Ultrasound treated cerium oxide/tin oxide (CeO2/SnO2) nanocatalyst: A feasible approach and enhanced electrode material for sensing of anti-inflammatory drug 5-aminosalicylic acid in biological samples.

In this work, we developed cerium oxide/tin oxide (CeO₂/SnO₂) nanocatalyst with the assistance of urea by a simple sonochemical method and utilized as an efficient electrode material for electrochemical sensing of anti-inflammatory drug 5-aminosalicylic acid (Mesalamine, MES). The CeO₂/SnO₂ nanoparticles (NPs) were systematically characterized in terms of their crystal structure, morphologies, and physicochemical properties using XRD, Raman, FESEM, HR-TEM, EDX, mapping, and XPS analysis. The characterization results clearly confirmed that the prepared NPs was formed in the phase of CeO2/SnO2 without any other impurities. The electrochemical properties of CeO₂/SnO₂ NPs were investigated by EIS, CV, and DPV techniques. The CeO₂/SnO₂ NPs (9.6 μA) modified GCE demonstrated an excellent and improved electrocatalytic activity in terms of higher anodic peak current and lower peak potential when compared to bare GCE (6.7 μA) and CeO₂ NPs/GCE (8.2 μA) for the sensing of MES. The CeO₂/SnO₂ NPs/GCE shows broader linear response range and lower detection limit of 0.02-1572 μM and 0.006 μM, respectively. Moreover, other potentially interfering compounds such as a similar functional group containing biological substances and inorganic species have no interference effect towards MES sensing. In addition, the practicability of the CeO₂/SnO₂ NPs/GCE was tested by real sample analysis in commercial MES tablet, human urine, and serum samples with the appreciable recovery results.