Pt基微纳结构无酶葡萄糖传感器的构建和性能研究

关键词：无酶 葡萄糖传感器 Pt 纳米花 Pt-Pb 纳米锥 不锈钢针电极 电沉积
ABSTRACT
ABΒιβλιοθήκη BaiduTRACT
The poor sensitivity, repeatability and stability of the enzymatic sensors remain as problems for real sensor applications. Direct electrocatalytic oxidation of glucose at an enzyme-free electrode would exhibit conveniences and advantages to avoid the drawbacks of the enzymatic electrode. Therefore, the development of needle-type nonenzymatic glucose biosensor provides a promising method for glucose detection. Pt nanoflowers were fabricated by using template- free ultrasonic electrodeposition method. The Pt nanoflowers electrode exhibited excellent catalytic activity towards glucose oxidation in the present and in the absence of chloride ions. The results showed that the sensitivity of the electrode to glucose oxidation was 1.87 μAcm−2 mM−1 with a linear range from 1 mM to 16 mM and detection limit of 48 µ M. In addition, the nonenzymatic glucose sensors exhibited excellent selectivity, stability and repeatability. This indicated that nanoflower structure exhibit advantages to avoid the drawbacks of bare Pt electrode, and thus selectivilty, sensitivity, stability and repeatability of the sensors can be improved. Pinecone–shaped Pt–Pb nanocone electrode was prepared on the bare Au electrodes by electrochemical deposition. The synthesized pinecone–shaped Pt–Pb nanocone electrode exhibited strong and sensitive current responses to glucose at a negative potential in the present and in the absence of chloride ions. In the Pt–Pb binary system, Pb can considerably accelerate glucose electrooxidation at Pt electrodes but it exhibited no direct catalytic effect towards glucose. Therefore, glucose oxidation at the Pt–Pb mainly followed the reaction pathway of glucose oxidation at Pt electrode. The sensitivity of the sensor was 10.71 μA mM−1 cm−2 with linearity up to 12 mM and a detection limit of 8.4 μM. In addition, the as–prepared nonenzyme glucose sensor exhibited acceptable repeatability, stability and reproducibility for determination of glucose. The response current increased with the temperature in the range from 20 º C to 70 º C, and became stable when the temperature was above 70 º C. Therefore, the sensor exhibited a wide range of applications compared with enzymatic biosensor. Pt–Ag and Pt–Cu hollow nanoparticles were fabricated by galvanic replacement. Electrochemical results showed that Cu and Ag can considerably accelerate glucose electrooxidation at Pt electrodes, but the electrooxidation potential increased. The sensitivity of the sensor based on Pt– Ag hollow nanoparticles was 7.64 μAmM−1 cm−2
天津大学材料科学与工程学院 二零一二年五月
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摘要
0.03–9 mM ，响应灵敏度为 0.4485 μAcm−2 mM−1 （ R=0.9995），最低检测限为 200 µ M。 用直径为 0.35 mm 的不锈钢针灸针作为工作电极，用恒电流沉积法构建 PtPb 纳米颗粒修饰不锈钢针式无酶葡萄糖传感器。构建的针式无酶传感器对葡萄 糖 的 线 性 检 测 范 围 为 1.5 mM–24 mM ， 响 应 灵 敏 度 为 3.33 μAcm−2 mM−1 （R=0.9997），最低检测限为 27 μM。传感器具有很好的选择性、稳定性以及 重复性。与针式酶葡萄糖传感器相比，针式无酶葡萄糖传感器具有高的稳定 性、选择性和灵敏度。
Pt 基微纳结构无酶葡萄糖传感器的 构建和性能研究 Fabrication and Study of Performance of Nonenzymatic Glucose Sensor Based on Pt – Based Micro-Nano structure
学科专业：材料学 研 究 生：郭美卿 指导教师：许鑫华 教授
ABSTRACT
with linear range from 0.5 mM to 16 mM and a detection limit of 11.78 μM. The sensitivity of the sensor based on Pt–Cu hollow nanoparticles was 8.04 μAmM−1 cm−2 with linear range from 0.5 mM to 14 mM and a detection limit of 11.19 μM. The nonenzymatic sensors based on Pt– Ag and Pt–Cu hollow nanoparticles showed acceptable stability and repeatability. An enzymatic glucose biosensor was fabricated by electrodepositing chitosan– glucose oxidase biocomposite onto the stainless steel needle electrode modified by Pt–Pb nanoparticles. The linear range of the proposed biosensor was from 0.03 to 9 mM with a current sensitivity of 0.4485 µ AmM−1 and a detection limit of 200 μM. This work confirmed that the fabrication method of the needle-type glucose biosensor was feasible. A nonenzymatic glucose biosensor was fabricated by electrodepositing Pt–Pb nanoparticles onto the stainless steel needle electrode. The results showed that the sensitivity of the electrodes to glucose was 3.33 μAcm−2 mM−1 with liner range from 1.5 mM–24 mM and detection limit of 27 μM. In addition, the nonenzymatic glucose sensors exhibited excellent selectivity, stability and repeatability. Compared with the enzymatic glucose biosensors, the nonenzyme sensors exhibited high stability, sensitility and repeatability.
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摘要
中文摘要
葡萄糖酶传感器由于稳定性、重复性、灵敏度、选择性较差及外径较大的 缺点使其应用受到限制，无酶葡萄糖传感器利用葡萄糖在电极表面直接发生电 催化氧化对其进行检测，能够避免酶传感器的不足。因此，可植入式无酶葡萄 糖传感器的发展为血糖监测提供了新的途径。 采用恒电位沉积法制备 Pt 纳米花电极，Pt 纳米花电极对葡萄糖具有很好的 电催化性能，在含有氯离子的溶液中不会失活。构建的无酶葡萄糖传感器的线 性响应范围为 1 mM–16 mM，响应灵敏度为 1.87 μAcm−2 mM−1 （R=0.9993）， 最低检测限为 48 µ M（S/N=3）。传感器具有很好的重现性、重复性、稳定性和 选择性，表明纳米花结构能够改善裸 Pt 电极的不足，提高传感器的选择性、灵 敏度、重复性以及稳定性。 采用恒电流沉积法制备松树花状 Pt–Pb 纳米锥电极，该电极对葡萄糖具有 很好的电催化性能，在含有氯离子的溶液中不会失活。对葡萄糖的电催化氧化 过程遵守葡萄糖在 Pt 电极表面的反应机理，Pb 对葡萄糖没有直接的电催化氧化 活性，但是能够提高 Pt 电极的电催化性能。构建的无酶传感器对葡萄糖的线性 检测范围为 0.5 mM–12 mM，灵敏度为 10.71 μAcm−2 mM−1 （R=0.9997），最低 检测限为 8.4 μM。传感器具有很好的选择性、稳定性和重复性。此外，在 20 º C 到 70 º C 的范围内，松树花状 Pt–Pb 纳米锥电极对葡萄糖的电催化活性随温 度的升高而增大，当温度超过 70 º C 之后，活性趋于稳定。因此，该无酶葡萄 糖传感器的工作温度范围宽，相比酶传感器将有更加广泛的应用。 采用电流置换反应制备 Pt–Ag 和 Pt–Cu 中空纳米颗粒电极，研究表明添加 Ag 与 Cu 能够提高 Pt 电极对葡萄糖的电催化氧化活性，同时会提高葡萄糖在电 极表面的电催化氧化电位。Pt– Ag 和 Pt–Cu 中空纳米颗粒修饰电极构建的无酶 葡萄糖传感器的线性检测范围分别为 0.5 mM–16 mM 和 0.5 mM–14 mM，响应 灵敏度分别为 7.64 μAcm−2 mM−1 和 8.04 μAcm−2 mM−1 ，最低检测限分别为 11.78 μM 和 11.19 μM ，传感器对抗坏血酸和尿酸的响应电流是葡萄糖响应电流的 15 %和 9 %。 用直径为 0.35 mm 的不锈钢针灸针作为工作电极，基于 Pt-Pb 纳米颗粒电 活性面积高、壳聚糖易成膜及生物相容性好的优势，用恒电流沉积法结合苯醌 还原诱导壳聚糖沉积的方法构建针式酶葡萄糖传感器。针电极对葡萄糖具有很 好的电催化氧化性能，说明苯醌电还原诱导壳聚糖与葡萄糖氧化酶共沉积制备 针式酶电极的方法是可行的。构建的针式酶葡萄糖传感器的线性检测范围为