Underwater Systems laboratory, Centre for Marine MicroSystems, National Oceanography Centre, European Way, Southampton SO14 3ZH, UK.
Environ Sci Technol. 2012 Jul 3;46(13):7293-300. doi: 10.1021/es300226y. Epub 2012 Jun 15.
We present the design of an osmotic water sampler that is adapted to and validated in freshwater. The sample is drawn into and stored in a continuous narrow bore tube. This geometry and slow pump rate (which is temperature dependent: 0.8 mL/d at 4 °C to 2.0 mL/d at 28 °C) minimizes sample dispersion. We have implemented in situ time-stamping which enables accurate study of pump rates and sample time defining procedures in field deployments and comparison with laboratory measurements. Temperature variations are common in rivers, and without an accurate time-stamping, or other defining procedure, time of sampling is ambiguous. The sampler was deployed for one month in a river, and its performance was evaluated by comparison with manually collected samples. Samples were analyzed for major ions using Ion Chromatography and collision reaction Inductively Couple Mass Spectrometry. Despite the differences of the two sampling methods (osmotic sampler averages, while manual samples provide snapshots), the two data sets show good agreement (average R(2) ≈ 0.7), indicating the reliability of the sampler and at the same time highlighting the advantages of high frequency sampling in dynamic environments.
我们设计了一种适用于淡水并经过验证的渗透压采样器。样品被吸入并储存在连续的细管中。这种几何形状和缓慢的泵送速率（受温度影响：4°C 时为 0.8 毫升/天，28°C 时为 2.0 毫升/天）最大限度地减少了样品的分散。我们已经实现了原位时间戳功能，这使得可以在现场部署中准确研究泵送速率和样品时间定义程序，并与实验室测量进行比较。河流中温度变化很常见，如果没有准确的时间戳或其他定义程序，采样时间就会不明确。该采样器在一条河流中部署了一个月，并通过与手动采集的样本进行比较来评估其性能。使用离子色谱法和碰撞反应电感耦合质谱法分析样品中的主要离子。尽管两种采样方法存在差异（渗透压采样器平均值，而手动样本提供快照），但这两个数据集显示出良好的一致性（平均 R(2)≈0.7），这表明了采样器的可靠性，同时突出了在动态环境中进行高频采样的优势。
