Experimental and computational study of hydrolysis and photolysis of antibiotic ceftriaxone: Degradation kinetics, pathways, and toxicity

Probing the Fate of Different Structures of Beta-Lactam Antibiotics: Hydrolysis, Mineral Capture, and Influence of Organic Matter

“…Positive ionization recorded one additional ion of significance, m/z = 261.0652, which we assigned the stoichiometry composition C 8 H 13 O 4 N 4 S + based on the natural isotope signature (Supporting Information, Appendix H). Taken collectively, we concluded that CFT-Product 1 identified in the HPLC-UV analysis is the thiotriazinone moiety (Figure E). , Thus, CFT-Product 2 was likely the remaining cleaved fragment of ceftriaxone, 3-desacetyl cefotaxime, given the high ion abundance in the m/z spectrum.…”

“…The CFT-Product 1 likely did not possess the cephem functional group with the β-lactam ring due to the absence of a peak at 264 nm . A reportedly common stable hydrolysis product of ceftriaxone is thiotriazinone (2-methyl-3-sulfanyl-1,2-dihydro-1,2,4-triazine-5,6-dione, also known as Ceftriaxone EP Impurity C), which is the six-membered ring with the attached sulfhydryl group (Figure D). ,, Two maxima at 222 nm and 271 nm were reported in the thiotriazinone spectrum, wherein the latter peak (271 nm) was shown to have a stronger absorbance than the peak at 222 nm, which aligned with the observed UV-absorption profile of CFT-Product 1 (Figure E). Therefore, we proposed that the extracted spectrum of CFT-Product 1 was from thiotriazinone, despite the spectrum being bathochromatically shifted by ∼10 nm compared with the spectrum reported previously (Figure E)this proposal was further validated by MS analysis as discussed below.…”

“…These aforementioned studies thus indicated that the degradation kinetics of β-lactam antibiotics was dependent on both the compound structure and the pH conditions. These prior studies mostly followed the disappearance of the parent antibiotic compound; little is known about the structural characteristics of the degradation compounds. ,, …”

Water-Active Titanium/Molybdenum/Mixed-Oxides: Removal Efficiency of Organic Water Pollutants by Adsorption and Photocatalysis and Toxicity Assessment

“…Appropriate aliquots were then taken and transferred into the vials for the UFLC-DAD analysis. The conditions in which the analysis was performed have been shown by Finčur et al [45] for TEM measurements, by Armaković et al [11] for MET analysis, by Ivetić et al [41] for AMI, by Ðačanin Far et al [25] for CIP, and by Abramović et al [46] for CEF measurements. Besides, conditions for QUI analysis were as follows: the mobile phase (flow rate 1.0 cm 3 /min) was a mixture of acetonitrile and 0.1% aqueous H 3 PO 4 (5:5, v/v), and the UV/Vis DAD detector was set at 224 nm (wavelength of QUI maximum absorption).…”

Removal of methyl orange using combined ZnO/Fe2O3/ZnO-Zn composite coated to the aluminium foil in the presence of simulated solar radiation

“…Thus, inexpensive and envirоnmentfriendly prоcesses fоr the complete cоnversion of pоllutants must be develоped [11]. Nоwadays, advanced оxidation prоcesses (AOPs) Photo-Fenton [12], H 2 O 2 /UV [13,14], O 3 /UV, heterogeneous photocatalysis [15,16] have attracted a grеat deal оf attentiоn owing to their very high efficiency and without generation of secondary contamination [17]. Photocatalysis, a protuberant off-shoot of AOPs, has emerged as оne оf the mоst efficient methods for the complete mineralization of toxic organic pollutants.…”