On This Page | Prestained Protein Ladders | Unstained Protein Ladders | Western Blotting Protein Standards | IEF and 2D Electrophoresis Protein Standards | Resources |
Pick the Best Standards for Your Blots!
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
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 | Kaleidoscope Standards | Dual Xtra 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.
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* | Broad-Range SDS-PAGE Standards | Low-Range SDS-PAGE Standards | Natural High-Range 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.
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| 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 | 2-D SDS-PAGE 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
Introducing the Western Blot Learning Center
Perfect your western blotting. Learn from the experts.
Get Tips
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Protein Standards Selection Guide
(PDF 291 KB)For quick guidance on choosing the best standard for your application.
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Little Book of Standards
(PDF 5.12 MB)Complete reference information for all of Bio-Rad’s protein standards and nucleic acid standards.
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Protein Gel Migration Charts
View banding patterns for Bio-Rad protein standards on Bio-Rad and competitor gels.
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Free Protein Standards Selection Magnet
Place this handy selection guide magnet on your refrigerator or lab bench to eliminate the guesswork and make protein standard selection simple.
Request a Magnet
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Electrophoresis Guide
(PDF 8.35 MB)Theory and techniques, Bio-Rad products, tips and troubleshooting.
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Protein Blotting Guide
(PDF 7.11 MB)Details on blotting technology, available products, and tips and techniques.
