CLOUD POINT EXTRACTION PRECONCENTRATION AND SPECTROPHOTOMETRIC DETERMINATION OF MOLYBDENUM(VI) USING 7,8-DIHYDROXY-2,4-DIPHENYLBENZOPYRYLIUM PERCHLORATE
DOI:
https://doi.org/10.15421/jchemtech.v34i2.358415Keywords:
cloud point extraction, initiators, spectrophotometry, Molybdenum(VI), optical emission spectroscopy with inductively coupled plasmaAbstract
In this work, the conditions for cloud point extraction preconcentration of Mo(VI) in the form of a complex with perchlorate of 7,8-dihydroxy-2,4-diphenylbenzopyrylium into the micellar phase of the nonionic surfactant Triton X-100 were investigated and optimized. It was established that the addition of sodium salicylate to the system at pH 1.7 and a Triton X-100 concentration of 0.5 vol.% induces phase separation and micellar phase formation at room temperature, which simplifies the extraction procedure and avoids additional heating. Under the selected conditions, effective preconcentration of the analyte and stable spectrophotometric response were achieved. Based on these results, a spectrophotometric procedure was proposed for the determination of Mo(VI) after cloud point extraction. The calibration plot was linear in the concentration range of 8–320 μg/L. The limits of detection and quantification were 2.4 and 8.0 μg/L, respectively. The developed method was successfully applied to model solutions and a biologically active supplement, and the relative standard deviation did not exceed 5.0 %.
References
Tarafder, P. K., Mondal, R. K. (2011). A review on the complex forming ability of O-O′ type ligands with transition metals: Introducing 2,3-dihydroxynaphthalene as a potential analytical reagent. Reviews in Analytical Chemistry, 30(2), 73–81. https://doi.org/10.1515/REVAC.2011.016
Pyrzynska, K. (2007). Determination of molybdenum in environmental samples. Analytica Chimica Acta, 590(1), 40–48. https://doi.org/10.1016/j.aca.2007.03.013
Marczenko, Z., Balcerzak, M. (1998). Spectrophotometric methods in inorganic analysis. Wydawnictwo Naukowe PWN.
Zhukovetska, O. M., Guzenko, E. M., Chebotarev, A. N., Snigur, D. V. (2022). Solid-phase spectrophotometric determination of Mo(VI) using organopolymeric cation exchange resin KU-2-8 modified by 6,7-dihydroxy-2-phenyl-4-methylbenzopyrylium chloride. Methods and Objects of Chemical Analysis, 17, 10–16. http://dx.doi.org/10.17721/moca.2022.10-16
Snihur, K., Zhukovetska, O., Al-Muhanna, E. A., Guzenko, O., Azooz, E. A., Snigur, D. (2026). Mixed micelles assisted room-temperature cloud point extraction for preconcentration and spectrophotometric determination of Molybdenum(VI). Talanta, 298, 129011. http://dx.doi.org/10.1016/j.talanta.2025.129011
Chebotarev, O. M., Toporov, S. V., Snіgur, D. V., Barbalat, D. O. (2021). Pohidni 6,7- ta 7,8-dygidroksybenzopiryliju: syntez, vlastyvosti ta analitychne zastosuvannja (ogljad) [Derivatives of 6,7- and 7,8-dihydroxybenzopyrylium: synthesis, properties and analytical application (review)]. Odesa National University Herald. Chemistry, 26(2(78)), 73–88. https://doi.org/10.18524/2304-0947.2021.2(78).233829
Nagalakshmi, K. V., Shyamala, P., Khan, Sk. A., Puranam, D. H. (2025). Cloud Point Extraction Method for Separation and Preconcentration of Molybdenum and Zirconium Using Mixture of Surfactants from Natural Waters and their Determination by Spectrophotometry. Methods and Objects of Chemical Analysis, 19(3), 160–166. http://dx.doi.org/10.17721/moca.2024.160-166
Divarova, V., Gajdošová, A., Racheva, P., Gavazov, K. (2025). An Ionic liquid-assisted mixed micelle-mediated centrifuge-less cloud point extraction spectrophotometric method for the determination of molybdenum (VI). International Journal of Molecular Sciences, 26(10), 4597. https://doi.org/10.3390/ijms26104597
Azooz, E. A., Abdellah, I. M., Eletmany, M. R., Zhukovetska, O., Snigur, D. (2025). Automatic microextraction methods for forensic drugs analysis: principles, recent trends, challenges, and applications. Green Analytical Methods and Miniaturized Sample Preparation Techniques for Forensic Drug Analysis, 421–456. https://doi.org/10.1016/B978-0-443-13907-9.00017-6
Kulichenko, S. A., Shcherbyna, M. H. (2012). Kolorimetrychne vyznachennia molibdenu v mitseliarnykh ekstraktakh kationnoi PAR [Colorimetric determination of molybdenum in micellar extracts of cationic surfactant]. Methods and Objects of Chemical Analysis, 7(1), 39–44.
Niu, S. Q., Jin, Q. Z., Fan, K. Y., Cao, J. (2026). Ultrasonic assisted micellar extraction and in situ cloud point enrichment of terpenoids in complex matrices using poloxamer as a novel surfactant. Journal of Chromatography A, 1777, 466949. https://doi.org/10.1016/j.chroma.2026.466949
Snigur, D., Zhukovetska, O., Demchuk, A., Chyzh, I., Azooz, E. A. (2026). Environment-friendly Solvents for Sustainable Extraction Processes. Sustainable Analytical Chemistry: Methods, Materials, and Applications, 103–140. https://doi.org/10.1002/9781394333363.ch04
Halko, R., Hagarová, I., Andruch, V. (2023). Innovative approaches in cloud-point extraction. Journal of Chromatography A, 1701, 464053. https://doi.org/10.1016/j.chroma.2023.464053
Doroshchuk, V. A., Gonta, N. A., Kulichenko, S. A. (2008). [Phenol-induced micellar extraction of aliphatic carboxylic acids by phases of nonionic surfactant Triton X-100]. Ukrainskii Khimicheskii Zhurnal, 74, 41–46. (In Ukrainian).
Duarte, L. de J. N., Bezerra Lopes, F. W., Araújo, E. A., Melo, R. P. F., Neto, E. L. de B., Canselier, J. P. (2024). Removing aromatic organic pollutants by cloud point extraction using biodegradable nonionic surfactants: equilibrium constants and diffusion kinetics. International Journal of Environmental Analytical Chemistry, 104(17), 5552–5573. https://doi.org/10.1080/03067319.2022.2125314
Hagarová, I., Urík, M. (2024). Cloud Point Extraction in Beverage Analysis: Innovations and Applications for Trace Elements. Beverages, 10(3), 67. https://doi.org/10.3390/beverages10030067
Sznek, B., Kupczyk, O., Czyrski, A. (2025). Cloud Point Extraction as an Environmentally Friendly Technique for Sample Preparation. Processes, 13(2), 430. https://doi.org/10.3390/pr13020430
Mandal, S., Lahiri, S. (2022). A review on extraction, preconcentration and speciation of metal ions by sustainable cloud point extraction. Microchemical Journal, 175, 107150. https://doi.org/10.1016/j.microc.2021.107150
Chatzimitakos, T., Athanasiadis, V., Mantiniotou, M., Kalompatsios, D., Bozinou, E., Giovanoudis, I., Lalas, S. I. (2023). Exploring the Feasibility of Cloud-Point Extraction for Bioactive Compound Recovery from Food Byproducts: A Review. Biomass, 3(3), 306–322. https://doi.org/10.3390/biomass3030019
Snihur, K. V., Chyzh, I. V., Shevchenko, Ye. O., Virchenko, M. O., Guzenko, O. M., Snigur, D. V. (2025). [Low-temperature analytical micellar extraction. report 3: acid-base properties of the main initiators in organized media]. Odesa National University Herald. Chemistry, 30(2(90)), 101–106. (In Ukrainian). https://doi.org/10.18524/2304-0947.2025.2(90).352384
Busev, A. I. (1972). Sintez novykh organicheskikh reagentov dlya neorganicheskogo analiza [Synthesis of new organic reagents for inorganic analysis]. Izdatelstvo MGU.
Charlot, G. (1966). Méthodes de la Chimie Analytique: Analyse Quantitative Minérale. Masson.
Lešková, M., Sklenářová, H., Bazel, Y., Chocholouš, P., Solich, P., Andruch, V. (2012). A non-extractive sequential injection method for determination of molybdenum. Talanta, 96, 185–189. https://doi.org/10.1016/j.talanta.2012.01.040
Dimitrov, A. N., Lekova, V. D., Gavazov, K. B., Boyanov, B. S. (2007). Ternary complex of molybdenum(VI) with 4-nitrocatechol and tetrazolium blue chloride and its application to extraction-spectrophotometric analysis of ferrous metallurgy products. Journal of Analytical Chemistry, 62, 122–125. https://doi.org/10.1134/s1061934807020049
Shrivas, K., Agrawal, K., Harmukh, N. (2008). Trace level determination of molybdenum in environmental and biological samples using surfactant-mediated liquid–liquid extraction. Journal of Hazardous Materials, 161, 325–329. https://doi.org/10.1016/j.jhazmat.2008.03.092
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