Comet-like Co-MOF with TiO2 nanoparticles decorated used to efficiently activate peroxymonosulfate for larotrectinib degradation through radical and non-radical pathways

Removal of emerging contaminants has drawn great concern due to their potential high risk to eco-environment system and human health. In this study, an emerging and broad-spectrum anticancer pharmaceutical, larotrectinib (LOXO), was focused on to achieve its degradation in water. A heterogenous peroxymonosulfate (PMS) activation system was constructed by using a comet-like Co-based metal-organic framework (Co-MOF) with TiO2 nanoparticles decorated. The optimized material (TiO2/Co-MOF1) showed high PMS activation efficiency, and thus 90.1 % of LOXO could be quickly degraded within 10 min. Scavenger quenching tests and electron paramagnetic resonance (EPR) analysis indicated that both radicals (center dot OH and SO4 center dot-) and non-radical species (1O2) contributed to LOXO degradation. The two main components of Co-MOF and TiO2 nanoparticles in the composite showed a synergetic effect on PMS activation: Co-MOF offered coordination cobalt for PMS activation, while TiO2 provided abundant -OH groups for interface complexation to promote the electron transfer. In addition, 1O2 originates from directional conversion of center dot O2- after PMS activation at the material's surface. Moreover, density functional theory (DFT) calculation suggests that the atoms in LOXO with high Fukui index (f -) representing electrophilic attack are the reactive sites. Toxicity analysis based on quantitative structure-activity relationship (QSAR) verifies the reduced toxicity of degraded intermediates/products. This work proposed an available technology to efficiently activate PMS for anticancer drugs degradation through both radical and non-radical pathways in wastewater.