Miniaturized electrochemical sensor with micropillar array working electrode for trace lead online measurement in tap water
10 Jun 2019-Journal of Micromechanics and Microengineering (IOP Publishing)-Vol. 29, Iss: 10, pp 105005
TL;DR: In this paper, a compact, durable, low-reagent-usage, portable miniaturized electrochemical sensor is successfully developed for the high sensitivity detection of trace lead in tap and lake samples.
Abstract: A compact, durable, low-reagent-usage, portable miniaturized electrochemical sensor is successfully developed for the high sensitivity detection of trace lead. We fabricated micropillars array working electrodes on the chip and established ultra-low concentration sodium acetate-acetate (NaAC-HAC) buffers (pH≈4.5) system to enhance the detection sensitivity of the sensor. The ultra-low concentration buffer possesses unique features of low baseline current and high peak current difference height. The analytical performance of the fabricated electrochemical sensor with three-dimensional gold (Au) working electrodes modified by Bismuth-film was comprehensively studied. The microsensor exhibited a high sensitivity of 0.0412μAppb−1 and a satisfactory detection limit of 0.15ppb when detecting lead ions under optimized conditions. Moreover, good linearity (correlation coefficient: 0.9993) with lead ions measurement in the concentration range of 1 to 120ppb and excellent repeatability (RSD: 1.79%) was obtained. the chip has satisfactory selectivity for common Interference ion. Besides, a low consumption of 350 μL of reagents per test was acquired. Finally, the proposed microsensor was applied to detect trace metal ions in tap and lake samples with satisfactory results.
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TL;DR: Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, Jilin 130024, China Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Kunming, Yunnan 650500.
Abstract: Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, Jilin 130024, China Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming, Yunnan 650500, China State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China Northwest Land and Resources Research Center, Shaanxi Normal Northwest University, China State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, Changchun, Jilin 130024, China Ecology and Environment Department of Jilin Province, Changchun, Jilin 130024, China Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region, Heilongjiang University, Harbin 150080, China School of Life Science and Geology, Yili Normal University, Yili, Xinjiang 835000, China
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