Selective inhibition of P450 enzymes is the key to block the conversion of environmental procarcinogens to their carcinogenic metabolites in both animals and humans. To discover highly potent and selective inhibitors of P450s 1A1, 1A2, and 1B1, as well as to investigate active site cavities of these enzymes, 14 novel flavone derivatives were prepared as chemical probes. Fluorimetric enzyme inhibition assays were used to determine the inhibitory activities of these probes towards P450s 1A1, 1A2, 1B1, 2A6, and 2B1. A highly selective P450 1B1 inhibitor, 5-hydroxy-4′-propargyloxyflavone (5H4′FPE) was discovered. Some tested compounds also showed selectivity between P450s 1A1 and 1A2. Alpha-naphthoflavone-like and 5-hydroxyflavone derivatives preferentially inhibited P450 1A2, while beta-naphthoflavone-like flavone derivatives showed selective inhibition of P450 1A1. On the basis of structural analysis, the active site cavity models of P450 enzymes 1A1 and 1A2 were generated, demonstrating a planar long strip cavity and a planar triangular cavity, respectively.

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Nanostructure transition metal oxides (MO-type M = Fe, Co, Ni, Cu, . . . ) with rock-salt structure are promising anode materials to be used in lithium ion batteries, when compared to conventional graphite anodes due to their superior Li- ions storage capability. NiO nanostructures were successfully grown onto stainless steel 304 substrates using a low pressure chemical vapor deposition process at 600°C and characterize their morphology-dependent electrochemical behavior at room temperature. Structure and elemental analysis of the NiO nanostructures were confirmed using X-ray diffraction and EDS. Oxidation states and elemental analysis was confirmed with XPS analysis. The electrochemical performances of the NiO electrode were studied using cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) techniques in LiPF6 with in 1:1:1: EC, DMC, and DC electrolyte in the voltage range of 0.1 - 4.0 V at a constant current of 0.1 mA vs Li/Li+. Solid electrolyte interface (SEI) appeared at the first cycle and disappeared in the subsequent cycles, however two oxidation peaks were observed at 1.63 V and 2.23 V which have been assigned to the depletion of the electrolyte and oxidation of Ni+2, respectively. NiO nanostructures have shown a first-cycle capacity of about 782 mAh/g, which is more than the expected theoretical capacity of 718 mAh/g after the conversion reaction. The origin of the excess capacity is due to the Pseudo-capacitive nature of the materials at low voltages and interfacial charge storage. A loss in capacity in the second discharge is observed which is due to loss of materials. The electrochemical properties of the as synthesized NiO nanostructures were investigated to determine their suitability as anode materials for lithium-ion batteries.