Wang Shijun, Milam Jenifer, Ohlin André C, Rambaran Varma H, Clark Eva, Ward Woodrow, Seymour Luke, Casey William H, Holder Alvin A, Miao Wujian
Department of Chemistry and Biochemistry, The University of Southern Mississippi, Hattiesburg, Mississippi 39406, USA.
Anal Chem. 2009 May 15;81(10):4068-75. doi: 10.1021/ac900282y.
The electrochemical behavior of a trinuclear ruthenium(II)-containing complex, ((phen)(2)Ru(dpp))(2)RhCl(2) (where phen = 1,10-phenanthroline, dpp = 2,3-bis(2-pyridyl)pyrazine), was studied in acetonitrile (MeCN) and aqueous solutions. In MeCN containing 0.10 M tetra-n-butylammonium perchlorate (TBAP), the complex displayed a reversible, overlapping Ru(II/III) redox process with E(1/2) = +1.21 V vs Ag/Ag(+) (10 mM), an irreversible reduction of Rh(III/I) at -0.73 V vs Ag/Ag(+), and two quasi-reversible dpp/dpp(-) couples with E(1/2) = -1.11 and -1.36 V vs Ag/Ag(+) at a Pt electrode with a scan rate of 50 mV s(-1). In 0.20 M Tris buffer solution (pH 7.4), an irreversible, overlapping Ru(II/III) oxidation at +1.48 V vs Ag/AgCl (3 M KCl), and an irreversible reduction of Rh(III/II) at -0.78 V vs Ag/AgCl were observed at a glassy carbon electrode with a scan rate of 50 mV/s. Investigations on the electrogenerated chemiluminescence (ECL) of the complex revealed that 2-(dibutylamino) ethanol (DBAE) was superior to tri-n-propylamine (TPrA) as an ECL coreactant within their entire concentration range of 10-100 mM in MeCN, and in aqueous media, as low as 1.0 nM of the complex can be detected using TPrA coreactant ECL. A maximum ECL emission of 640 nm, which is about 55 nm blue shift to its fluorescence, was observed in MeCN with DBAE as a coreactant. Interactions of the complex with calf thymus DNA (ctDNA) were conducted with a flow-cell based quartz-crystal microbalance, and a binding constant of 2.5 x 10(5) M(-1) was calculated on the basis of the Langmuir isotherm equation.
研究了一种含三核钌（II）的配合物((phen)(2)Ru(dpp))(2)RhCl(2)（其中phen = 1,10-菲咯啉，dpp = 2,3-双（2-吡啶基）吡嗪）在乙腈（MeCN）和水溶液中的电化学行为。在含有0.10 M四丁基高氯酸铵（TBAP）的MeCN中，该配合物显示出一个可逆的、重叠的Ru（II/III）氧化还原过程，相对于Ag/Ag(+)（10 mM），E(1/2) = +1.21 V，在相对于Ag/Ag(+)为 -0.73 V处有Rh（III/I）的不可逆还原，以及在扫描速率为50 mV s(-1)的Pt电极上有两个准可逆的dpp/dpp(-) 氧化还原对，相对于Ag/Ag(+)，E(1/2) = -1.11和 -1.36 V。在0.20 M Tris缓冲溶液（pH 7.4）中，在扫描速率为50 mV/s的玻碳电极上观察到相对于Ag/AgCl（3 M KCl）在 +1.48 V处有一个不可逆的、重叠的Ru（II/III）氧化，以及在 -0.78 V处有Rh（III/II）的不可逆还原。对该配合物的电化学发光（ECL）研究表明，在MeCN中10 - 100 mM的整个浓度范围内，2-（二丁基氨基）乙醇（DBAE）作为ECL共反应剂优于三正丙胺（TPrA），并且在水性介质中，使用TPrA共反应剂ECL可检测低至1.0 nM的该配合物。以DBAE作为共反应剂在MeCN中观察到最大ECL发射波长为640 nm，相对于其荧光发生了约55 nm的蓝移。使用基于流通池的石英晶体微天平研究了该配合物与小牛胸腺DNA（ctDNA）的相互作用，并根据朗缪尔等温方程计算出结合常数为2.5×10(5) M(-1)。
