應用微流控光學矽晶片量測血糖濃度差別之研究

Abstract

本論文提出了利用擴散原理於微流控光學矽晶片上量測血糖濃度差別的方法。本論文研究了兩種擴散情形:單純擴散情形以及系統周圍外加水流(流動率10 ul/min)的擴散情形。此兩種情形皆經過COMSOL模擬和實際實驗比較。本實驗利用一含有四組微環共振腔的光學矽晶片做為量測工具。根據這些微環共振腔的分佈情形，實驗設計了微流管道與此矽晶片結合，以至於管道內流動的溶液可以通過這些微環共振腔，達到量測液體折射率變化的目的。本實驗所設計的微流管道包含一流動管道及一擴散管道，流動管道內可以控制流動的溶液濃度，擴散管道一端開口連接流動管道，其餘三端封閉，此情形可以確保在擴散管道內粒子的移動以擴散為主。在擴散管道內的微環共振腔偵測折射率的變化，達到觀察擴散管道內擴散情形的變化。實驗結果發現，單純擴散情形所得到的擴散常數8.8*10^(-10) m^2/s與文獻上的值9.4*10^(-10) m^2/s非常接近；而外加水流的擴散情形則比理論模擬結果快很多，此現象可用頂蓋驅動方腔流解釋之。

This thesis presents a glucose sensing method on a miniature optofluidic silicon chip based on the idea of diffusion. Two cases of diffusion, one without external flow and one with an external flow rate of 10 ul/min are analyzed both theoretically by COMSOL simulation and experimentally. The experiment utilized an silicon on insulator (SOI) chip containing 4 sets of microring resonators. The SOI chip was integrated with designed microfluidic channels, including a flow channel and a diffusion channel. A flow with glucose concentration was imported and exported through the flow channel. The diffusion channel was designed with three impermeable boundaries and one open boundary connected to the flow channel. In this case the glucose particles could penetrate through the diffusion channel only through diffusion. The microring resonators lied within the diffusion channel and detected the diffusion effect of the system. In the case without flow, the diffusion coefficient extracted from the experimental result is 8.8*10^(-10) m^2/s, which is close to the literature value 9.4*10^(-10) m^2/s. The diffusion speed obtained in the case with flow is higher than that in the theoretical simulation because of the driven convection in the lid-driven cavity.