YOYO-1 Iodide (491/509)

YOYO-1 Iodide (491/509) is a cyanine nucleic acid stain that exhibits strong fluorescence upon binding to double-stranded DNA, making it a widely used reagent for DNA visualization and quantitative nucleic acid workflows. The dye's excitation/emission profile around 491/509 nm supports common blue-laser and green-channel fluorescence setups, and its cationic, DNA-intercalating character enables direct labeling without complex probe conjugation. YOYO-1 Iodide (491/509) is frequently selected for electrophoresis staining, gel-based sizing, and fluorescence readouts where dsDNA content is the primary variable.

1. Gel Electrophoresis DNA Staining

YOYO-1 Iodide (491/509) is routinely used to stain agarose or polyacrylamide gels for post-run visualization of DNA bands, allowing researchers to assess fragment size and relative dsDNA abundance using standard fluorescence gel imaging systems. Molecular biology labs and genomics groups often choose this dye because the fluorescence signal develops upon dsDNA intercalation, producing clear band contrast in the instrument channels aligned with the dye's 491/509 nm spectral window. The reagent is also commonly used when workflows require straightforward, direct staining of nucleic acid samples prior to imaging, supporting routine cloning, PCR product screening, and DNA purification QC.

2. Fluorescence Microscopy DNA Visualization

YOYO-1 Iodide (491/509) supports fluorescence microscopy experiments where dsDNA distribution is visualized in fixed specimens or prepared nucleic acid materials, including stained cell preparations and DNA-containing samples used in molecular imaging studies. Because the dye binds to double-stranded DNA and yields bright fluorescence under appropriate excitation, it is frequently incorporated into microscopy protocols to map nuclear and chromatin-associated DNA signals or to label DNA in experimental constructs. Imaging teams often select YOYO-1 Iodide (491/509) when they need a dsDNA-selective fluorescent label compatible with common fluorescence microscope filter sets and documentation workflows focused on nucleic acid localization.

3. Flow Cytometry DNA Content Analysis

YOYO-1 Iodide (491/509) is used in flow cytometry for measuring cellular DNA content and for nucleic acid-based population analysis in prepared samples where dsDNA staining is the readout. Researchers typically employ the dye in staining workflows that intercalate into double-stranded DNA, enabling fluorescence intensity to correlate with DNA amount across cell-cycle-related distributions. Flow cytometry users value the dye's compatibility with instrument channels tuned near the 491/509 nm region, which helps integrate YOYO-1 Iodide (491/509) into multi-parameter panels that include DNA content as one of the measured fluorescence signals.

4. Nucleic Acid Quantification Assays

YOYO-1 Iodide (491/509) is frequently applied as a fluorescent dsDNA reporter in plate-based or cuvette-based quantification workflows, including standard curve generation for DNA concentration and monitoring of dsDNA yield during molecular biology processes. In these assays, the fluorescence response is driven by intercalation into double-stranded DNA, enabling direct readout of nucleic acid levels using fluorescence readers configured for the dye's excitation/emission range. Bioprocessing and research labs often use YOYO-1 Iodide (491/509) when they need a practical fluorescence-based method to compare dsDNA amounts across samples such as PCR products, plasmid preparations, or DNA extracted from experimental materials.