A design of spectrophotometric microfluidic chip sensor for analyzing silicate in seawater

3rd International Conference on Water Resource and Environment

地球科学;生态环境科学

Cao, X.^1,2 ; Zhang, S.W.^1,2 ; Chu, D.Z.^1,2 ; Wu, N.^1,2 ; Ma, H.K.^1,2 ; Liu, Y.^1,2

Institute of Oceanographic Instrument, Shandong Academy of Science, Qingdao Shandong

266001, China^1

Shandong Ocean Environment Monitoring Technology Key Laboratory, Qingdao Shandong

266001, China^2

关键词: Ammonium molybdate;    Analytical performance;    Anti-interference;    Biogeochemical cycle;    Continuous flow analysis;    Limit of detection;    Reaction mechanism;    Reliability and robustness;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/82/1/012080/pdf
DOI  :  10.1088/1755-1315/82/1/012080

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

High quality and continuous in situ silicate data are required to investigate the mechanism of the biogeochemical cycles and the formation of red tide. There is an urgently growing need for autonomous in situ silicate instruments that perform determination on various platforms. However, due to the high reagents and power consumption, as well as high system complexity leading to low reliability and robustness, the performance of the commercially available silicate sensors is not satisfactory. With these problems, here we present a new generation of microfluidic continuous flow analysis silicate sensor with sufficient analytical performance and robustness, for in situ determination of soluble silicate in seawater. The reaction mechanism of this sensor is based on the reaction of silicate with ammonium molybdate to form a yellow silicomolybdate complex and further reduction to silicomoIybdenum blue by ascorbic acid. The minimum limit of detection was 45.1 nmol L-1, and the linear determination range of the sensor is 0-400 μmol L-1. The recovery rate of the actual water is between 98.1%-104.0%, and the analyzing cycle of the sensor is about 5 minutes. This sensor has the advantages of high accuracy, high integration, low water consumption, and strong anti-interference ability. It has been successfully applied to measuring the silicate in seawater in Jiaozhou Bay.