A Novel Sensor of Quinazolin Derivative Self-Assembled Monolayers over Silver Nanoparticles for the Determination of Hydroxylamine

摘要

The electrochemical study of a quinazolin silver nanoparticles抦odified glassy carbon electrode(QMSNPs扜CE) as well as its efficacy for electrocatalytic oxidation of hydroxylaminein presence ofsuch self抋ssembled monolayer (SAM) modified electrodeis described. The QMSNPs扜CEdemonstrated a highly catalytic activity in hydroxylamine oxidation. Results indicated thathydroxylamine peak potential at QMSNPs扜CE shifted for 170 and 260 mV to negative valuescompared to quinazolin抦odified glassy carbon electrode (QMGCE) and silver nanoparticles coatedglassy carbon electrode (SNPs扜CE) respectively. It was also shown that a combination of SNPs andmodifier definitely improves the characteristics of hydroxylamine oxidation. The surface chargetransfer rate constant, ks, and the charge transfer coefficient, , for electron transfer between GCE and electrodeposited quinazolin modified GCE were calculated as 39.51.1 s and 0.53 respectively atpH=7.The electron transfer coefficient, , and the heterogeneous rate constant, k for the oxidation ofhydroxylamine at QMSNPs扜CE were also determined by cyclic voltammetry measurements.Furthermore, amperometric detection of hydroxylamine was carried out at 270 mV in a 0.1 Mphosphate buffer solution (pH 7.0) resulting in two linear response ranges of 1.001.5 M and101.5410.8 M and the limit of detection of 0.38 M. Moreover, QMSNPs扜CE was successfullyused to determine hydroxylamine in various water samples.