title: Direct amperometric determination of lactate at a carbon fiber bundle microdisk electrode by capillary zone electrophoresis.
abstract: Capillary zone electrophoresis was employed for the determination of lactate using end-column amperometric detection at a carbon fiber bundle microdisk electrode. The optimum conditions of separation and detection are 3.6 x 10(-3) mol/l Na(2)HPO(4)-1.4 x 10(-3) mol/l NaH(2)PO (pH 7.2) for the buffer solution, 18 kV for the separation voltage and 1.60 V versus the saturated calomel electrode for the detection potential. The limit of detection is 7.6 x 10(-7) mol/l or 1.7 fmol (S/N=3) and the linear range is 1.7 x 10(-6)-8.2 x 10(-4) mol/l for the injection voltage of 6 kV and injection time of 5 s. The RSD is 1.8% for the migration time and 3.3% for the electrophoretic peak current. The method was applied to the determination of lactate in human saliva. The recovery of the method is between 95 and 109%.
authors.affiliation: School of Chemistry and Chemical Engineering, and State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Dong
authors.forename: Rui
authors.initials: R
authors.lastname: Dong
authors.forename: Mingliang
authors.initials: M
authors.lastname: Jin
authors.forename: Wenrui
authors.initials: W
authors.lastname: Jin
mesh_terms: D002244:Carbon; D004566:Electrodes; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D019344:Lactic Acid / Q000032:analysis*; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry; D012680:Sensitivity and Specificity
chemical_list: D019344:Lactic Acid; D002244:Carbon