title: A Novel Thermal Sensor for the Sensitive Measurement of Chemical Oxygen Demand.
abstract: A novel rapid methodology for determining the chemical oxygen demand (COD) based on a thermal sensor with a flow injection analysis system was proposed and experimentally validated. The ability of this sensor to detect and monitor COD was based on the degree of enthalpy increase when sodium hypochlorite reacted with the organic content in water samples. The measurement results were correlated with COD and were compared against the conventional method using potassium dichromate. The assay required only 5-7 min rather than the 2 h required for evaluation by potassium dichromate. The linear range was 5-1000 mg/L COD, and the limit of detection was very low, 0.74 mg/L COD. Moreover, this method exhibited high tolerance to chloride ions; 0.015 mol/L chloride ions had no influence on the response. Finally, the sensor was used to detect the COD of different water samples; the results were verified by the standard dichromate method.
authors: Institute of Environmental Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. 59040368yaona@sina.cn.|Jingzhou Central Hospital, Jingzhou 434026, China. 59040368yaona@sina.cn.
authors: Na
authors: N
authors: Yao
authors: Institute of Environmental Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. liuzhuan813@163.com.|Yancheng Blood Center, Yancheng 224005, China. liuzhuan813@163.com.
authors: Zhuan
authors: Z
authors: Liu
authors: Hubei Center for Disease Control and Prevention, Wuhan 430079, China. cy_cdc@sina.com.
authors: Ying
authors: Y
authors: Chen
authors: Institute of Environmental Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. zhouyk@mails.tjmu.edu.cn.
authors: Yikai
authors: Y
authors: Zhou
authors: Pure and Applied Biochemistry, Lund University, Box 124, Lund SE-22100, Sweden. bin.xie@tbiokem.lth.se.
authors: Bin
authors: B
authors: Xie
mesh_terms: D057919:Biological Oxygen Demand Analysis / Q000295:instrumentation*; D002138:Calibration; D017022:Flow Injection Analysis / Q000295:instrumentation; D005998:Glycine / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D060106:Lakes / Q000737:chemistry; D057230:Limit of Detection; D012015:Reference Standards; D015203:Reproducibility of Results; D045483:Rivers / Q000737:chemistry; D012815:Signal Processing, Computer-Assisted; D012996:Solutions; D013696:Temperature
chemical_list: D012996:Solutions; D005998:Glycine
keywords: chemical oxygen demand; flow injection analysis system; sodium hypochlorite; thermal sensor