| Flavones have attracted great interests due to their anti-oxidative, anti-free-radical, cancer-prevent and cancer-resistant activities. In this paper, the free radical scavenging activities of several natural flavones were studied by electrochemical method and the interactions between luteolin , luteolin-O-β-D-glucoside and bovine serum albumin( BSA ) were studied by electrochemical method, UV absorption and NMR spectroscopy. An electro-analytical method determining flavones through an ensemble of carbon fibers ultra-microelectrode modified with carbon nanotubes was discussed. The main contents are as follows:Chapter 1. Anti-free-radical activities of natural flavones isolated from some Chinese Herbal MedicineThe free radical scavenging activities of several natural flavones named 5-hydroxy-7,4′-dimethoxyflavanone, 5,4′-dihydroxy-7-methoxyflavanone, 5,3′,4′-trihydroxy-7-methoxyflavanone, 5,3′,4′-trihydroxy-7-flavanoneglycoside, 3,5,7-trihydroxy-4′-methoxyflavanone, 5,3′,4′-trihydroxy-7-methoxyflavanone, 5,3′,4′-trihydroxy-7-flavanoneglycoside, 5,3′,4′-trihydroxy-7-methoxyflavone, and 5,7,3′,6′-tetrahydroxy-6,4′-dimethoxyflavone were investigated by single-sweep oscillopolarography, differential pulse voltammetry and cyclic voltammetry. Their scavenging activities to superoxide anion radicals and DPPH radicals were studied.Chapter 2. Investigation on the interaction of luteolin and luteolin-7-O-β-D- glucoside with bovine serum albumin3′,4′-adjacent hydroxyl of luteolin and luteolin-7-O-β-D-glucoside were studied using cyclic voltammetry method. The results showed that the inactive electrochemical supramolecular structures were formed in BSA-luteolin and BSA-luteolin-7-O-β-D-glucoside complexes. The binding constants are 9.33×106 L·mol-1, 1.12×106 L·mol-1 and the numbers of binding site are 1.32 and 1.10, respectively.Chapter 3. Application of carbon nanotube modified carbon fibers ultra-microelectrode on determination of luteolinIn this chapter an ensemble of carbon fibers ultra-microelectrode modified by carbon nanotubes were constructed. The electrochemical characteristics of the EUME-CNT were investigated by cyclic voltammogram method and an electro-analytical method determining luteolin was founded through optimizing detection parameters. The detection limit was found to be 4×10-7 mol·L-1 and the linear calibration plots were obtained for the oxidation peak current in a range from 6×10-7 to 1×10-5 mol·L-1.
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