title: Catalytic spectrophotometric determination of ascorbic acid in tea drink with 1,5-bis(p-hydroxybenzaldene)thiocarbohydrazone as the substrate for horseradish peroxidase.
abstract: 1,5-bis(p-Hydroxybenzaldene)thiocarbohydrazone (BHBTZ) had been synthesized and used as a new kind of substrate for horseradish peroxidase (HRP). The experiment results showed that ascorbic acid (AsA) had strongly inhibiting effect on the BHBTZ-H(2)O(2)-HRP reaction system, so AsA had been spectrophotomericly determined as the inhibitor by enzymatic inhibition method. Under experimental conditions, the linear relationship between DeltaA(386) and AsA concentration was in the range of 0.82-18.0 microg ml(-1) with a detection limit of 0.245 microg ml(-1). The effect of interferences on AsA determination was investigated. The proposed method was successfully applied to the determination of AsA in tea drink.
authors.affiliation: Department of Chemistry, Shandong Normal University, Jinan, 250014, People's Republic of China. tangb@sdnu.edu.cn
authors.forename: Bo
authors.initials: B
authors.lastname: Tang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Du
authors.forename: Jie-Chao
authors.initials: JC
authors.lastname: Ge
authors.forename: Zhen-Zhen
authors.initials: ZZ
authors.lastname: Chen
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis*; D002384:Catalysis; D006735:Horseradish Peroxidase / Q000378:metabolism*; D006835:Hydrazones; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D012680:Sensitivity and Specificity; D013053:Spectrophotometry / Q000379:methods*; D013662:Tea / Q000737:chemistry*
chemical_list: C477017:1,5-bis(p-Hydroxybenzaldene)thiocarbohydrazone; D006835:Hydrazones; D007202:Indicators and Reagents; D013662:Tea; D006735:Horseradish Peroxidase; D001205:Ascorbic Acid