PicoGreen dsDNA Assay Kit is a highly sensitive and specific fluorescence-based assay designed for the quantification of double-stranded DNA (dsDNA). It is widely used in molecular biology to measure dsDNA concentration in various biological samples with high accuracy, even in the presence of single-stranded DNA (ssDNA), RNA, and free nucleotides.
Principle
The assay uses the PicoGreen reagent, a fluorescent nucleic acid stain that selectively binds to dsDNA. Upon binding, PicoGreen exhibits a strong increase in fluorescence intensity with excitation and emission maxima approximately at 502 nm and 523 nm, respectively. This fluorescence enhancement allows detection of dsDNA at very low concentrations, down to a few picograms per milliliter.
Assay Workflow
The PicoGreen assay is simple and rapid. The dye working solution is prepared by diluting the concentrated PicoGreen reagent. This working solution is then added directly to the sample containing dsDNA. After an incubation period of about 5 minutes at room temperature and protected from light, the fluorescence intensity is measured using a fluorescence microplate reader or fluorometer. The sample fluorescence is compared against a DNA standard curve to determine dsDNA concentration accurately over a broad dynamic range spanning three orders of magnitude.
Performance and Specificity
PicoGreen selectively detects dsDNA and has minimal interference from ssDNA, RNA, proteins, or free nucleotides in the samples. Its sensitivity significantly surpasses traditional UV absorbance-based DNA quantification, saving precious samples due to the low volume required. Moreover, the assay is compatible with 96- and 384-well plate formats, facilitating high-throughput applications.
The PicoGreen dsDNA Assay Kit provides a rapid, sensitive, and specific method for dsDNA quantification. Its fluorescence-based detection offers superior accuracy compared to absorbance methods, with excellent tolerance to common contaminants. Its ease of use and compatibility with microplate formats make it well suited for research and clinical laboratories requiring reliable dsDNA measurements.