As higher throughput methods for DNA determination are being developed, more automated procedures are needed for rapid assessment of extracted DNA quantity prior to DNA amplification. To this end, the Forensic Science Service has developed a PicoGreen assay that is capable of detecting as little as 0.25ng/mL of double-stranded DNA in a 96-well microtiter plate format (Hopwood et al. 1997). PicoGreen is a fluorescent interchelating dye whose fluorescence is greatly enhanced when bound to double-stranded DNA.
To perform this microtiter plate assay, 5 | L of sample are added to 195 | L of a solution containing the PicoGreen dye. Each sample is placed into an individual well on a 96-well plate and then examined with a fluorometer. A 96-well plate containing 80 individual samples and 16 calibration samples can be analyzed in under 30 minutes (Hopwood et al. 1997). The DNA samples are quantified through comparison to a standard curve. This assay has been demonstrated to be useful for the adjustment of input DNA into the amplification reaction of STR multiplexes (Hopwood et al. 1997). It has been automated on a robotic workstation as well. Unfortunately, this assay quantifies total DNA in a sample and is not specific for human DNA.
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This book discusses the futility of curing stammering by common means. It traces various attempts at curing stammering in the past and how wasteful these attempt were, until he discovered a simple program to cure it. The book presents the life of Benjamin Nathaniel Bogue and his struggles with the handicap. Bogue devotes a great deal of text to explain the handicap of stammering, its effects on the body and psychology of the sufferer, and its cure.