Quantitation of DNA hybridization in a silicon sensor-based system: application to PCR

Environmental Dissemination of FoodborneSalmonellain Preharvest Poultry Production: Reservoirs, Critical Factors, and Research Strategies

“…123,134−139 The hybridized DNA is then bound by its biotin label to a biotinylated membrane stick and the fluorescein label is allowed to bind to a polyclonal anti-fluorescein antibody conjugated to urease. 136 The presence or absence of the amplicon specific for the hns sequence is based on the incremental changes in pH (measured in microvolts per second) resulting when the urease-containing sandwich is exposed to urea in a pH-sensitive potentiometric sensor.…”

Electrochecmical biosensors for DNA sequence detection

“…Two DNA biosensors using potentiometric transduction have been reported by this group: one is designed to quantitate total DNA [25], while the second is designed for sequence-selective detection of PCR products [24]. Both rely on the capture of biotinylated species onto streptavidin-coated membranes, and the detection of a local pH change produced at the membranecovered sensor surface by an enzyme label (urease).…”

“…More recently, the same group has reported a scheme for the sequence-selective detection of PCR products with the lightaddressable potentiometric sensor [24], using two DNA probes, one labelled with biotin and the other with fluorescein, instead of the DNA-binding proteins used in the total DNA sensor. In this work, analyte DNA (PCR product) is denatured and incubated with the two DNA probes.…”

Identification of capsule-forming Bacillus anthracis spores with the PCR and a novel dual-probe hybridization format

“…Detection of PCR-amplified products. The amplified products were detected by ethidium bromide staining of DNA separated by polyacrylamide gel electrophoresis (PAGE), as well as a novel dual-probe hybridization format in which we used a biosensor capable of detecting minute changes in pH (Molecular Devices, Menlo Park, Calif.) (13). Electrophoresis was performed by using 15 to 20 ,ul of PCR product on a 4 to 12% polyacrylamide gel (NOVEX, San Diego, Calif.) and a constant voltage of 100 V for 1 to 2 h. The gels were stained with ethidium bromide (1 ,ug/,ul) for 5 to 10 min and were photographed by using a UV transilluminator and type 665 film (Polaroid Corp., Cambridge, Mass.…”

“…In the dual-probe hybridization format we relied on simultaneous hybridization of both a biotin-labeled probe and a fluorescein-labeled probe to target regions within the PCR-amplified product (13). The 5' biotin-labeled probe,…”