title: A Low Cost Compact Measurement System Constructed Using a Smart Electrochemical Sensor for the Real-Time Discrimination of Fruit Ripening.
abstract: Ethylene as an indicator for evaluating fruit ripening can be measured by very sensitive electrochemical gas sensors based on a high-resolution current produced by a bias potential applied to the electrodes. For this purpose, a measurement system for monitoring ethylene gas concentrations to evaluate fruit ripening by using the electrochemical ethylene sensor was successfully developed. Before the electrochemical ethylene sensor was used to measure the ethylene gas concentrations released from fruits, a calibration curve was established by the standard ethylene gases at concentrations of 2.99 ppm, 4.99 ppm, 8.01 ppm and 10 ppm, respectively, with a flow rate of 0.4 L·min(-1). From the calibration curve, the linear relationship between the responses and concentrations of ethylene gas was obtained in the range of 0-10 ppm with the correlation coefficient R² of 0.9976. The micropump and a novel signal conditioning circuit were implemented in this measurement, resulting in a rapid response in detecting ethylene concentrations down to 0.1 ppm in air and in under 50 s. In this experiment, three kinds of fruits-apples, pears and kiwifruits-were studied at a low concentration (under 0.8 ppm) of trace ethylene content in the air exhaled by fruits. The experimental results showed that a low cost, compact measurement system constructed by using an electrochemical ethylene sensor has a high sensitivity of 0.3907 V·ppm(-1) with a theoretical detection limit of 0.413 ppm, and is non-invasive and highly portable.
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. mlz0124@126.com.|State Key Laboratory of Wheat and Maize Crop Science, Zhengzhou 450002, China. mlz0124@126.com.
authors.forename: Liuzheng
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. wangling0351@126.com.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. chen_ruipeng@yeah.net.|State Key Laboratory of Wheat and Maize Crop Science, Zhengzhou 450002, China. chen_ruipeng@yeah.net.
authors.forename: Ruipeng
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. changkeke927@163.com.
authors.forename: Keke
authors.initials: K
authors.lastname: Chang
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. wangshun6518@163.com.|State Key Laboratory of Wheat and Maize Crop Science, Zhengzhou 450002, China. wangshun6518@163.com.
authors.forename: Shun
authors.initials: S
authors.lastname: Wang
authors.affiliation: School of Human Nutrition and Dietetics, McGill University, Macdonald Campus, 21, 111 Lakeshore Road, Ste Anne de Bellevue, QC H9X 3V9, Canada. xinran.hu@mail.mcgill.ca.
authors.forename: Xinran
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. xiaohuosun89@163.com.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. zhaohuilulu@163.com.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. haifengdreams@sina.cn.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. guo_qingqian@163.com.
authors.forename: Qingqian
authors.initials: Q
authors.lastname: Guo
authors.affiliation: College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China. jm_hu@163.com.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Department of Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China. jdhu@henau.edu.cn.|State Key Laboratory of Wheat and Maize Crop Science, Zhengzhou 450002, China. jdhu@henau.edu.cn.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Hu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D055664:Electrochemical Techniques; D005030:Ethylenes / Q000302:isolation & purification* / Q000378:metabolism; D005638:Fruit / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism; D005740:Gases / Q000302:isolation & purification* / Q000378:metabolism; D057230:Limit of Detection
chemical_list: D005030:Ethylenes; D005740:Gases; C036216:ethylene
keywords: electrochemical sensor; ethylene gas; fruit ripening; micropump; non-invasive