Ru(phen)2(dppz)]2+ Assemble on the Surface of the SDS Micelle and Its Application for the Determination of DNA

Abstract

The solution of [Ru(phen) 2 (dppz)] 2+ and SDS has high Resonance Light Scattering (RLS) signals due to [Ru(phen) 2 (dppz)] 2+ assemble on the surface of the SDS micelle. Because of the high affinity (K B > 10 6 L mol -1 ) between [Ru(phen) 2 (dppz)] 2+ and DNA, the adding of DNA in the solution of [Ru(phen)2(dppz)]2+-SDS makes the dissociation of [Ru(phen) 2 (dppz)] 2+ -SDS, and results in decreasing of the RLS signals and increasing of the absorbance. Based on this, a novel method is proposed for DNA assay. Under optimum condition, good linear relationship was obtained within the concentration range of 0.018-1.26 μg mL -1 , the linear equation is J RLS = 504.8-348.8 c (c: μg mL -1 ) and the correlation coefficient (r) is 0.9992. The detect limit for calf thymus DNA is 8.6 ng mL -1 . The proposed method was successful applied to determine the extracted colibacillus plasmid DNA.