Nucleic Acids Research, 1985, Vol. 13, No. 22 8083-8091
© 1985
Articles |
Detection of subpicogram quantities of specific DNA sequences on blot hybridization with biotinytated probes
University of Oxford, Nuffield Department of Pathology, John Radcliffe Hospital Oxford 0X3 9DU, UK
Received July 30, 1985. Revised October 28, 1985. Accepted October 28, 1985.
A sensitive method for detecting biotinylated DNA probes on dot and Southern blots is describedwhich is based on the principle outlined by Leary et al (1). This system has two main components: detection of biotinylated DNA by a two-step procedure with streptavidin and poly(alkaline phosphatase); and blocking background with Tween 20. 32fg and 80fg of
phage DNA was detected on dot and Southern blot hybridizations respectively. 150fg of ß-globin was detected on Southern blots of genomic DNA. This method is fast, reproducible and can detect single copy genes in 0.25µg of human genomic DNA on Southern blots.