Studies On The Feton Reaction By Manganese With Fluorimetry Assay Of Aromatic Hydroxylation

In this study, RP-HPLC with fluorescence detection and Fluorescence spec trum(excitation 277nm and emission 306nm) was used to detect hydroxyl radic al generated by Cu(â…¡)-H₂O₂ (Fenton like reaction) system, using a fluorescenc e probe, L-phenylalanine, which could be converted to highly fluorescent L-tyr osine in the presence of -OH. Before and after reaction, the variety of fluores cence intensity reflected the generation of OH. The data of two methods wer e compared. By this, we can conclude that the result of two methods have qu ite coherence. Furthermore, the fluorescence spectrum is a more convenient m ethod. But the fluorescence intensitydetected by fluorescence spectrum reflectedall fluorescent components in the system.Other .OH generation system, such as Fe(â…¡)—H₂O₂ or phenanthroline- Cu(â…¡) coordinate—H₂O₂, influenced the a ccuracy of the result. So the method applied to detect OH by FS is confined.On the other hand, RP-HPLC with fluorescence detectionwas used to detect hydroxyl radical generated by Fenton like reaction systemparticipatated by seve n 3d-transition metal-ions,using a fluorescence probe,L-phenylalanine,which coul d be converted to highly fluorescent L-tyrosine in the generation of OH. the variety of fluorescence intensity reflected the generation of OH.The experiment al results indicated that ability of Cr(â…¢),Fe(â…¡),Co(â…¡),Cu(â…¡),Pb( â…¡) to produce ? OH is relatively strong , but the ability of Cd( â…¡) and Ni( â…¡) is poor. The intensityof fluorescence in the systems could be inhibited obviously by mannite andde sferrioxamine(DFO),which proved OH was cleard. We used the UV spectrome ter and gotthe same results. Aromatic hydroxylation was more effective and re liable. So this sensitive method can be applied to study the hydroxyl radical and hydroxyl radicalscavenger.Based on the dispute whether Mn( II )and Mn(III) inhibit or accelerate the production of OH, the article studied on the Fenton-like reaction which Mn(II) and Mn(III) participated in with the method of electron spin resonance,, aromatic hydroxylation and Agrose gel electropHoresis. Results indicated that Mn(II) and Mn(III) inhibit the production of -OH when the ionic concentration is higher , but accelerate obviously when it is lower.And the OH producted in the Fenton-like system of Mn( II )and Mn(III) was inhibited obviously by scavengerAt the same time the results indicated that Mn(II) inhibited the production of -OH in the Fenton system when the ionic concentration is higher and accelerate when it is lower. This research has made the preliminary explanation to the function mechanisms of Mn( II) and Mn(III) participating in Fenton-like reaction,and it has provided experiment and theoretical basic about the dispute whether Mn( II) and Mn(III) inhibit or accelerate the production of OH.