Alotaibi K M, Saigl Z M, Alblawi K S, Alwael H, Abduljabbar T N, Mohammed G I, El-Shahawi M S
Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia.
Department of Physical Sciences, Chemistry Division, College of Science, Jazan University, P.O. Box. 114, Jazan, 45142, Saudi Arabia.
J Fluoresc. 2025 Aug 27. doi: 10.1007/s10895-025-04467-9.
Total quantification and speciation of Fe and Fe at trace levels in aqueous environments has emerged as an imperative analytical challenge for ecological systems and public health. Implementation of wavelength-dependent spectrochemical methodologies based on formation of chromogenic Fe chelate for Fe quantification in aqueous media also remains intrinsically challenging owing to intrinsic self-absorbance, and spectral convolution. Thus, the current study reports the development of a direct and selective eco-friendly spectrofluorometric probe for Fe detection in water. The sensor 4, 5- dihydroxy-1, 3-benzenedisulfonic acid (Tiron) displays strong emission which undergoes significant quenching in the fluorescence intensity (at λ = 290/350 nm) upon reaction with Fe at pH 8-9 in the presence of interfering metal ions, allowing for rapid and efficient detection. The probe was sensitive to implement the produced change in color with a total assay reaction time less than 3 min. Detailed spectroscopic investigation reveal a high binding affinity between the Fe ions and the sensor, ascribed to specific complex formation. The limit of detection (LOD) and quantitation (LOQ) and linear dynamic rang (LDR) of the assay were 0.015, 0.04 and 0.05-5 mg L Fe, respectively. The probe was favorably used for total detection and sequential speciation of trace levels of Fe & Fe in water after oxidation of the former to Fe. Spectroscopic studies suggested high coordinating attraction and stability between the sensor and Fe ions. The probe was fruitfully validated by comparing the results with the official inductively coupled plasma-optical emission spectrometry (ICP-OES) data using Student t and F tests signifying the high precision, accuracy and reliability for Fe detection in water samples. The attractive features of the probe comprises its simplicity, no usage of organic solvents, short reaction time; high reactivity, stable response, selective towards Fe, and sensitive for total quantification of iron species. The probe can assist as a talented tool for application in regions of limiting resources specifically concerning iron pollution.
水环境中痕量铁（Fe）的总量定量和形态分析已成为生态系统和公共卫生领域一项紧迫的分析挑战。基于形成用于水介质中铁定量的发色铁螯合物的波长相关光谱化学方法，由于内在的自吸收和光谱卷积，其实施也仍然具有内在挑战性。因此，本研究报告了一种用于水中铁检测的直接、选择性且环保的荧光光谱探针的开发。传感器4,5 - 二羟基 - 1,3 - 苯二磺酸（钛铁试剂）显示出强烈的发射，在pH 8 - 9、存在干扰金属离子的情况下与铁反应时，其荧光强度（在λ = 290/350 nm处）会发生显著猝灭，从而实现快速高效的检测。该探针能够灵敏地呈现颜色变化，并在不到3分钟的总检测反应时间内完成检测。详细的光谱研究表明铁离子与传感器之间具有高结合亲和力，这归因于特定配合物的形成。该检测方法的检测限（LOD）、定量限（LOQ）和线性动态范围（LDR）分别为0.015、0.04和0.05 - 5 mg/L Fe。该探针在将水中的亚铁氧化为铁后，可有效地用于水中痕量铁和亚铁的总量检测及连续形态分析。光谱研究表明传感器与铁离子之间具有高配位吸引力和稳定性。通过使用学生t检验和F检验将结果与官方电感耦合等离子体发射光谱法（ICP - OES）数据进行比较，该探针得到了有效验证，表明其在水样中铁检测方面具有高精度、高准确性和高可靠性。该探针的吸引人之处包括其简单性、不使用有机溶剂、反应时间短；高反应活性、稳定响应、对铁具有选择性以及对铁物种的总量定量敏感。该探针可作为一种有价值的工具，应用于资源有限且特别关注铁污染的地区。
