A novel passive sampler based on gas-diffusion across a hydrophobic membrane is described for the determination of the time-weighted average concentration of dissolved molecular ammonia in high ionic strength aquatic environments, such as sea, coastal and estuarine waters, for a period of 3 days. The passive sampler developed is cheap, easy-to-use, reusable, and has a dynamic concentration range of 2.0–12 µM, which covers the water quality guideline trigger value of 11.4 µM (160 µg L⁻¹ NH₃-N) for high conservation value waters, making this a powerful new tool for water quality managers involved in long-term ammonia monitoring. The gas-diffusion-based passive sampler was calibrated under laboratory conditions and deployed in a tank of seawater in the laboratory and at an estuarine site for proof of concept, and a good agreement between passive and spot sampling was achieved in both cases.

描述了一种基于气体在疏水膜上扩散的新型无源采样器，用于确定在高离子强度水生环境（如海水，沿海和河口水域）中溶解的氨的时间加权平均浓度，时间为3天。开发的无源采样器价格便宜，易于使用，可重复使用，并且动态浓度范围为2.0–12 µM，涵盖了11.4 µM（160 µg L ^-1 NH _3的水质准则触发值）-N）用于具有高保护价值的水，这使其成为参与长期氨监测的水质管理人员的有力新工具。基于气体扩散的无源采样器在实验室条件下进行了校准，并被部署在实验室和河口站点的海水罐中，以证明其概念，并且在两种情况下都实现了无源采样与现场采样之间的良好协议。