Western Blotting without Trial and Error: Use PrecisionAb Antibodies

Watch how PrecisionAb Validated Western Blotting Antibodies are defining a new standard of quality that you can trust to deliver superior results and reproducibility in western blotting.

Create Flawless Western Blots with PrecisionAb Antibodies

The western blotting experts at Bio-Rad have joined forces with the antibody experts at Bio-Rad to develop PrecisionAb Antibodies. These premium antibodies for western blotting provide superior performance and reproducibility to help you produce the highest-quality western blotting data.


PrecisionAb Antibodies are individually validated for western blotting by researchers in the laboratory to give you the best performance in western blotting detection. Every PrecisionAb Antibody is rigorously tested and selected based on the parameters most important for western blotting detection:

  • High specificity - validated against whole cell lysates and selected based on stringent performance metrics
  • High sensitivity - capable of detecting the target without enrichment
  • Consistency - every lot of antibody meets the same strict quality control criteria


PrecisionAb Antibody targets include a growing list of common proteins from key cellular pathways.

PrecisionAb Antibody Validation Data

Selection Criteria

PrecisionAb Antibody validation results. Western blot analysis of 12 whole-cell lysates probed with PrecisionAb Mouse Anti-Human PCNA Primary Antibody followed by detection with goat anti-mouse secondary antibody and visualized on the ChemiDoc™ MP Imaging System with Clarity™ Western ECL Substrate.

PrecisionAb Antibodies are assessed in the laboratory using the most stringent validation criteria in the industry to ensure industry-leading performance and reproducibility for western blotting.

Each PrecisionAb Antibody is tested against whole-cell lysates (up to 12 cell lines) expressing proteins at endogenous levels. Western blots are run by a group of scientists who scrutinize the data based on comparison against relevant bioinformatic database references, signal-to-background ratio, and other parameters.

Only those antibodies meeting the standards for all criteria are released as PrecisionAb Antibodies.

The results are high-performing antibodies that exhibit the highest levels of specificity and sensitivity, yielding superior performance in western blotting applications. 

User Testing Protocol

PrecisionAb Antibodies were evaluated by working proteomics researchers in side-by-side competitive testing. Each test site was asked to evaluate five PrecisionAb Antibodies using targets selected from ~35 antibodies based on research interests. Each PrecisionAb Antibody was used in western blotting alongside antibodies from two other vendors, each used according to the manufacturer’s recommendations.

The researchers were asked to select the competing antibodies as they normally would, by looking at publications and/or information on vendor websites. Researchers used their vendor-recommended protocols with samples provided in the form of whole-cell lysates, all using Bio-Rad’s Criterion™ TGX™ Gels, the Trans-Blot® Turbo™ Transfer System, and nitrocellulose membrane stacks.

Selected User Testing Results

Prof. Aldrin V. Gomes

Results Summary: Prof. Aldrin V. Gomes
University of California, Davis

Prof. Gomes studies molecular mechanisms of signal transduction in muscle contraction and cardiovascular disease, relying heavily on biophysical proteomic techniques. As an editor of several journals, he has observed that low-quality western blot data is routinely submitted, leading many to question the accuracy of protein quantification by western blotting. He has deeply examined key success factors in western blotting, including antibody selection (Ghosh et al. 2014, Gilda and Gomes 2013, Gomes 2009, Gomes 2014).

The Gomes Lab conducted side-by-side testing of PrecisionAb Antibodies with antibodies for the same targets from two leading antibody suppliers. Prof. Gomes summarized the results as follows:

“Antibodies provided from Bio-Rad were of very high quality for 80% of the antibodies tested, suggesting most antibodies will be great for western blotting. The other antibody tested was of high quality, on par with the best antibodies available for the target protein.”

Side-by-side testing of anti-human Bcl-2 antibodies with Jurkat cell lysate.

Left, the western blot and the stain-free total protein imaging data for each antibody.

Right, the relative band intensities for each of the western blots; the PrecisionAb Antibody shows ~5x greater signal intensity even at higher dilution. Primary antibody dilutions: PrecisionAb, 1:2,000; Competitor 1, 1:1,000; Competitor 2, 1:500. Secondary antibody dilution was 1:10,000 for all blots.

Prof. Ernesto Diaz-Flores

Results Summary: Prof. Ernesto Diaz-Flores
University of California, San Francisco

Prof. Diaz-Flores and colleagues in the Department of Pediatrics study primary patient leukemia samples to identify novel genetic alterations and incorporate them into algorithms for diagnosis, residual disease monitoring, and the identification of novel therapeutic approaches, focusing on juvenile myelomonocytic leukemia (JMML) and acute lymphoblastic leukemia (ALL)   (Holmfeldt et al. 2013). Their identification of Bcl-2 as a promising therapeutic target has led them to test specific classes of targeted Bcl-2 inhibitors in hypodiploid ALL cell lines and patient-derived xenografts.

“To test the role of Bcl-2 in cell survival as well as the effect of blocking Bcl-2 in such cells, we needed to compare cells expressing high levels of Bcl-2 against those with low Bcl-2 levels. To do so, we measured Bcl-2 levels in 12 human cell lines using the PrecisionAb BCL-2-specific antibody provided by Bio-Rad. We compared the PrecisionAb Antibody to our best commercially available Bcl-2 antibody, and the Bio-Rad antibody gave great performance at a lower concentration than our reference antibody.

For our biochemical experiments, we select high-performance reagents that give us the best signal-to-noise ratio. Bio-Rad antibodies against Bcl-2 and Bax are high-performance antibodies, as indicated by single, clean, and clear bands, with no noticeable background signal at a high dilution of 1:1,000.”

Side-by-side testing of anti-human Bcl-2 and Bax antibodies with 12 different cell lysates.

In parallel western blots, the PrecisionAb Bcl-2 Antibody showed equal or greater signal intensities even at a higher dilution; the PrecisionAb Bax Antibody performed equally well compared with the competitor antibody.