使用离子选择性电极同时测量水和土壤样本中的酸盐和:解决灵敏度和精度问题
Tolulope Fayose1, Ellen Thomas1, Tanja Radu2
1The Birchall Centre Lennard-Jones Laboratories Keele University Keele Staffordshire UK.
Analytical science advances
|May 8, 2024
概括
低成本的离子选择性电极 (ISE) 能够灵敏精确地检测土壤和水中的 (NH4+) 和 (NO3-). 这项技术可以有效地管理环境监测的活性负载.
科学领域:
- 环境化学环境化学
- 分析化学 分析化学
- 土壤科学 土壤科学
背景情况:
- 反应性加载给环境带来了重大挑战.
- 对氨 (NH4+) 和 (NO3-) 的有效监测对于土壤和水资源管理至关重要.
- 现有的实验室技术对于频繁的现场分析可能耗时且昂贵.
研究的目的:
- 证明低成本离子选择性电极 (ISE) 的适用性,灵敏性和精度,用于同时检测NH4+和NO3.
- 开发和验证使用ISE进行样本准备和分析的简化方法.
- 使技术和非技术最终用户能够进行高效的土壤和水资源管理.
主要方法:
- 开发一种简化样本准备和分析方法,用于ISEs.
- 与流量注入分析 (FIA) 和便携式色度测试 ISEs 的比较.
- 应用线性回归和贝叶斯非线性校准,包括直接电位计和标准加法模式.
- 在各种土壤和水样中的NH4+和NO3-度范围内验证ISEs.
主要成果:
- 测试结果显示,ISE对于同时检测NH4+和NO3具有很高的适应性,灵敏度和精度.
- 开发的方法与已建立的实验室和便携式技术有很好的一致性.
- 观察到精度和灵敏度的改善,置信区间减少了50-60%.
- 利用整个ISE响应曲线将从线性近似中最小化偏差.
结论:
- 低成本,易于使用的IEE是用于高频矿物测量的强大工具.
- 这项技术可以显著提高对转化过程的理解.
- 在应对土地利用,施肥和气候变化影响方面,ISE促进了更好的土壤和水资源管理.
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