Degradation of Metformin Hydrochloride and Glibenclamide by Several Advanced Oxidation Processes

Abstract

The degradation of metformin hydrochloride (MET) and glibenclamide (GLI), widely used anti-diabetics, was performed using an electrochemical advanced oxidation process, namely electro-Fenton, and several other Advanced Oxidation Processes (AOPs) of photocatalytic nature, like UV/H₂O₂, UV/persulfate, and UV/TiO₂. The electrochemical behavior of the drugs was first characterized by cyclic and differential pulse voltammetry. The data implied that both drugs present quasi-reversible oxidation. The effect of the applied current and the airflow in the electrogeneration of hydrogen peroxide was studied. Degradations of 60% of the initial drug were obtained for aqueous solutions of 30 mg·L⁻¹ of MET and 15 mg·L⁻¹ of GLI by using photoelectron-Fenton conditions with 1.0 A of current and a Fe²⁺ concentration of 3.5 mg·L⁻¹, although the removal of MET required 60 min of reaction while for GLI only 45 min were needed. The mineralization (organic carbon removal) percentages after 60 min of treatment were 20%and 30% for electro-Fenton and photo electro-Fenton processes, respectively. For UV/H₂O₂, UV/persulfate, and UV/TiO₂ treatments of MET solutions, the order of observed degradations was UV/PS > UV/H₂O₂ > UV/TiO₂ with maximum values of drug removal of 30% after 60 min of irradiation. This efficiency is lower than the removal observed with the electro-Fenton reaction. For GLI the order of degradation efficiency was UV/PS > UV/TiO₂ > UV/H₂O₂, with maximum values of drug removals of 99.5% after only 10 min of irradiation. This performance is clearly better that in the case of electro-Fenton or photo-electro-Fenton. The removals of the two drugs when dissolved in chemical matrices that mimic real hospital wastewaters and seawater were also studied. They showed a clear dependency on the pharmaceutical of choice. While the degradation of MET was hampered by the presence of other chemicals in the two water matrices, GLI removal was remarkable, pointing towards a possible application in real wastewaters.

Keywords

Metformin hydrochloride / Glibenclamide / Electro-Fenton / UV/H₂O₂ / UV/persulfate / UV/TiO₂ / AOPs

Ackn+owledgments

This Special Issue honours David Ollis, a key figure in the area of Photocatalysis. The paper’s corresponding author had the great chance of expending two years in Dave’s laboratory and getting to know him well. He was always, and still is, an academic and scientific reference, both in the fields of Photocatalysis and Biochemical Engineering. He provided important guidelines for moving forward and his didactic and constructive criticism distinguished him as a superior scholar and teacher. But above all, he was an extraordinary person from a human perspective. We will miss you Dave!

Au+thor Contri+butions

Conceptualization: L.M.B. and J.P. Experimental development of electroFenton experiments: I.A.A.-L. Experimental development of Fenton and photo-Fenton experiments: G.H.-M. and F.G.-R. Discussion of the results: G.H.-M., F.G.-R., L.M.B. and J.P. Writing: J.P. Funding Acquisition: G.H.-M., F.G.-R., L.M.B. and J.P.

Eth+ics State+ment

Not applicable.

Informed Consent Sta+tement

Not applicable.

Data Availa+bility State+ment

Not applicable.

Fu+nding

The authors want to acknowledge the financial support received from CONACYT, Mexico, from the Spanish Ministry of Science and Innovation for funding the AQUAENAGRI (PID2021-126400OB-C33) project, and from the Institución Universitaria Colegio Mayor de Antioquia through project FAI36.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

[1] FMD, A.C. Encuesta Nacional de Salud y Nutrición 2012. 2014. Available online: http://www.fmdiabetes.org/fmd/pag/diabetes_numeros.php (accessed on 2 September 2014).

[2] Pinel J, Naboulet C, Weiss F, Henkens M, Grouzard V. Essential Drugs. Practical Guidelines. Medecins Sans Frontiers. ISBN 2906498912. 2013. Available online: https://bookmemoryblog.wordpress.com/wp-content/uploads/2014/07/14-essential-drugs1.pdf (accessed on 5 February 2025).

[3] Glucovance (Glyburide and Metformin HCl) Tablets. FDA Guidance Documents. 2018. Available online: https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/021178s018lbl.pdf (accessed on 5 February 2025).

[4] Rivera J, Sánchez M, Ferro MA, Prados G, Ocampo R. Pharmaceuticals as emerging contaminants and their removal from water. A review. Chemosphere 2013, 93, 1268-1287.

[5] Comninellis C, Kapalka A, Malato S, Parsons SA, Poulios I, Mantzavinos D. Advanced oxidation processes for water treatment: Advances and trends for R&D. J. Chem. Technol. Biotechnol. 2008, 83, 769-776. doi:10.1002/jctb.1873.

[6] Deng Y, Zhao R. Advanced Oxidation Processes (AOPs) in Wastewater Treatment. Curr. Pollut. Rep. 2015, 1, 167-176. doi:10.1007/s40726-015-0015-z.

[7] Fernández MA, Iglesias O, Pazos M, Sanromán A. Application of electro-Fenton technology to remediation of polluted effluents by self-sustaining process. Sci. World J. 2014, 2014, 801870.

[8] Brillas E, Sirés I, Oturan MA. Electro-Fenton process and related electrochemical technologies based on Fenton’s reaction chemistry. Chem. Rev. 2009, 109, 6570-6631.

[9] Neamtu M, Grandjean D, Sienkiewicz A, Le-Faucheurd S, Slaveykovad V, Velez-Colmenares JJ, et al. Degradation of eight relevant micropollutants in different water matrices by neutral photo-Fenton process under UV₂₅₄ and simulated solar light irradiation-A comparative study. Appl. Catal. B Environ. 2014, 158-159, 30-37.

[10] Litter M. Introduction to photochemical advanced oxidation processes for water treatment. In The Handbook of Environmental Chemistry, 2, L:13 Environmental Photochemistry Part II;Bahnemann D, Boule P, Eds.; Springer: New York, NY, USA, 2005. ISBN 3540002693.

[11] Gao YQ, Gao NY, Deng Y, Yang YQ, Ma Y. Ultraviolet (UV) light-activated persulfate oxidation of sulfamethazine in water. Chem. Eng. J. 2012, 195, 248-253. doi:10.1016/j.cej.2012.04.084.

[12] Rengifo-Herrera JA, Pulgarin C. Why five decades of massive research on heterogeneous photocatalysis, especially on TiO₂, has not yet driven to water disinfection and detoxification applications? Critical review of drawbacks and challenges. Chem. Eng. J. 2023, 477, 146875. doi:10.1016/j.cej.2023.146875.

[13] Fujishima A, Zhang X, Tryk DA. Heterogeneous photocatalysis: from water photolysis to applications in environmental cleanup. Int. J. Hydrogen Energy 2007, 32, 2664-2672. doi:10.1016/j.ijhydene.2006.09.009.

[14] Possanzini M, Di Palo V. Improved titanium method for determination of atmospheric H₂O₂. Anal. Chim. Acta 1995, 315, 225-230. doi:10.1016/0003-2670(95)00255-X.

[15] Bard AJ, Faulkner LR, White HS. Electrochemical Methods: Fundamentals and Applications; Wiley: Hoboken, NJ, USA, 2022. ISBN 10: 1119334063.

[16] Pignatello JJ, Oliveros E, MacKay A. Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry. Crit. Rev. Environ. Sci. Technol. 2007, 36, 1-84. doi:10.1080/10643380500326564.

[17] Torrades F, Pérez M, Mansilla HD, Peral J. Experimental design of Fenton and photo-Fenton reactions for the treatment of cellulose bleaching effluents. Chemosphere 2003, 53, 1211-1220. doi:10.1016/S0045-6535(03)00579-4.

[18] He H, Zhou Z. Electro-Fenton process for water and wastewater treatment. Electro-Fenton process for water and wastewater treatment. Crit. Rev. Environ. Sci. Technol. 2017, 47, 2100-2131. doi:10.1080/10643389.2017.1405673.

[19] Kang J, Irmak S, Wilkins M. Conversion of lignin into renewable carboxylic acid compounds by advanced oxidation processes. Renew. Energy 2019, 135, 951-962. doi:10.1016/j.renene.2018.12.076.

[20] Parra-Marfil A, López-Ramón MV, Aguilar-Aguilar A, García-Silva IA, Rosales-Mendoza S, Romero-Cano LA, et al. Electro-Fenton process for water and wastewater treatment. Electro-Fenton process for water and wastewater treatment. Crit. Rev. Environ. Sci. Technol. 2017, 47, 2100-2131. doi:10.1080/10643389.2017.1405673.

[21] Calzadilla MASW, Vidal J, Brillas E, Salazar-González R. Contaminants of emerging concern: Occurrence, analytical techniques, and removal with electrochemical advanced oxidation processes with special emphasis in Latin America. Environ. Pollut. 2024, 345, 123397. doi:10.1016/j.envpol.2024.123397.

[22] Aguirre AR, Reina AC, Peral J, Colon G, Malato S. Catalysts and Photoreactors for Photocatalytic Solar Hydrogen Production: Fundamentals and Recent Developments at Pilot Scale. In Photocatalytic Hydrogen Production for Sustainable Energy; Puga A, Ed.; Wiley: Hoboken, NJ, USA, 2023. ISBN 978-3-527-83541-6.

[23] Maldonado MI, López-Martín A, Colón G, Peral J, Martínez-Costa JI, Malato S. Solar pilot plant scale hydrogen generation by irradiation of Cu/TiO₂ composites in presence of sacrificial electron donors. App. Catal. B Environ. 2018, 229, 15-23. doi:10.1016/j.apcatb.2018.02.005.

[24] Mahbub P, Duke M. Scalability of advanced oxidation processes (AOPs) in industrial applications: A review. J. Environ. Manag. 2023, 345, 118861. doi:10.1016/j.jenvman.2023.118861.

[25] Gimenez J, Esplugas S, Malato S, Peral J. Economic Assessment and Possible Industrial Application of a (Photo)catalytic Process: A Case Study. In Heterogeneous Photocatalysis. Relationships with Heterogeneous Catalysis and Perspectives; Marcı G, Palmisano L, Eds.; Elsevier: Amsterdam, The Netherlands, 2019, ISBN: 978-0-444-64015-4. doi:10.1016/B978-0-444-64015-4.00008-0.

[26] Hübner U, Rüting S, Spahr S, Lutze H, Gernjak W, Wenk J. Advanced oxidation processes for water and wastewater treatment—Guidance for systematic future research. Heliyon 2024, 10, e30402. doi:10.1016/j.heliyon.2024.e30402.

[27] Gahrouei AE, Vakili S, Zandifar A, Pourebrahimi S. From wastewater to clean water: Recent advances on the removal of metronidazole, ciprofloxacin, and sulfamethoxazole antibiotics from water through adsorption and advanced oxidation processes (AOPs). Environ. Res. 2024, 252, 119029. doi:10.1016/j.envres.2024.119029.

[28] Moradi A, Kazemeini M, Hosseinpour V, Pourebrahimi S. Efficient degradation of naproxen in wastewater using Ag-deposited ZnO nanoparticles anchored on a house-of-cards-like MFI-type zeolite: Preparation and physicochemical evaluations of the photocatalyst. J. Water Proc. Eng. 2024, 60, 105155. doi:10.1016/j.jwpe.2024.105155.

[29] Malato S, Maldonado MI, Fernandez-Ibañez P, Oller I, Polo I, Sanchez-Moreno R. Decontamination and disinfection of water by solar photocatalysis: the pilot plants of the Plataforma Solar de Almeria. Mater. Sci. Semicond. Proc. 2016, 42, 15-23. doi:10.1016/j.mssp.2015.07.017.