Parylene Electrothermal MEMS Drug Delivery Valve

論文發表人：李柏穎 (南加州大學電機所博士班)

 

http://www.acs.org/

 

我們提出一個用於供藥之電熱驅動, 拋棄式, 低功率C型對聚二甲苯微機電閥.  這個常關閥是的一個微噴注幫浦的一部份可用於快速供給輻射染劑進入動物血液循環系統.  這個低功率超輕重量的閥實現腦神經顯影術於自由活動且無束綁的動物.  在此我們說明此裝置的設計與製造的方法.  這個閥包含安裝在兩個導管間的一個對聚二甲苯/白金/對聚二甲苯的複合薄膜且由微機電系統技術所製造.  我們也在實驗室對此閥的功能進行測試.  白金薄膜的電阻率溫度常數也經過校正且得到其對電流之熱反應.  電流會導致閥的薄膜鎔化進而打開流通孔道.  測試結果顯示本裝置消耗約25至50微瓦的功率且電流約在7到20 微安培間.  最後, 我們將測試完畢的閥裝置與微噴注幫浦組合完成系統整合並討論結果.

 

We present an electrothermally-activated disposable, low-power Parylene C MEMS valve for drug delivery.  The normally-closed valve is part of a microbolus infusion pump used for rapid delivery of a radiotracer into the circulation.  This low-power, light-weight valve enables neuroimaging of brain blood flow in freely-moving untethered animals.  The design and fabrication method are presented.  The valve consists of a Parylene C/Pt/Parylene C membrane mounted in a catheter and was fabricated using microelectromechanical systems technology.  Valve performance was characterized in benchtop experiments.  The temperature coefficient of resistivity of the Pt thin film was calibrated and the thermal response to applied current was obtained.  Current application induces thermal degradation of the valve membrane to create a fluid flow path.  Opening powers of 25-50 mW were obtained for operating currents of 7-20mA.  Finally, the assembly technique to incorporate the valve in to the microbolus infusion pump is described.