A bacteriophage M13 based sandwich hybridization assay for the detection of hepatitis B virus in human blood

A two step hybridization procedure was developed to detect the presence of hepatitis B virus in blood samples using bacteriophage M13 radiolabelled DNA as probe. During the first step of hybridization, single-stranded bacteriophage M13 tg 130 DNA, with 3.2 kb HBV DNA cloned into it, was hybridized to target HBV DNA immobilized on nitrocellulose membrane filter. In the second step of hybridization, M13 DNA annealed to HBV target is detected with the help of double stranded form of M13 DNA. The assay offers minimum 4- to 6-fold higher sensitivity in comparison to single-step conventional hybridization assays. Additionally M13 DNA offers itself as universal probe.