Abstract

A non-enzymatic amperometric sensor using natural molybdenite (MLN) electrodeposited with methylene blue (MB) has been fabricated and characterized and its analytical performances were investigated for the determination of ascorbic acid (AA). The surface morphology of the electrode modified by electrodeposited MB was studied by use of the Advanced Mineral Identification and Characterization System (AMICS) and laser confocal high-temperature scanning microscope (LCSM). The poly(MB) and MLN immobilized sensor showed good stability, reproducibility, sensitivity, and selectivity. It exhibited a linear performance range from 3 to 1000 μM, with a lower detection limit of 0.083 μM (signal/noise = 3) and short response time (< 5 s). No obvious decrease in the current was observed after 20 days storage. The methodology reproducibility of this sensor was 2.6%. It showed good anti-interference ability for the potential interfering compounds. The poly(MB) film not only can enhance the electron-transfer rate but also increase the lifetime of the sensor. This study demonstrated the applicability of natural molybdenite for the fabrication of non-enzymatic electrochemical AA sensor.

中文翻译：

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钼酸修饰的玻碳电极与电沉积亚甲基蓝修饰的灵敏电化学抗坏血酸传感器。

摘要

制备并表征了使用天然钼矿（MLN）电沉积亚甲基蓝（MB）的非酶安培传感器，并对其分析性能进行了研究，以测定抗坏血酸（AA）。使用先进的矿物鉴定和表征系统（AMICS）和激光共聚焦高温扫描显微镜（LCSM）研究了电沉积MB修饰的电极的表面形态。固定有poly（MB）和MLN的传感器显示出良好的稳定性，可重复性，灵敏度和选择性。它的线性性能范围为3至1000μM，检测下限为0.083μM（信号/噪声= 3），响应时间短（<5 s）。储存20天后，没有观察到电流的明显下降。该传感器的方法学重现性为2.6％。对潜在的干扰化合物显示出良好的抗干扰能力。聚（MB）膜不仅可以提高电子传输速率，而且可以延长传感器的使用寿命。这项研究证明了天然辉钼矿在制造非酶电化学AA传感器中的适用性。