Insight into photocatalyzed transformations of multiclass organic contaminants in water

Kravos, Aleksander (avtor), Cristaudo, Federico (avtor), Dal Bello, Federica (avtor), Medana, Claudio (avtor), Prosen, Helena (avtor), Calza, Paola (avtor)

This study investigates three understudied emerging contaminants: the pharmaceutical ramipril (RAM), the artificial sweetener neotame (NEO), and the herbicide cycloxydim (CYC). Laboratory simulations of natural photoinduced transformations were conducted exploring direct photolysis and TiO$_2$ photocatalysed process, followed by analysis with tandem high-resolution mass spectrometry (HRMS). The contaminants exhibited low-to-medium degree of photolysis, but rapid dissipation under photocatalysis. The assessment of transformation products (TPs) revealed several analytical challenges, particularly in peak detection and data management. The structural elucidation of the abundant TPs was achieved through multi-stage MS fragmentation studies and the transformation pathways were proposed based on the identified structures, evolution profiles, and polarities. The hydroxylation was the most common transformation for all contaminants, although each showed unique additional pathways. For instance, RAM underwent intermolecular cyclization, forming a diketopiperazine-like TP, as well as ketone formation and cleavage into low molecular mass TPs. NEO experienced ester hydrolysis, reduction, resulting in C=C bond formation, and oxidative aromatic ring-opening reactions. Lastly, CYC displayed (poly)hydroxylation or transformations of its oxime ether moiety, which underwent hydrolysis, detachment, or rearrangement, leading to oxazole TPs. The ECOSAR software was used for the prediction of toxicities of the identified TPs. In-silico toxicity prediction showed that the hydroxylated phenolic TPs of NEO and RAM, as well as certain oxazole TP isomers of CYC, have the potential to increase overall toxicity during the degradation. Overall, this paper addresses the analytical challenges and innovative methodologies for studying TPs, highlighting their growing relevance in environmental analytical chemistry.

• Jezik: Angleški jezik
• Ključne besede: transformation products, emerging organic pollutants, photocatalysis, photolysis, high-resolution mass spectrometry, non-target analysis, identification, liquid chromatography, Orbitrap
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2025
• Št. strani: 13 str.
• Številčenje: Vol. 1752, art. 465971
• PID: 20.500.12556/RUL-168743
• UDK: 547.1:544.526.5:543.544.5:543.51
• ISSN pri članku: 0021-9673
• DOI: 10.1016/j.chroma.2025.465971
• COBISS.SI-ID: 233480707
• Datum objave v RUL: 22.04.2025

Gradivo je del revije

• Naslov: Journal of chromatography
• Skrajšan naslov: J. chromatogr., A
• Založnik: Elsevier
• ISSN: 0021-9673
• COBISS.SI-ID: 6398471

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: transformacijski produkti, novodobna organska onesnaževala, fotokataliza, fotoliza, visokoločljivostna mesna spektrometrija, netarčna analiza, tekočinska kromatografija, Orbitrap