A flow-based method for the spectrophotometric determination of iron in recreational waters, both fresh and marine (variable salinity content), was developed. For that purpose, 3-hydroxy-4-pyrydinone ligand functionalized with an ether function was synthetized and used as chromogenic chelator (1-(3′-methoxypropyl)-2-methyl-3-benzyloxy-4-(1H)pyridinone - MRB13) for iron quantification. This water-soluble reagent was previously reported as a greener alternative to quantify iron, due to its low toxicity and a more environmental friendly synthesis. Furthermore, it also displayed a high affinity and specificity for iron. With the main objective of quantifying iron in a variety of water types (different matrices and iron content), two strategies were developed, one of them including on-line solid-phase extraction (SPE), and the other without resorting to a SPE process. Water matrix clean-up and iron enrichment was achieved using a nitrilotriacetic acid resin column. The potential interference of metal ions usually present in water samples was assessed and no significant interference (<10%) was observed. The limits of detection were 11 and 2.9 μg L⁻¹ without and with SPE, respectively. For one determination (three replicates), the corresponding consumption of MRB13 is 90 μg, sodium hydroxide is 1.4 mg, and boric acid is 5.6 mg. The method was applied to certified water samples and the results were in agreement with certified values. The developed method was also applied to fresh and marine water, and recovery ratios of 103 ± 4 and 101 ± 7 without and with SPE, respectively, were achieved.

开发了一种基于流动的分光光度法测定淡水和海水（含盐量可变）中的水中铁的方法。为此目的，合成了以醚官能团官能化的3-羟基-4-吡啶酮配体，并用作发色螯合剂（1-（3'-甲氧基丙基）-2-甲基-3-苄氧基-4-（1H）吡啶酮-MRB13 ）进行铁定量。以前据报道，这种水溶性试剂因其低毒性和更环保的合成方法而成为定量铁的绿色替代品。此外，它还显示出对铁的高亲和力和特异性。为了量化各种水类型（不同基质和铁含量）中的铁，其主要目的是开发了两种策略，其中一种包括在线固相萃取（SPE），另一个不求助于SPE流程。使用次氮基三乙酸树脂色谱柱净化水基质并富集铁。评估了水样品中通常存在的金属离子的潜在干扰，未观察到明显的干扰（<10％）。检测限为11和2.9μgL^-1分别不带SPE和带SPE。对于一次测定（三次重复），相应的MRB13消耗量为90μg，氢氧化钠为1.4 mg，硼酸为5.6 mg。该方法应用于认证的水样，结果与认证值一致。所开发的方法还适用于淡水和海水，在不使用和使用固相萃取的情况下，回收率分别为103±4和101±7。