SYBR Green II | CAS 195199-08-7

SYBR Green II is a high-affinity, nucleic-acid-binding fluorescent dye widely used to report double-stranded DNA in fluorescence-based nucleic acid workflows. As a cyanine-like intercalating dye, it produces strong fluorescence enhancement upon binding to dsDNA, enabling convenient monitoring of DNA amplification and post-amplification DNA content. Its performance in real-time fluorescence and endpoint DNA staining formats makes it a common reagent for molecular biology, genomics research, and assay development.

1. Real-Time PCR DNA Monitoring

SYBR Green II is used as a dsDNA reporting dye in real-time PCR workflows, where fluorescence increases in proportion to DNA accumulation during thermal cycling. Researchers and assay developers rely on it for amplification tracking in qPCR experiments that do not require probe-based sequence specificity, including gene expression studies, microbial load quantification, and screening of primer performance. Because SYBR Green II responds to double-stranded DNA, it is also commonly adopted for method optimization and comparative studies where the primary readout is total dsDNA generated by PCR.

2. Gel Electrophoresis DNA Staining

SYBR Green II is frequently employed for endpoint visualization of PCR products and DNA fragments on agarose gels, offering a straightforward alternative to traditional DNA stains for many routine workflows. Molecular biology labs use it to confirm amplicon size, assess amplification success, and compare relative DNA amounts across samples. The dye's strong fluorescence upon dsDNA binding supports sensitive band visualization under standard blue-light or UV imaging systems, making it practical for daily gel-based analysis in research and industrial molecular biology environments.

3. Nucleic Acid Quantification Assays

SYBR Green II is applied in fluorescence-based nucleic acid quantification assays where dsDNA concentration or DNA content needs to be measured in solution. Typical users include genomics and molecular diagnostics research groups, bioprocessing and QC teams, and platform developers who need a convenient readout for DNA yield, normalization, or sample-to-sample comparison. In these formats, the dye's dsDNA-dependent fluorescence enables rapid measurement using plate readers or fluorimeters, supporting workflows such as DNA quantification after extraction, library preparation steps, or nucleic acid normalization prior to downstream analyses.

4. DNA Binding and Amplification Studies

SYBR Green II is also used in fluorescence experiments that monitor DNA formation or DNA binding behavior in the context of nucleic acid chemistry and amplification optimization. Researchers use it to evaluate how experimental conditions affect dsDNA generation, to compare primer sets by tracking amplification kinetics, and to support troubleshooting when amplification efficiency or product composition changes. This application leverages the dye's ability to report dsDNA accumulation as a direct fluorescence readout in controlled laboratory studies where DNA is the primary signal-generating species.