Ponente
Descripción
Cisplatin excreted in urine by patients undergoing chemotherapy is found in hospital wastewater matrices up to a few hundred ppb and raise environmental concerns[1,2]. The present study reports outstanding findings obtained on the removal of trace levels of cisplatin from water by using functionalized sponge.
Open-celled cellulose Metalzorb® sponge (Sponge), was functionalized by 3-Mercaptopropionic acid (MPA) through esterification. The successful functionalization was confirmed by ATR-FTIR analysis and elemental analysis. The resulting MPA@Sponge achieved 88.9 ± 0.5% removal of cisplatin from solution (235 ppb), compared to the removal of 29 ± 4% that original Sponge reached. The adsorption process of aqueous cisplatin occurs by the hydrolysis of complexes in solution and subsequent adsorption. The specific adsorption process is dominated by chelation mechanisms, in which thiol groups provide high-affinity sites for cisplatin and its derivatives to complex to. The rapid adsorption processes involving diffusion and chemisorption were well described by pseudo-second-order kinetic model. The isotherm studies suggested monolayer adsorption, consistent with the Langmuir model description. Indicated from the positive adsorption enthalpy results, the chelation of cisplatin with thiol groups was an endothermic reaction. These findings explain the mechanism of adsorption and provide ideas for the design of treatments of low-concentration cytostatic Pt wastewater.
Keywords:
Platinum cytostatics; adsorption; cisplatin; functionalization; sponge; cellulose.
References：
[1] Y. Roque-Diaz, M. Sanadar, D. Han, M. López-Mesas, M. Valiente, M. Tolazzi, A. Melchior, D. Veclani, Processes 2021, 9 (11), 1873.
[2] T.I.A. Gouveia, A.M.T. Silva, M.G. Freire, A.C.A. Sousa, A. Alves, M.S.F. Santos, Journal of Hazardous Materials 2023, 448 (January), 130883.
