具有抗多种活性氧酶功能的金属卟啉的研究—钌卟啉仿酶活性测试

二价金属钌卟啉[Ru^Ⅱ(4-Cl-TPP)(CO)](1),[Ru^Ⅱ(4-MeO-TPP)(CO)](2),[Ru^Ⅱ(C,4,5-MeO-TPP)(CO)](3)和六价金属钌卟啉[Ru^Ⅵ（4Cl-TPP)(O)2](4),[Ru^Ⅵ(4-MeO-TPP)(O)2](5),[Ru^Ⅵ(3,4,5-MeO-TPP)(O)2](6)被合成,配合物1－6作为超氧化物歧化酶（SOD）和过氧化氢酶（CAT）功能模拟酶被测试,核黄素－蛋胺酸光照法证实,钌啉啉在不同浓度范围内有催化歧化O^.-2的作用,分光光度法证实能催化H2O2分解,用小鼠肝匀浆法测度试结果表明：金属钌啉具有良好的抗脂质过氧化作用,提出了金属钌卟啉在催化歧化超氧阴离子自由基（O^.-2)和催化分解过氧化氢（H2O2）协同过程中的可能机理,并讨论了卟啉环上不同取代基对催化活性的影响。     

喹诺酮类药物与铜锌超氧化物歧化酶的相互作用及其对酶活性的影响

利用紫外-可见吸收光谱和荧光光谱,在pH=7.4的生理条件下,研究了喹诺酮类药物(依诺沙星、环丙沙星和诺氟沙星)与铜锌超氧化物歧化酶(CuZnSOD)的相互作用。喹诺酮类药物能使CuZnSOD的荧光发生猝灭,其猝灭机理为静态猝灭。通过实验计算了不同温度下喹诺酮类药物与CuZnSOD的结合常数和结合点数。依据Frster非辐射能量转移理论,得到供体与受体间的距离。根据热力学参数确定了它们之间的主要作用力类型是静电引力。进一步证实了活体动物兔子注射环丙沙星后,血液中铜锌超氧化物歧化酶活性显著降低。     

Poly-5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin as a material for photovoltaic devices

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超氧化物歧化酶活力测定曲线的线性化研究

用从猪红细胞制备的ＣｕＺｎ－ＳＯＤ，采用黄嘌呤氧化酶－ＮＢＴ法、改良的邻苯三酚自氧化法、经典的邻苯三酚自氧化法、ＮＢＴ光还原法及肾上腺素自氧化法等５种方法，得到５条典型的酶活力测定曲线，寻找到２种测活曲线直线化的数学处理方法，使ＳＯＤ测活工作变得更简便     

A Chiral Ligand Assembly That Confers One‐Electron O2 Reduction Activity for a Cu2+‐Selective Metallohydrogel

The design of functional metallohydrogels is attractive but challenging. A rational approach is introduced for designing functional metallohydrogels using chiral ligands, a phenylalanine derivative with a pyridyl group (l /d ‐PF). Intriguingly, the as‐prepared metallohydrogel exhibits excellent O₂ binding and activating properties. Insights into the O₂ binding pathway reveals the presence of a novel [(l +d )‐PF‐Cu³⁺‐O₂^?] species, which can efficiently reduce ferric cytochrome c with the reactive O₂^? by receiving an electron from reductant ascorbic acid. This study provides helpful instructions for developing new artificial systems with specific functions through the effective combination of chiral ligands with metal ions.     

Modulating the Folding Landscape of Superoxide Dismutase 1 with Targeted Molecular Binders

Amyotrophic lateral sclerosis, or Lou Gehrig's disease, is characterized by motor neuron death, with average survival times of two to five years. One cause of this disease is the misfolding of superoxide dismutase 1 (SOD1), a phenomenon influenced by point mutations spanning the protein. Herein, we used an epitope‐specific high‐throughput screen to identify a peptide ligand that stabilizes the SOD1 native conformation and accelerates its folding by a factor of 2.5. This strategy may be useful for fundamental studies of protein energy landscapes as well as designing new classes of therapeutics.     

The Long‐Term Stability of KO2 in K‐O2 Batteries

The rechargeable K‐O₂ battery is recognized as a promising energy storage solution owing to its large energy density, low overpotential, and high coulombic efficiency based on the single‐electron redox chemistry of potassium superoxide. However, the reactivity and long‐term stability of potassium superoxide remains ambiguous in K‐O₂ batteries. Parasitic reactions are explored and the use of ion chromatography to quantify trace amounts of side products is demonstrated. Both quantitative titrations and differential electrochemical mass spectrometry confirm the highly reversible single‐electron transfer process, with 98 % capacity attributed to the formation and decomposition of KO₂. In contrast to the Na‐O₂ counterparts, remarkable shelf‐life is demonstrated for K‐O₂ batteries owing to the thermodynamic and kinetic stability of KO₂, which prevents the spontaneous disproportionation to peroxide. This work sheds light on the reversible electrochemical process of K⁺+e^?+O₂?KO₂.     

壳聚糖固定化N-亚水杨基甘氨酸锌Schiff碱配合物的研究

利用天然高分子聚合物壳聚糖的轴向配位能力, 首次合成了壳聚糖-N-亚水杨基甘氨酸Schiff碱锌配合物, 通过元素分析、紫外吸收光谱、红外吸收光谱和热分析等方法对配体及配合物进行了表征, 推测了配合物的结构组成. 以Pyrogallol-NBT比色法测定了合成配合物对超氧阴离子自由基的清除能力. 结果表明, 壳聚糖固定化N-亚水杨基甘氨酸锌Schiff配合物对超氧阴离子自由基的清除能力与水杨醛锌Schiff配合物相比大致一样, 但毒性较小.     

Biosensors as a tool for the antioxidant status evaluation

Antioxidants are one of the main ingredients that protect food attributes by preventing oxidation that occurs during processing, distribution and end preparation of food. Physiological antioxidant protection involves a variety of chemical system of endogenous and exogenous origin in a multiplicity of pathways. Associate to this, researches have been directed in the development of methods as biosensors that can characterize antioxidants capable of removing harmful radicals in living organisms in an adequate way. Biosensors have represented a broad area of technology useful for environmental, food monitoring, clinical applications and can represent a good alternative method to evaluate the antioxidant status.The demonstration of the highlighted current application of biosensor as a potential tool to evaluate the antioxidant status is the main aim of this review.     

Superoxide Anion Radical Scavenging Ability of Quaternary Ammonium Salt of Chitosan

A series of N-alky1 or N-ary1 chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes.