應用版式電極製作可攜式快速尿酸感測裝置

Applied screen-printed carbon electrode to make a portable and rapid-response uric acid sensing device

徐俊傑(Chun-Chieh Hsu)

指導教授 ： 王士豪 ； 廖峻德

中原大學/工學院/醫學工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300050

摘要

本研究是利用酵素能夠藉由氧化還原作用以識別特定分子的基本特性，使用尿酸酶做為感測器系統之生物電化學反應的感測元件，再將輸出的微小電流轉換為電壓並呈現一電訊號。首先求得配置不同的尿酸濃度與其電訊號的差異表現之關係，再利用電壓與時間的特性圖，以End-point measurement、Quasi-Kinetic measurement I、以及Quasi-Kinetic measurement II之三種不同的計算模式，藉以判讀尿酸的濃度，並可將特定的計算模式內建於尿酸感測系統。在固定酵素的電極片部分，使用Polyvinylpyrrodine固定尿酸酶，於0.7 V之最佳工作電壓與pH值7.4以及25℃下，尿酸濃度在2~16 mg/dl的範圍內可被良好地判讀出。使用End-point measurement計算模式判讀尿酸濃度可得到與標準濃度溶液和酵素比色法之最佳的相關係數分別為：0.995與0.998。同時，在pH值分別為7.0、7.4、及7.8，25℃下，尿酸感測器的靈敏度不受到顯著的影響。當尿酸濃度高於6 mg/dl，其反應的速率呈現穩定，不受尿酸濃度的增加而影響。然而，檢測低濃度的尿酸時，會受到維他命C的干擾。在保存期限的研究中，於適當的溫度與濕度下，此固定尿酸酶的電極試片的功能可維持到43天。

關鍵字

計算模式 ； 電壓-時間曲線 ； 尿酸感測器 ； 固定尿酸酶電極試片 ； 相關係數。

並列摘要

This work is based upon the characteristic of an enzyme capable to recognize a particular molecule through an oxidation-reduction effect. In this study, the uricase is utilized as the sensing components of our sensor system to initiate biological and subsequent electrochemical reactions. After the reactions, the output infinitesimal currents are transformed into voltages shown as electrical signals. Firstly, the variation of the defined uric acid concentrations is correlated with the dissimilar expression of electrical signals. Secondly, the characteristic voltage-time curves are fairly interpreted using three types of calculation models, End-point measurement, Quasi-kinetic measurement I, and Quasi-kinetic measurement II. Specific uric acid concentrations are thereafter expressed in such sensor system with a built-in special processing algorithm. For the part of the enzyme-attached electrode, polyvinylpyrrodine is utilized to embed the uricase, and under an optimized working voltage of 0.70 V, pH value of 7.4 at 25oC, the uric acid concentration in the range of 2~16 mg/dl can be well distinguished. Using the optimized calculation method of End-point measurement, the correlation coefficient of uric acid concentration with respect to standard solution and colorimetric method can reach to 0.995 and 0.998, respectively. Simultaneously, the sensitivity of measurement of the uric acid sensor is insignificantly affected by the pH values of 7.0, 7.4 and 7.8 at 25oC. The reaction rate of the uricase-attached electrode to uric acid becomes stabilized, or unaffected by the increase of the uric acid concentrations, as the sampling concentrations are higher than 6 mg/dl. Nevertheless, the measurement is likely disturbed by added Vitamin C, as low concentration of uric acid is tested. In the preservation study, the functionability of the uricase-attached electrode, under appropriate temperature and relative humidity, can be hold up to 43 days.

並列關鍵字

Calculation model ； Voltage-time curve ； Correlation coefficient. ； Uricase-attached electrode ； Uric acid sensor

參考文獻

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