TITLE:
High Resolution Mass Spectrometry Elucidation of Captopril’s Ozonation and Chlorination By-Products
AUTHORS:
Frederico Jehár Oliveira Quintão, Geraldo Célio Brandão, Silvana de Queiroz Silva, Sérgio Francisco Aquino, Robson José de Cássia Franco Afonso
KEYWORDS:
Chlorination, Ozonation, Captopril, High-Resolution Mass Spectrometry, Liquid Chromatography, Characterization of By-Products, MTT Assay
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.8 No.4,
April
30,
2017
ABSTRACT: The article evaluated the degradation of the captopril in aqueous solution after ozonation and chlorination. The process was continuously monitored focusing on the identification, mass spectrometry and elucidation of its by-products by applying direct infusion and high performance liquid chromatography, electrospray ionization high resolution mass spectrometry, in the negative ion mode. The cytotoxicity of its by-products solutions were evaluated with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. It was observed through that after 30 min of ozonation and chlorination, there was complete oxidation of captopril, i.e., 100% removal efficiency. At these conditions, the rate of mineralization, by total organic carbon, was only 7.63% for ozonation and 6.40% for chlorination, evidencing the formation of degradation by-products. Ten captopril by-products were identified and their respective chemical structures elucidations are proposed. The treated samples and their by-products were nontoxic to HepG2 cells by MTT assay.