Functionalized Electrochemical Aptasensor for Sensing of Ochratoxin A in Cereals Supported by <i>in Silico</i> Adsorption Studies

An aptamer to selectively detect ochratoxin A (OTA) in cereals was developed using silver nanoparticles (AgNPs) combination with reduced graphene oxide (rGO). As a result of characterization experiments conducted this study, AgNPs were confirmed be polydisperse. The electrocatalytic activity achieved by immobilizing OTA-bovine serum albumin (OTA-BSA) on the rGO/AgNPs substrate. On basis experimental conditions optimized for aptasensor, linear dynamic range 0.002–0.016 mg/L and threshold 7 × 10–4 (S/N = 3). At an atomic molecular level, computational adsorption studies revealed how OTA-BSA interacts composite substrates spatial scale. Calculations density functional theory (DFT) that OTA has energy gap ?4.5 eV, which implies strong tendency operate as electron donor. use modeling also provided structural information about interactions between biomolecules nanostructures, well electronic properties OTA. electrochemically modified aptasensor showed good agreement computed energies current responses. In addition its excellent reproducibility stability, proposed demonstrated applicability food industry.