氮化矽微米孔隙元件於細胞濃度快速鑑別研究

Abstract

本研究利用微米孔洞陣列氮化矽薄膜作為細胞濃度偵測之元件。量測通過微米孔洞的導電度以分析檢體中粒子的濃度。首先，利用微米製作技術製備出氮化矽微米孔洞陣列薄膜，孔洞數分別為9、49、100、484。經由電路模型的建立分析以及實際量測結果，決定後續實驗中施加電壓的操作頻率。實驗過程中，檢體以固定流速，20 µl/min 的流速進入流道中，電壓由鎖相放大器經由氯化銀參考電極供給並且同時量測電流值變化，操作條件為10 mV，頻率10 Hz。本實驗分別量測了聚苯乙烯粒子以及子宮頸癌細胞的濃度。實驗過程中，以不同孔洞數量的元件量測檢體中粒子濃度，並且比較其結果。結果顯示，擁有孔洞數為49的元件於兩分鐘可達到最佳的濃度鑑別能力，其對於聚苯乙烯粒子以及子宮頸癌細胞的濃度鑑別範圍為102/ml to 106/ml。另外，在此量測系統中，所需要的量測時間不到兩分鐘，本研究成功的提出了可以快速量測粒子濃度的系統。

In this research, silicon nitride micropore sieve was prepared and applied to resolve bead and cell concentrations via the measurement of the conductance across the pore. The micropore sieve was fabricated via microfabrication processes on the free standing silicon nitride membrane with the pore number ranging from 9 to 484. Electrical equivalent circuit model of the micropore sieve device was constructed and compared with the measurement data. Analytes were flowed through the micropores at a flow rate of 20 µl min-1 via a syringe pump. The AC sine-wave voltage (10 mV rms) at 10 Hz was applied between two Ag/AgCl electrodes across the micropores by a lock-in amplifier, and the ionic current was analyzed. Polystyrene beads and HeLa cells concentrations were characterized separately. Devices with different pore number were optimized and applied to resolve the beads/HeLa cells concentration. In 2 minutes, the device with 49 micropores exhibited the best resolving ability for polystyrene bead and HeLa cells concentration ranging from 102/ml to 106/ml.