以網版印刷碳電極製作類克拉克式溶氧感測器的研發

Clark-Like Dissolved Oxygen Sensors Based on the Screen Printed Carbon Electrodes

林孝安(Shiau-An Lin) ； 吳靖宙(Ching-Chou Wu)

《農林學報》 60卷3期 (2011/09) Pp. 217-229

https://doi.org/10.30089/JAF.201109.0004

摘要

在發酵工業製程上，可藉由微生物生長條件的最適化，以達到生物反應器的最佳產率。特別對嗜氧性微生物而言，溶氧濃度的改變會顯著影響微生物代謝產物的形成，因此開發可長期、穩定、價格便宜與專一的溶氧感測器是項重要的議題。本研究以電沈積金奈米層之網版印刷碳電極（screen printed carbon electrode，SPCE）當工作電極，並塗佈聚二甲基矽氧烷（polydimethylsiloxane，PDMS）乳膠在SPCE上，以形成類克拉克溶氧電極。此電極經2-[methoxy(polyethylenxy)-propyl]trimethoxysilane（PEG-silane）修飾後，可顯著抑制白蛋白對PDMS 透氧膜的毒化，然而經PEG-silane修飾後的電極其90％響應時間從35.6 s增加至40.7 s，此電極在0.09-4.75 ppm氧濃度呈現一良好線性關係（R^2＝0.9935）。在長期穩定度的測試中，發現先經三天浸泡處理的時間，可使PDMS膜的氧氣通透率趨於穩定。在一天一次的間斷式量測下，經30天後其電流值僅下降至初始值的88.39±2.28%。此電極的開發可大幅降低現有之克拉克式溶氧電極的製作成本與程序，並具有至少30天的使用壽命，此結果顯示此電極具有可應用於生物反應器內進行氧氣消耗監測的潛力。

關鍵字

電沉積金奈米層 ； 網版印刷碳電極 ； 類克拉克溶氧感測器

並列摘要

In the fermentation industries, the bioreactor can achieve the best product yield by optimizing the growth conditions of microorganisms. Especially for aerobic bacteria, the change in the dissolved oxygen concentration may significantly influence the product formation of microorganisms. Therefore, it is an important issue to develop a long-term, stable, cost-effective and specific oxygen sensor. In this study, an Au nanolayer-electrodeposited screen printed carbon electrode (SPCE) acted as the working electrode was coated by the polydimethylsiloxane (PDMS) emulsion to form a Clark-like dissolved oxygen sensor. The modification of 2-[methoxy(polyethylenxy)-ropyl] trimethoxysilane (PEG-silane) can reduce the poisoning of albumin to the PDMS surface of SPCE but let the 90% response time increase from 35.6 s to 40.7 s. Moreover, the electrodes can obtain a good linearity (R^2＝0.9935) in the range of 0.09-4.75 ppm. After three-day soaking in phosphate buffer solution, the oxygen permeability of PDMS membrane could present stable. After measuring for 30 days, the current discontinuously measured once one day only decreased to 88.39±2.28% of the original value. The results show that the electrodes can drastically reduce the fabricating cost and procedures compared to the presently used Clark oxygen electrode, and possess at least 30 day life time. The Clark-like electrodes have a great potential capable of being used in a bioreactor for the monitoring of oxygen consumption.

並列關鍵字

Screen printed carbon electrodes ； Clark-like dissolved oxygen sensors ； Au-electrodeposited nanolayer