嗜鹽菌Halobacterium salinarum紫色細胞膜(purple membrane, PM)中含有光驅動質子幫浦細菌視紫質（bacteriorhodopsin, BR）蛋白。BR受光激發後，會產生一連串光循環反應及單一方向跨膜質子梯度，可用以產生光電響應。本研究藉由分析PM晶片在不同pH值、鹽濃度與溫度之溶液中的光電流值變化，探討其穩定性。首先單以氧化avidin為架橋並固定化b-PM之PM晶片，探討以與固定化b-PM相同組成的緩衝液做為量測電解液時之晶片光電流變化。結果發現用以塗覆b-PM之電解液中不含鹽時，在pH 8時可產生最大的光電流值，且光電流在pH 7到pH 8.5間極性反向，以AFM分析圖及光電流圖可估算每片PM所產生的光電流值，且在緩衝液為pH 6.5時有最大值。其次懸浮液和電解液溶液中添加10 mM KCl的時，則在pH 8時可產生最大光電流值，光電流在pH 7到pH 8.5間極性反向，其原因為溶液中的鹽離子可中和PM表面電性，使PM塗覆量增加，但當pH值太高時會使鹽離子對PM膜表面效應降低，而以AFM分析圖及光電流圖所估算每片PM所產生的光電流值，則在緩衝液為pH 9時有最大值。其次對於以氧化avidin與氧化石墨稀複合物為架橋，而固定化修飾有biotin的b-PM後所得的PM晶片，置於微流道中進行即時光電流檢測，並探討不同溫度與不同流速的電解液對及時量測光電流之影響。晶片不加熱而僅加熱電解液時，在不流動時，晶片光電流在高溫時下降比例最高，但在增加流速後，光電流下降程度會減少。而使用同步加熱晶片與電解液時，也有相同情況發生，推測是因為升高流速後可增加電解液的替換率，降低受光BR所推出之質子，降低電解液pH而降低光電流之程度。

Bacteriorhodopsin (BR) residing in the purple membrane (PM) of Halobacterium salinarum is a light-driven proton pump protein. When BR is excited by light, it undergoes a photocycle to directly transport a proton through the membrane, generating a proton gradient across PM, which can be converted to a photoelectrochemical potential. In this study, we investigated the effects of pH, salt concentrations, as well as electrolyte temperatures and flow rates on the photocurrent density and the stability of the PM-coated chips. First, the pH and salt effects were studied with b-PM, a PM form modified with biotin, immobilized on solid substrates with oxidized avidin as the linker. The buffer used to suspend b-PM for coating was the same as the electrolyte used for photocurrent measurements. As a result, the maximum of total photocurrent densities was obtained when the buffer contained no salt and at pH 8. The reversal of photocurrents was observed between pH 7 and 8.5. By coupling both AFM and photocurrent analyses, we estimated the photocurrent density produced by each illuminated b-PM sheet. The maximum value with the desalinated buffers was observed at pH 6.5. On the other hand, for the buffers containing 10 mM KCl, the maximum photocurrent density per illuminated b-PM sheet was obtained at pH 9 and the photocurrent reversal was observed also between pH 7 and 8.5. Next, in order to investigate the effects of electrolyte temperatures and flow rates on the photocurrents of b-PM coated chips, the chips were mounted inside a microfluidic device. In this experiment, b-PM was immobilized with an oxidized avidin-graphene oxide complex as the linker and the buffer flowing over the chip was also used as the electrolyte for real-time photocurrent measurements. As a result, we found that increasing the flow rate of the electrolyte mitigated the reduction of photocurrent densities caused by temperature elevation.

余安棣，製備具高度方向性之Bacteriorhodopsin生物電晶片，國立台灣科技大學化學工程研究所碩士論文，2009
陳逸航，定向性細菌視紫質晶片之光電與二倍頻響應探討，國立台灣科技大學化學工程研究所碩士論文，2010
蔡孟訓，自排性單層分子膜於Bacteriorhodopsin光電晶片製備之探討，國立台灣科技大學化學工程研究所碩士論文，2011
林其融，AFM探討分別以結合氧化石墨烯之親和吸附與共價鍵結作用固定化之紫膜，國立台灣科技大學化學工程研究所碩士論文，2012
吳欣穎，細菌視紫質泛用型免疫光電晶片製備與原子力顯微鏡分析，國立台灣科技大學化學工程研究所碩士論文，2015
陳冠辰，適體－細菌視紫質生物光電感測晶片之探討，國立台灣科技大學化學工程研究所碩士論文，2015

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