Technical Support Articles

Which Phospho-p44/42 MAPK (Erk1/2) (Thr202/Tyr204) antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) with mouse samples?

We have several monoclonal antibodies for detecting p44 and p42 MAPK when phosphorylated at Thr202 and Tyr204 of Erk1, or Thr185 and Tyr187 of Erk2, that are validated for IF-IC with mouse samples. Th...

Why do I need to use the three buffers in the Cell Fractionation Kit #9038?

Each buffer in the Cell Fractionation Kit #9038 contains detergents to help isolate different cellular fractions. The Cytoplasmic Isolation Buffer (CIB) contains a non-ionic detergent used as a cell p...

Does CUT&RUN show a bias toward euchromatin or heterochromatin?

We do not observe any bias toward euchromatin or heterochromatin in our assays. In CUT&RUN, the target-specific antibody recruits the pAG-MNase and directs digestion to chromatin that is directly ...

Does this antibody work for my application (western blot, immunoprecipitation, immunofluorescence, immunohistochemistry, ELISA, flow cytometry, chromatin immunoprecipitation, etc.)?

CST routinely tests antibodies in relevant applications. Those that pass rigorous application-specific validation standards are recommended. We only recommend applications that have passed rigorous va...

Why is the concentration of my antibody so low?

At CST, our antibodies are formulated on the basis of their reactivity and performance for each approved application at a recommended dilution. For antibodies with high affinity, optimal performan...

What controls should I include when performing a Simple Western™ experiment?

In addition to a known positive control sample, we recommend the following negative controls for your Simple Western™ experiment.

1. A no lysate control. This includes the primary antibody at t...

Why do my Concanavalin A Magnetic Beads #82307 appear aggregated?

As long as your Concanavalin A Magnetic Beads #82307 have been stored at the appropriate recommended temperature, the appearance of aggregation is not a cause for concern. By nature, the bead particle...

Why do I see a doublet with my beta-Actin antibody?

It is not uncommon to see a doublet with our beta-Actin antibodies depending on the samples being tested. It is likely caused either by phosphorylation of beta-Actin on its many phosphorylation sites,...

How were the sequences of the PTMScan® Control peptides chosen?

The sequences of the synthetic peptides were based on modified peptides that we have consistently recovered and identified in human and mouse samples during our inte...

Which cleaved PARP antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) in human samples?

We have several antibodies for detecting cleaved PARP that are validated for IF-IC with human samples. These are Cleaved PARP (Asp214) (D64E10) XP® Rabbit mAb #5625 and Cleaved-PARP (Asp214) (E2T4K) M...

Which Cas9 antibody is the most sensitive by western immunoblot?

The most sensitive antibody will depend on whether you are trying to detect Cas9 protein from Streptococcus pyogenes, Staphylococcus aureus, or Campylobacter jejuni. The Cas9 (7A9...

Will the Non-phospho (Active) YAP (Ser127) (E6U8Z) Rabbit mAb #29495 cross-react with TAZ?

YAP and TAZ are co-expressed abundantly in every cell line that has been shown to be positive for either protein, and likewise, they are negative/low in the same cell lines (essentially, they appear t...

Can the Lambda Protein Phosphatase Kit #89726 be stored at -20°C?

The Lambda Protein Phosphatase #56206 included in the Lambda Protein Phosphatase Kit #89726 is temperature sensitive. Therefore, we recommend storing the kit at -80°C. However, the kit is stable at -2...

Is the “Best By” date the expiration date for the product? Will the product still work after that date?

Our products can be expected to perform at optimal levels up until the printed "Best" by date on the vial when stored under the recommended conditions. Many of our products will work well af...

Are any of your SARS-CoV-2 Spike Proteins suitable for cell culture?

Unfortunately, we have not tested our SARS-CoV-2 Spike Proteins in cell culture. Additionally, these products are not sterile, therefore we would not recommend using them in this manner. 

Do I need to optimize the Tn5 tagmentation conditions for different cell types when performing CUT&Tag?

Our optimized tagmentation conditions for the CUT&Tag assay work well across multiple cell lines, both adherent and suspension. We recommend using 2 μL of CUT&Tag pAG-Tn5 (Loaded) #79561 in...

Which isotype control should I use for IHC?

For mouse IgGs, you will need to determine the isotype of the primary antibody and use the appropriate isotype control:
IgG1: Mouse (G3A1) mAb IgG1 Isotype Control #5415
IgG2a: Mouse (E5Y6Q) mAb...

Do any of your GFP antibodies recognize ZsGreen and/or copGFP?

Regrettably, none of our GFP antibodies will recognize ZsGreen and copGFP.

What procedure do you recommend for antigen retrieval with EDTA?

We recommend using a microwave to bring slides to a boil in 1 mM EDTA, pH 8.0 followed by 15 minutes at sub-boiling temperature. Typically the power level must be adjusted during the 15 minute period ...

What controls can I use to show my CUT&RUN experiment is working?

When using antibodies for CUT&RUN against histone modifications, we typically see fragment sizes as small as 150 bp (size of a mono-nucleosome) and quite often see a nucleosomal ladder of DNA frag...