Protein Electrophoresis

SYPRO Protein Detection Reagents


Sigma offers a collection of Molecular Probes’ SYPRO stains for luminescent detection of proteins separated by PAGE. Different stains are available for 1D gel, 2D gel, and membrane detection of protein. The collection of SYPRO stains includes SYPRO Ruby, SYPRO Tangerine, SYPRO Orange, and SYPRO Red stains.


SYPRO Ruby Gel Stain

Molecular Probes' SYPRO Ruby gel stain is a ready–to–use, ultra sensitive, luminescent stain for the detection of proteins separated by PAGE. Designed especicially for 2D PAGE, SYPRO Ruby also performs impressively in PAGE and IEF gels. Ex/Em = 280, 450/610 nm

Features & Benefits

  • Uses a simple staining protocol with no possibility of over–staining
  • Delivers a linear quantitation range over three orders of magnitude
  • Stains glycoproteins, lipoproteins, calcium binding proteins, fibrillar proteins and others
  • Will not stain extraneous nucleic acids
  • Sensitive to 1 ng of protein


SYPRO Ruby protein gel stain compared to a silver stain.
Proteins from a fibroblast cell lysate were run on identical 2–D gels and stained with SYPRO Ruby protein gel stain (left) or silver stain (right). The grayscale values of the gel stained with SYPRO Ruby dye have been inverted for easier comparison with the silver–stained gel.

Product #  Product Name Size
S4942 SYPRO Ruby Gel Stain 1 kit

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SYPRO Tangerine Gel Stain

Molecular Probes' SYPRO Tangerine gel stain is an extremely versatile stain for proteins in SDS gels. Proteins stained without fixation can be used for zymography (in–gel enzyme activity) assays. Stained proteins can also be eluted from gels and used for further analysis. The stain does not alter protein structure and does not interfere with mass spectrometry. In addition, staining does not iterfere with the transfer of proteins to membranes, allowing visualization before preceeding with Western blotting. Ex/Em = 300, 490/640 nm

Features & Benefits

  • Detects 4–8 ng of protein per mini–gel band
  • Staining is complete in less than an hour
  • Selectively detects proteins without staining nucleic acids or lipopolysacharide contaminants


Sypro Tangerine Gel stain Zymographic detection of β–D–glucuronidase activity after visualization of total protein patterns using SYPRO Tangerine protein gel stain.
Molecular weight standards containing decreasing amounts of Escherichia coli β–glucuronidase were run on identical SDS–polyacrylamide gels and stained with SYPRO Tangerine protein gel stain (top) followed by incubation with ELF 97 D–glucuronidase substrate to detect the activity of β–D–glucuronidase (bottom).

Product #  Product Name Size
S5942 SYPRO Tangerine Gel Stain 1 kit

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SYPRO Orange Gel Stain

Molecular Probes' SYPRO Orange protein gel stain provides fast, simple, sensitive staining of proteins in electrophoretic gels.

Features & Benefits

  • Detect 4–8 ng of protein per mini–gel band
  • Minimize protein–to–protein variability through increased staining consistency and eliminate negative staining
  • Fluorescence intensity is linear with protein quantity over three orders of magnitude, much broader than Coomassie or Silver Staining can provide


Protein Molecular Weight Standards separated on identical 12% SDS–PAGE gels and then stained with either SYPRO Orange (left) or SYPRO Red (right) protein gel stains.

Product #  Product Name Size
S5692 SYPRO Orange Gel Stain 1 kit

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SYPRO Red Gel Stain

Molecular Probes' SYPRO Red protein gel stain provides fast, simple, sensitive staining of proteins in electrophoretic gels.

Features & Benefits

  • Detect 4–8 ng of protein per mini–gel band
  • Minimize protein–to–protein variability through increased staining consistency and eliminate negative staining
  • Fluorescence intensity is linear with protein quantity over three orders of magnitude, much broader than Coomassie or Silver Staining can provide

    See above gel


    Product #  Product Name Size
    S5817 SYPRO Red Gel Stain 1 kit

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    SYPRO Protein Gel Starter Kit

    The SYPRO gel starter kit includes three fluorescent protein stains (SYPRO Orange, SYPRO Red, and SYPRO Tangerine) as well as a SYPRO photographic filter. Proteins as small as 6.5 kDa can be detected with no observed staining of liposaccharides or nucleic acids.


    Product #  Product Name Size
    SY0100 SYPRO Protein Gel Starter Kit 1 kit

    SYPRO is a registered trademark of Molecular Probes.

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