Highly sensitive DNA detection with a combination of 2 DNA-intercalating dyes for microchip electrophoresis

A highly sensitive DNA detection method using a combination of ethidium bromide (EtBr) and SYBR Green II (SG II) for microchip electrophoresis was developed. By use of the combination of these intercalating DNA-staining dyes for microchip electrophoresis with Hitachi SV1100 system, the fluorescence intensities corresponding to DNA fragments were obviously increased over those obtained with EtBr only, with accuracy of DNA sizing and quantification. The detection limit with EtBr and the combination of EtBr and SG II were 0.048 and 0.007 ng/μl, respectively. This highly sensitive DNA detection just using the combination of these dyes offering high resolution in a short time will be useful for various biological analyses.