Study on the catalytic reaction of β-CD-hemin using 2,3,4-trichlorophenol as substrate and analytic application

The catalytic activity of various mimetic enzymes instead of the peroxidase have been investigated by 4-aminoantipyrine (4-AAP) and 2,3,4-trichlorophenol (TCP) to form a dye utilizing hydrogen peroxide as hydrogen acceptor. The different Chlorophenolic derivatives, which act as a substrate in beta -CD-hemin-H2O2-4-AAP catalytic reaction, have been systematically studied. Meanwhile, the relationship of structure-effect for the beta -CD-hemin as catalyst, and chlorphenols as substrate has been respectively discussed. The mechanism of catalytic reaction has been investigated. The results showed that beta -CD-hemin was the best mimetic enzyme for peroxidase among those tested and TCP was a good substrate for the determination of hydrogen peroxide with beta -CD-hemin. The method for the determination of hydrogen peroxide was proposed using 4-AAP-TCP system with beta -CD-hemin as catalyst. A linear calibration graph was obtained over the H2O2 concentration of 4.8x10(-8)-7.7x10(-5) M, and the relative standard deviation at a H2O2 concentration of 2.8x10(-5) M was 2.5%. The apparent molar absorptivity of the chromogenic reaction for H2O2 was 1.54x10(4) L(.)mol(-1.)cm(-1). Satisfactory results were obtained in the determination of H2O2 in synthetic samples by this method. Also, the method was coupled with the glucose oxidation reaction to determination glucose in human serum.