荧光素与阴离子表面活性剂的荧光性质研究

研究了荧光素（Fluorescein）与阴离子表面活性剂（Anioni surfactant）十二烷基苯磺酸钠（Sodiun dodecyl benzenesulfonate）、十二烷基磺酸钠（Sodium laurylsulfonate）、十二烷基硫酸钠（Sodiumdodecyl sulphate）的荧光性质,探讨了实验条件对荧光素与阴离子表面活性剂荧光性质的影响。研究结果表明,在室温下,pH 7.3-7.7 Na2HPO4-KH2PO4缓冲溶液中,体系中加入十二烷基苯磺酸钠、十二烷基磺酸钠后荧光强度增强,加入十二烷基硫酸钠后荧光强度减弱。建立了荧光光度法测定十二烷基苯磺酸钠的新方法。     

Double-strand hydrolysis of plasmid DNA by dicerium complexes at 37 degrees C.

Significant effort has been made to develop synthetic metal complexes that hydrolyze DNA. Here we report a new dicerium complex, Ce(2)(HXTA) (HXTA = 5-methyl-2-hydroxy-1,3-xylene-alpha,alpha-diamine-N,N,N',N'-tetraacetic acid), which can hydrolyze DNA at pH 8 and 37 degrees C. This complex hydrolyzes DNA restriction fragments to give products with high regioselectivity, affording >90% 5'-OPO(3) and 3'-OH ends, like the products of DNA hydrolyzing enzymes. Ce(2)(HXTA) also hydrolyzes Litmus 29 plasmid DNA to afford both nicked and linear DNA. Analysis of the relative amounts of supercoiled, nicked, and linear DNA present show that there is one double-strand cleavage per ten single-strand cleavages, indicating that the linear DNA formed cannot be the result of two random single-strand cleavage events. The kinetics of nicked and linear DNA formation are comparable, both being associated with apparent first-order rate constants of approximately 1 x 10(-)(4) s(-)(1) for complex concentrations of 10(-)(5)-10(-)(4) M. These observations suggest that similar factors affect the hydrolysis of the first and second DNA strands and that cleaving the phosphodiester bond is likely the rate determining step in both cases. This is the first detailed study of a metal complex shown to mimic DNA hydrolases in their capability to effect double-strand DNA hydrolysis regioselectively at the 3'-O-P bond.     

O2 chemistry of dicopper complexes with alkyltriamine ligands. Comparing synergistic effects on O2 binding

Two dicopper(I) complexes containing tertiary N-methylated hexaaza ligands which impose different steric constraints to the Cu ions have been synthesized, and their reactivity toward O2 has been compared with a mononuclear related system, highlighting the importance of cooperative effects between the metal centers in O2 activation.     

2-乙基己基膦酸单2-乙基己酯铜(Ⅱ)萃合物的ESR谱和电子结构

有机酸性膦(磷)酸酯与二价铜离子的萃合物研究已有报导。文献[1]对该萃合物的结构做了初步讨论,认为由于在正庚烷溶剂中铜萃合物的吸收光谱呈一宽的吸收带,最大吸收峰位置在13600cm~(-1)处,难以推断该萃合物是四面体还是平面正方形结构。本文在291和77K下测定了萃合物的ESR谱,并用量子化学的CNDO/2方法对该萃合物的电子结构作了进一步研究。     

一种带袖珍计算机的流动注射分析实验装置

为了利用实验室现有仪器设备进行流动注射分析实验,本文作者组装了一套带袖珍计算机的流动注射分析实验装置,该装置由一台72-1型分光光度计、一只流通此色池,一架SHARP PC-1500袖珍计算机、一台多通道蠕动泵和一只旋转式进样阀组合而成。该装置具有组装和折卸容易,数据可自动采集和处理及设备费用低廉等特点,作者用此装置对cd~(++)标准溶液进行了测试,得到了较满意的结果。