Colorimetric and fluorescent dual mode detection of Fe (III) ion in blood samples in combination with cloud point extraction

[Display omitted] •For accurate identification and measurement of iron, cloud point extraction and spectrophotometry were used.•The process involved complex formation between ferric iron and mesalazine.•The formed complex was extracted into a Triton X-114-rich nonionic surfactant phase for further analysis.•Iron was effectively identified and quantified in biological samples using the methods that were developed. Both cloud point extraction and spectrophotometry, as well as cloud point extraction and spectrofluorometry, were developed to achieve sensitive and selective identification and measurement of iron. The technique relies on forming a complex between ferric iron (Fe3+) and 5-amino salicylic acid (MSZ), also known as mesalazine reagent. This complex is then extracted into a Triton X-114-rich nonionic surfactant phase.At a wavelength of 550 nm, spectrophotometric analysis of the extracted complex is performed. The other method employs spectrofluorometric determination, which entails quenching the fluorescence intensity of the mesalazine reagent. The excitation wavelength for this determination is 338 nm,and the emission wavelength is 496 nm.These two methods have a dynamic linear range of 1 to 23 μg mL−1 for colorimetry with a detection limit and enrichment factor of 0.0121 μg mL−1 and 4.52, respectively, and 0.1 to 1.4 μg mL−1, with a detection limit of 0.0053 μg mL−1 for fluorimetry.Spiked samples (artificially enriched with iron) were used to evaluate the method's accuracy. The procedures were also deployed successfully to identify and quantify iron in biological samples, yielding positive results. In addition, the analytical results are statistically consistent with those derived from a stimulation procedure, further validating the method's reliability.