整合奈米流道預濃縮器與粒子分離技術用於粒子操作晶片

Abstract

本研究成功結合預濃縮機制(preconcentration mechanism)以及分離技術，將兩種步驟整合在一起，利用微影製程做出微米流道和Nafion作為離子選擇性薄膜(ion-selective membrane)，將上述兩者整合而成本實驗之檢測晶片，其中微米流道分為兩條，其一為濃縮流道(concentration channel)、其二為緩衝流道(buffer channel)而Nafion則橫跨兩流道。 預濃縮機制為施加一電位差於Nafion兩端，可產生濃度極化效應(ion concentration polarization, ICP)，意即一端為離子富集區(ion enrichment region)、另一端為離子空乏區(ion depletion region)，爾後在空乏區一側施加偏壓便可利用第二種電滲透流(electroosmosis of the second kind)使空乏區之高電壓側產生濃縮區塊(preconcentration plug)。 分離機制是藉由電泳(Electrophoresis)帶動，不同帶電量的螢光小球會有不同的速度，以及在突縮突擴流道中流場及電場造成的速度差，將不同粒徑的螢光小球進行分離。

In this thesis, we have successfully integrated preconcentration mechanism and electrophersis separation. Fabricate a detection chip by coupling microchannels which including two channels: concentration channel and buffer channel, and Nafion as ion selection membrane which crossing two channels. Preconcentration mechanism is applying a voltage drop in Nafion ends at first, can produce ion concentration polarization (ICP) which refers to one of the end becomes ion enrichment and the other becomes ion depletion. Then we apply a bias voltage to generate electroosmosis of the second kind to aggregate the preconcentration plug near the ion depletion region on the high voltage side. The separation system is applying electrophoresis technique to make particles which have different net charge moving in different velocity. The particle velocity in flow field and electric field is affected by sudden contraction flow channel. Different size particles have different net charge. We can make different size particle separated in different velocity.