基于微流控芯片的臭氧化学发光法测量海水化学需氧量(COD)分析系统的研究

摘要

海水化学需氧量(COD)是海水中有机污染物的综合指标,是海洋环境监测最重要的项目之一.现有的海水COD测量方法耗时长、体系复杂,无法满足海洋在线监测的需求.采用臭氧发光机理实现海水COD的分析,同时借助微芯片技术,设计了高集成度的新型海水COD分析系统,同时对系统中臭氧和水样流速、水样加热温度、样品盐度及过滤精度等影响测定的因素进行优化筛选.实验结果表明,该系统的测量范围为0.1~10mg·L-1,检出限0.08mg·L-1,与国标方法测量结果有很好的一致性,同时具有结构简单,测试时间短等优势,满足海水COD现场分析的需求.%Chemical oxygen demand (COD) is a comprehensive index of organic pollutants in seawater ,which is one of the most important items in marine environmental monitoring .The existing COD measurement methods are time-consuming and complex , which cannot meet the needs of online marine monitoring .This paper designs an integrating Microfluidic analysis system for COD using ozone chemiluminescence analysis .Different factors that influences on determination were optimized ,including ozone and water flow rate ,water temperature ,salinity and filtration of the sample ,etc .The experimental results have shown that this system can realize the analysis of 0.1~10 mg · L -1COD in seawater ,the detection limit is 0.08 mg · L -1 ,and the measurement results are well consistent with the national standard method ,Besides ,it has the advantages of simple structure ,short test time , meet the requirements of field analysis of seawater COD .