title: Determination of 6-mercaptopurine in the presence of uric acid using modified multiwall carbon nanotubes-TiO2 as a voltammetric sensor.
abstract: In this work, a multiwall carbon nanotubes modified electrode (prepared by incorporating TiO(2) nanoparticles with p-aminophenol as a mediator) was used as voltammetric sensor for the determination of 6-mercaptopurine (6-MP) in the presence of uric acid (UA). The voltammograms of 6-MP and UA in a mixture can be separated from each other by differential pulse voltammetry with a potential difference of 380 mV at a scan rate of 10 mV s(-1). These conditions are sufficient to allow for the determination of 6-MP and UA both individually and simultaneously. The electrocatalytic currents increase linearly with 6-MP concentration in the ranges of 0.09-350 µmol L(-1) (two linear segments with different slopes). The detection limit for 6-MP was 0.065 µmol L(-1) . The RSD% for 1.0 and 15.0 µmol L(-1) 6-MP were 0.7%, and 1.2%, respectively. The kinetic parameters of the system were determined using electrochemical approaches. The method was successfully applied for the determination of 6-MP in drug sample, and 6-MP plus UA in urine samples.
authors.affiliation: Department of Chemistry, Isfahan University of Technology, Iran. Ensafi@cc.iut.ac.ir
authors.forename: Ali A
authors.initials: AA
authors.lastname: Ensafi
authors.forename: H
authors.initials: H
authors.lastname: Karimi-Maleh
mesh_terms: D002384:Catalysis; D058266:Dielectric Spectroscopy; D016903:Drug Monitoring / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004867:Equipment Design; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D057230:Limit of Detection; D016014:Linear Models; D015122:Mercaptopurine / Q000652:urine*; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D011199:Potentiometry / Q000295:instrumentation*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014527:Uric Acid / Q000652:urine*
chemical_list: D037742:Nanotubes, Carbon; C009495:titanium dioxide; D014527:Uric Acid; D014025:Titanium; D015122:Mercaptopurine