本研究提出一個不需添加標定物質（Label-Free）的電化學式血紅蛋白（Hemoglobin）生物感測器，其在血紅蛋白濃度0.0001~1mg/ml, PBS的範圍內，可獲取快速的電化學還原電流嚮應訊號。吸附在碳紙電極上的血紅蛋白可利用微分脈衝伏安法（Differential pulse voltammetry）掃描獲得高靈敏度且低背景電流的偵測訊號。

實驗結果顯示，由於血紅蛋白捕捉結合氧氣的特性，促進了水中溶氧在碳紙電極上的還原反應，使其向正電位偏移。雖然感測系統中的血紅蛋白和肌紅蛋白（Myoglobin）還原峰不易分離，但來自肌紅蛋白的干擾可以經由在酸性環境中感測下最小化。再經過界面活性劑溶液浸泡改質的電極表面可以大幅降低肌紅蛋白的訊號，使得血紅蛋白和肌紅蛋白的訊號比值由0.79提高至80。而牛血清白蛋白（Bovine serum albumin）、溶菌酶（Lysozyme）在此電化學系統中沒有電化學訊號響應。經由電子顯微鏡影像中吸附血紅蛋白的分佈顯示，碳紙電極上的淺凹槽結構主導了血紅蛋白的吸附區域。

由於不需要額外添加具有電化學活性之反應媒子或螢光標誌，此感測系統提供一種可能用於體內in vivo感測血紅蛋白濃度的途徑。

A label-free electrochemical hemoglobin biosensor able to rapidly respond to a wide-range of analyte concentrations (0.0001 to 1 mg/ml in PBS) is presented. Hemoglobin adsorption on a carbon paper electrode is detected by exploiting the high sensitivity and low background current of differential pulse voltammetry.

The results indicate that oxygen reduction on the carbon electrodes is facilitated leading to a positive potential shift by the oxygen-binding property of hemoglobin. Although the reduction peaks caused by adsorption of hemoglobin and myoglobin are harder to separate, interference from myoglobin was able to be minimized by measuring in an acidic environment. And further modification of electrode surface by surfactants immersion can dramatically decrease the myoglobin signal, thus Hemoglobin /Myoglobin signal ratio increased from 0.79 to 80. The response of the electrodes when challenged with bovine serum albumin (BSA), lysozyme is also reported, with no current response to BSA or lysozyme being detected. The SEM images indicate the presence of micro structures comprising shallow notches on the carbon electrodes that lead to an unequal distribution of absorbed proteins.

Since there are no electrical active probes or fluorescence-labeling chemicals involved, this platform offers a potentially safer route to in vivo hemoglobin measurement.

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