The goal of this research is to reduce the hysteresis effect of the urea biosensor modified by urease-silver nanoparticles (Ag NPs)/ruthenium dioxide (RuO2) thin film. A new analog back-end circuit with a voltage regulation approach was proposed for hysteresis reduction. A urea biosensor based on urease-Ag NPs/RuO2 sensing film was fabricated. The sensing characteristics of the urea biosensor such as average sensitivity, response time, and interference effect, were measured by the voltage-time (V-T) measurement system. The experiment results showed that the average sensitivity and linearity of the urea biosensor in a wide range of urea solution (0.833μM-8.33 mM) were 48.73 mV/decade and 0.996, respectively. The response time was 22 seconds and the limit of detection was 0.37 μM. Moreover, the electrochemical impedance analysis (EIS) was used to analyze the charge transfer ability of urease-Ag NPs/RuO2 thin film. By applying the voltage regulation approach, the proposed analog back-end circuit can hold the response voltage of the biosensor at a stable level. Therefore, the hysteresis voltage was reduced. With the proposed backed-end circuit in urea solution cycle of 30 mg/dL → 10 mg/dL → 30 mg/dL → 50 mg/dL → 30 mg/dL, the hysteresis voltage was reduced from 4.57 mV to 3.35 mV (26% reduction) comparing with V-T measurement system. The hysteresis voltage in the opposite urea solution cycle of 30 mg/dL → 50 mg/dL → 30 mg/dL → 10 mg/dL → 30 mg/dL was reduced from 3.71 mV to 2.62 (29% reduction) mV comparing with V-T measurement system.

中文翻译：

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银纳米粒子修饰的尿素生物传感器的滞后减少方法


本研究的目的是降低脲酶银纳米颗粒（Ag NPs）/二氧化钌（RuO2）薄膜修饰的尿素生物传感器的滞后效应。提出了一种采用电压调节方法的新模拟后端电路来减少磁滞。制备了基于脲酶-Ag NPs/RuO2传感膜的尿素生物传感器。通过电压-时间（VT）测量系统测量尿素生物传感器的平均灵敏度、响应时间和干扰效应等传感特性。实验结果表明，尿素生物传感器在较宽范围的尿素溶液（0.833μM-8.33 mM）中的平均灵敏度和线性度分别为48.73 mV/decade和0.996。响应时间为 22 秒，检测限为 0.37 μM。此外，利用电化学阻抗分析（EIS）分析了脲酶-Ag NPs/RuO2薄膜的电荷转移能力。通过应用电压调节方法，所提出的模拟后端电路可以将生物传感器的响应电压保持在稳定的水平。因此，磁滞电压降低。在尿素溶液循环中建议的后端电路为 30 mg/dL → 10 mg/dL → 30 mg/dL → 50 mg/dL → 30 mg/dL 时，迟滞电压从 4.57 mV 降低至 3.35 mV (26 % 减少）与 VT 测量系统相比。与VT相比，30 mg/dL → 50 mg/dL → 30 mg/dL → 10 mg/dL → 30 mg/dL 的相反尿素溶液循环中的滞后电压从 3.71 mV 降低至 2.62 mV（降低 29%） mV测量系统。