電壓誘導溶血應用於血糖量測系統之血球容積比誤差補償校正

Glucose Monitoring System with Hematocrit Error Compensation Based on Voltage-Induced Hemolysis

翁志偉(Chih-Wei Weng)

指導教授 ： 鄭宗記

國立臺灣大學/生物資源暨農學院/生物產業機電工程學研究所/博士(2017年)

https://doi.org/10.6342/NTU201702178

摘要

血球容積比(Hematocrit，Hct)為一種手術和臨床診斷的關鍵判定參數，於全血領域的生物感測器上，也會高度影響血液分析裝置的分析結果。因此，本研究在網印碳電極（Screen-Printed Carbon Electrode，SPCE）的基礎上開發了一種準確且快速的Hct測定方法，藉由此新發展的檢測技術，量測系統無需新增額外的設備或量測平台，只要調整輸出的電位及建構相對應的演算法，即可將Hct對於生物感測器的干擾排除，將來還可以應用於各種全血量測的拋棄式電化學感測系統上。首先在Hct量測的研究開發上，採用電壓誘發溶血的方式，在鐵氰化物塗覆的電極上施加3.0V的直流電壓，造成電極表面的血球破裂並釋放血紅蛋白，血紅蛋白自發性地將鐵氰化物還原為亞鐵氰化物，再藉由電極氧化亞鐵氰化物獲得氧化電流量來估算Hct。線性掃描伏安法，可以在5s內測定10%至70％的Hct（r2 = 0.9907），若採用計時電流安培法於電壓在3.0 V的條件下，即可在0.8s 內完成Hct量測（r2 = 0.9833）。
更進一步，結合上述Hct的檢測方式，導入應用於一次性葡萄糖感測器的開發可以獲得準確和快速的血糖數值。這項研究的目的是開發一種補償Hct的方法，提高葡萄糖計算的準確度，使Hct對葡萄糖量測的干擾極小化。傳統上量測葡萄糖濃度的量測平均偏差與Hct呈線性相關，從Hct 9％到Hct 70％，對應的量測偏差分別從40％變化到-50％，所以，單一電壓的計時電流安培法量測葡萄糖濃度具有很高的Hct依賴性（R2 = 0.992）。本研究結果發現，3.2V的額外一組電位不僅可用於Hct檢測，而且還可用於補償Hct所造成的葡萄糖量測干擾，導入此補償邏輯後，葡萄糖量測的偏差(Bias)不再受Hct這個參數影響（R2 = 0.0705），並能夠在Hct 10％〜70％的範圍內進行量測，量測偏差控制在±10％內，此結果與傳統的計時電流法相比，大大的提高了全血葡萄糖量測的準確度。

關鍵字

血液容積比 ； 溶血反應 ； 網印碳電極 ； 可拋棄式 ； 血糖

並列摘要

Besides a crucial parameter for surgery and clinical diagnosis, hematocrit tends to affect the analytical result of point-of-care analytical devices. Therefore, an accurate and quick method for measuring hematocrit was developed on the basis of screen-printed carbon electrodes (SPCE). An impulse of 3.0V DC voltage was imposed on ferricyanide-coated SPCE to induce hemolysis, the released hemoglobin reduced the ferricyanide and generated a higher oxidation current for estimating hematocrit. Hematocrit ranging from 10 to 70% can be determined in 5s by linear sweep voltammetry (r2= 0.9907) or 0.8s by 3V of potential step voltammetry (r2 = 0.9833).
Furthermore, accurate and quick disposable sensor for both glucose and hematocrit (Hct) was also developed. The aim of this study was to develop a method for glucose calculation with improved accuracy using the Hct compensation method that minimizes the effects of Hct on glucose measurements. Typically, simple chronoamperometry with one potential step is used to measure glucose concentrations. The mean biases of glucose measurements were linearly correlated with Hcts from 9% to 70% and the deviations ranged from 40% to -50%. The result indicated that simple chronoamperometry method for glucose measurements were highly Hct dependent (R2 = 0.992). The present study showed that an additional potential step of 3.2V not only can be used for Hct detection but also applied for interference compensation of glucose measurement. After compensation, the biases of glucose measurements of proposed method were Hct independent (R2 = 0.0705) and is consequently capable of operating acceptably in a wide Hct range of 10% ~ 70% with biases in ± 10% which has improved the accuracy of glucose measurements as compared with the existing chronoamperometry method.

並列關鍵字

Hematocrit ； Screen printed carbon electrodes (SPCE) ； disposable ； glucose sensor

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