用四甲基二 (TMB) 作为指标在水中测定Cr(VI) 的色度
Ramij Raja1, Dhruba Jyoti Sarkar1, Ayan Biswas1
1Aquatic Environmental Biotechnology Division, ICAR-Central Inland Fisheries Research Institute (ICAR-CIFRI), Barrackpore, Kolkata-700120, West Bengal, India.
概括
一种新的色度测量方法使用TMB和H2O2.2检测六价 (CrVI). 这种简单,高效的技术,增强EDTA,准确监测环境水样中的CrVI.
科学领域:
- 环境化学环境化学
- 分析化学 分析化学
- 毒理学 毒理学 毒理学
背景情况:
- 六价 (CrVI) 是一个重要的环境和健康危害.
- 现有的crvi监测分析方法可能很复杂或缺乏效率.
- 需要简单,稳固和高效的方法来检测环境CrVI.
研究的目的:
- 开发一种简单,强大和高效的色度分析方法来检测CrVI.
- 优化环境监测应用的方法.
- 为了验证该方法的性能与既定的监管限制.
主要方法:
- 使用TMB (3,3',5,5'-四甲基胺) 作为指标在存在H2O2.2.的情况下对CrVI的色度检测.
- 针对CrVI检测的反应条件的优化.
- 在样品制备中加入EDTA以减轻其他金属离子的干扰.
- 使用强化水样本验证方法,并与世卫组织和美国环保署标准进行比较.
主要成果:
- 最优化的方法显示出良好的线性 (r2 = 0.9944),检测极限 (LOD) 为0.009 mg/L.
- 添加EDTA改善了CrVI恢复 (81.73-111.40%) 并减少了假阳性.
- 使用EDTA增强的方法显示出极好的线性 (r2 = 0.9952) 和0.023 mg/L的检测极限,低于世卫组织和美国环保署的限制.
- 该方法在天然水样本中被证明是有效的,表明了实时环境监测的潜力.
结论:
- 已成功开发出一种简单,高效和强大的色度测量方法来检测CrVI.
- 包括EDTA在内显著提高了方法的可靠性,通过尽量减少干扰.
- 开发的分析技术符合饮用水的监管标准,并显示了无纳米材料的实时环境CrVI监测的前景.
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