State Key Laboratory of Marine Environmental Science, Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Center for Marine Environmental Chemistry and Toxicology, College of the Environment & Ecology , Xiamen University , 361102 , Xiamen , China.
Department of Environmental Sciences , University of California , Riverside , California 92521 , United States.
Environ Sci Technol. 2019 Mar 5;53(5):2579-2585. doi: 10.1021/acs.est.8b03760. Epub 2019 Feb 15.
Active samplers for ambient monitoring of trace contaminants in surface water are highly desirable, but their use is often constrained by power supply. Here, we proposed a novel solution by coupling an improved osmotic pump (OP) with a solid-phase extraction (SPE) cartridge to construct a power-free active sampler for organic contaminants. The OP simply consisted of two cylindrical chambers separated by a reverse osmosis membrane. We, for the first time, added ion-exchange resins into the OP inlet chamber and successfully constructed OPs with a smooth and constant flow. In the OP-SPE sampler, water was continuously drawn through the SPE cartridge at a constant flow, and time-weighted average concentration over the sampling course may be easily calculated from the amount of target analytes retained on the SPE cartridge and water collected in the sampler. The OP-SPE samplers were deployed in a river to detect herbicides, and the measured concentrations were largely in agreement with the average of 11 daily spot samples. Given that a wide range of SPE cartridges are available for different classes of organic contaminants, this approach is versatile and may find widespread applications for in situ sampling of surface water under different conditions, including poorly accessible locations.
用于环境监测地表水痕量污染物的主动采样器非常理想，但由于电源的限制，其使用往往受到限制。在这里，我们提出了一种新的解决方案，即将改进的渗透泵（OP）与固相萃取（SPE）小柱耦合，构建一种无需电源的有机污染物主动采样器。OP 仅由两个圆柱形腔室组成，通过反渗透膜隔开。我们首次将离子交换树脂添加到 OP 入口腔室中，并成功构建了具有平稳且恒定流量的 OP。在 OP-SPE 采样器中，水以恒定流量持续通过 SPE 小柱抽取，从 SPE 小柱上保留的目标分析物的量和采样器中收集的水中可以很容易地计算出采样过程中的时间加权平均浓度。OP-SPE 采样器被部署在一条河流中以检测除草剂，测量浓度与 11 个每日点样的平均值基本一致。鉴于有多种 SPE 小柱可用于不同类别的有机污染物，因此该方法具有通用性，可广泛应用于不同条件下的地表水原位采样，包括难以到达的地点。
