失率降低了3%。為了提高本實驗結果之可信度，我們利用單因子變異數分析實驗數據，得到了90%的信心程度，證明本研究發展的Y字型分岔微流道效果比T字型分岔微流道優良。

A Y-bifurcation microchannel used for uniform reagent distribution and minimized reagent loss was developed in this study, which can be integrated with a high throughput system and precisely distribute the reagent concentration. Numerical simulations were used to estimate the geometry-dependent pressure distribution inside the reagent plug during the fission process, and the results were taken as a reference when modifying the design of this Y-bifurcation microchannel. To optimize the performance, four different geometries of the Y-bifurcation microchannels were designed and tested, and a Y-bifurcation microchannel with a 2 mm radius round corner and a 0.5 mm height separator was found to exhibit smallest pressure difference inside the split reagent plug and used for subsequent experiments. The optimized Y-bifurcation microchannel was manufactured on the PMMA substrates with a micromilling machine and hot embossing technique. Fifty experiments were realized on this Y-bifurcation microchannel: the results demonstrated that the average reagent distribution uniformity is 2.13% with a STD of 3.94% and the average residual reagent volume is 95% with a STD of 4.3%. One-way ANOVA was applied to further confirm that this Y-bifurcation microchannel can achieve better performance than the previous T-bifurcation microchannel with a 90% confidence level.

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