Protein Ladders and Standards (Markers)

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Pick the Best Standards for Your Blots!

Interactive Selection Guide for Protein Standards

Just click on the light source in our interactive guide and see how banding pattern changes with light source. This interactive guide helps you pick the best protein standard for your gels and blots. 

Try Our Interactive Selection Guide

Precision Plus Protein Dual Color Standards

Featured ProductPrecision Plus Protein Dual Color Standards

  • Brighter for easier target protein identification
  • Stronger band intensity after blot processing
  • Sharper for more accurate MW estimation

Prestained Protein Ladders

Precision Plus Protein Standards have the same gel migration patterns, with three high-intensity reference bands (25, 50, and 75 kD), and provide exceptional lot-to-lot molecular weight consistency.

  Dual Color Standards
Dual Color Standards
Kaleidoscope Standards
Kaleidoscope Standards
Dual Xtra Standards
Dual Xtra Standards
All Blue Standards
All Blue Standards
Bands 10 10 12 10
Colors 2 5 2 1
MW range 10–250 kD 10–250 kD 2–250 kD 10–250 kD
Band sharpness High High High High
Packaging options Sample (5 applications) 1610374S
50 applications 1610374 1610375 1610377 1610373
250 applications 1610394 1610395 1610397 1610393

Prestained Natural Protein Standards

Prestained natural protein standards for SDS-PAGE and western blotting provide a quick and easy way to monitor protein separation during electrophoresis and to assess transfer efficiency on blots. Each lot of prestained protein standards is individually calibrated for estimating the MW of sample proteins.

Information

Important information

Prestained Natural Protein Standards will soon be phased out. We recommend the Precision Plus Protein Prestained Recombinant Protein Standards above as replacements.

Unstained Protein Ladders

Unstained natural protein standards allow accurate MW determination with uniform band intensities on SDS-PAGE gels stained with Coomassie Blue or zinc. Precision Plus Protein Unstained Recombinant Protein Standards are Strep-tagged, enabling immunodetection and molecular weight determination on western blots.

  Precision Plus Protein Unstained Standards
Precision Plus
Protein Unstained
Standards*
Broad-Range SDS-PAGE Standards
Broad-Range
SDS-PAGE
Standards
Low-Range SDS-PAGE Standards
Low-Range
SDS-PAGE
Standards
Natural High-Range SDS-PAGE Standards
Natural High-Range
SDS-PAGE
Standards
Natural Polypeptide SDS-PAGE Standards
Natural Polypeptide
SDS-PAGE
Standards
Bands 10 9 6 5 6
MW range
(Note: Actual weights may vary; lot-specific MWs are included with each vial.)
10–250 kD 6.5–210 kD 14–97 kD 45–200 kD 1.4–26.6 kD
Band sharpness High Low Low Low Low
Packaging options 100 applications 1610363 1610317 1610304 1610303 1610326
500 applications 1610396

* Recommended for use with Bio-Rad's TGX Stain-Free Precast Gels and TGX Stain-Free FastCast Acrylamide handcast gels.

Western Blotting Protein Standards

Western blotting protein standards can be used for both fluorescent visualization and colormetric or chemiluminescent immunodetection on western blots. Precision Plus Protein WesternC Standards are combination protein standards containing ten prestained, Strep-tagged recombinant proteins, enabling both fluorescent visualization on gels and colorimetric or chemiluminescent western blot detection with StrepTactin-AP or StrepTactin-HRP Conjugate.

Western Blotting Protein Standards
Bands 10
Colors 2
MW range 10–250 kD
Band sharpness High
Packaging options 50 applications Standards only (1610376)
Standards and StrepTactin-HRP Conjugate (1610385)
250 applications Standards only (1610399)
Standards and StrepTactin-HRP Conjugate (1610398)
 

IEF and 2D Electrophoresis Protein Standards

IEF and 2D protein standards are a mixture of native proteins with isoelectric points (pI) ranging from 4.45 to 9.6, providing reproducible pI calibration in native PAGE or agarose IEF gels. 2-D SDS-PAGE protein standards provide calibrated references for protein pI and molecular weight in the second dimension.

  Precision Plus Protein Prestained Plug Standards
Precision Plus Protein
Prestained Plug Standards
2-D SDS-PAGE Standards
2-D SDS-PAGE
Standards
Isoelectric Focusing (IEF) Standards
Isoelectric Focusing
(IEF) Standards
Bands 10 7 9
Colors 1 1
MW range/pI range 10–250 kD 17.5–76 kD, pI 4.5–8.5 pI 4.45–9.6
Packaging
options
24 applications 1610378
Number of applications depends
on staining method
1610320 1610310

* 2-D standards: use 2.5 µl per mini gel for Coomassie staining (200 applications) or 0.5–2.5 µl for silver staining (up to 1,000 applications); use 1.0–5.0 µl for full-length gels (16–20 cm) to yield 100 or up to 500 applications, respectively.
IEF standards: use 5 µl per mini gel for Coomassie staining or 0.5 µl for silver staining to yield 50 or 500 applications, respectively.

Resources

 
  • Electrophoresis Guide

    Electrophoresis Guide
    (PDF 8.35 MB)

    Theory and techniques, Bio-Rad products, tips and troubleshooting.

  • Protein Blotting Guide

    Protein Blotting Guide
    (PDF 7.11 MB)

    Details on blotting technology, available products, and tips and techniques.