Study on the kinetics of keto-enol tautomerism of p-hydroxyphenylpyruvic acid using capillary electrophoresis.
The kinetics of keto-enol tautomerism of p-hydroxyphenylpyruvic acid (pHPP) as a model of alpha-carbonyl compounds in aqueous solution at room temperature (25 degrees C) was first investigated by capillary electrophoresis with UV detection at 200 nm. The two tautomers could be separated and detected within 3 min. Since the ketonization of enolic pHPP varied with the buffer composition and buffer pH, the kinetics of pHPP was studied under different conditions, and relevant distributing fractions of enolic pHPP, ketonization rate constants and half-life were determined. In addition, beta-CD played an important part in the separation of the two tautomers, thus, the interaction between pHPP and beta-CD was also investigated by electrochemical techniques.
Huang
Lu
L
Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety (Fuzhou University), Fuzhou, Fujian 350002, China.
Huang
Ying
Y
Chi
Yuwu
Y
Lin
Jinming
J
Yu
Lishuang
L
Xu
Liangjun
L
Chen
Guonan
G
D019075:Electrophoresis, Capillary / Q000379:methods*; D007536:Isomerism; D007700:Kinetics; D010667:Phenylpyruvic Acids / Q000737:chemistry*; D015203:Reproducibility of Results; D047392:beta-Cyclodextrins / Q000737:chemistry
D010667:Phenylpyruvic Acids; D047392:beta-Cyclodextrins; C010590:4-hydroxyphenylpyruvic acid; C031215:betadex