Use of the fluorescent intercalating dyes POPO-3, YOYO-3 and YOYO-1 for ultrasensitive detection of double-stranded DNA separated by capillary electrophoresis with hydroxypropylmethyl cellulose and non-cross-linked polyacrylamide

Abstract

Double-stranded DNA is separated by means of capillary electrophoresis with either hydroxypropylmethyl cellulose or non-cross-linked polyacrylamide as the separation medium. A high-sensitivity laser-induced fluorescence detector is used to monitor the elution of DNA that has been stained with the intercalating dyes POPO-3, YOYO-3 or YOYO-1. Detection limits are on the order of 1 zmol of dye. The dye is incorporated at a rate of 1 dye molecule for every 10 base pairs in the double-stranded DNA; as a result, detection limits are a few yoctomoles of fluorescently labeled DNA.