What is CY5?

CY5 Dye:

    • Type: Near-infrared (NIR) fluorescent dye molecule commonly used in bioconjugation for applications like microscopy, flow cytometry, and in vivo imaging.
    • Excitation/Emission wavelength:
        • Excitation peak: Around 675 nm (red light)
        • Emission peak: Around 694 nm (near-infrared light)

Key advantages of CY5:

    • High brightness: Offers strong fluorescence intensity for sensitive detection.
    • Good photostability: Resists fading under light exposure.
    • Convenient conjugate labeling: Can be readily attached to biomolecules like proteins and antibodies.
    • Near-infrared emission: Minimizes background autofluorescence from biological samples,improving signal-to-noise ratio.

Key disadvantages of CY5:

    • Requires specialized equipment: Needs NIR-compatible excitation and detection instruments.
    • Cost: More expensive compared to some visible wavelength dyes.

CY5 Filters:

    • Purpose: Designed to selectively transmit light within the excitation and emission ranges of CY5,blocking other wavelengths for improved signal-to-noise ratio.

Specific Filter Profiles:

Excitation Filter:

    • Bandwidth: Choose between narrower bandwidth for higher selectivity (potentially lower signal) or wider bandwidth for higher signal (potentially lower selectivity). Consider your application's needs.
    • Examples:
        • Narrow: Omega Filters XF660-20 (640-680 nm), Chroma Technology ET675/25M (650-685 nm)
        • Wider: Omega Filters XF650-40 (630-690 nm), Chroma Technology ET660/40M (640-700 nm)

Emission Filter:

    • Bandwidth: Same considerations as excitation filter.
    • Examples:
        • Narrow: Omega Filters XF710-20 (690-730 nm), Chroma Technology ET700/75M (685-710 nm)
        • Wider: Omega Filters XF705-50 (680-730 nm), Chroma Technology ET725/50M (700-750 nm)

Dichroic Filter:

    • Combines excitation and emission filtering in one component. Useful for multi-color imaging with different dyes.
    • Examples:
        • Omega Filters Dual-Band Dichroic Filter (Excitation: 628/650 nm, Emission: 685/710 nm)
        • Semrock Cy5/Cy7 Dichroic Beamsplitter (Excitation: 635/650 nm, Emission: 670/720 nm)

Remember:

    • Adapt these examples based on your specific application and equipment for optimal results.
    • Consider factors like instrument compatibility, desired selectivity, and budget when choosing filters.
    • Consult filter manufacturers for detailed specifications and application support.
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