Technical Support Articles

Results (690)

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...

How should I resuspend and aliquot the PTMScan® LysC Protease #84748?

To resuspend the PTMScan® LysC Protease #84748, we recommend allowing the vial to equilibrate at room temperature for a few minutes after removing from the -20C freezer. Next, spin the vial at 1,0...

Do you have human-reactive antibodies available for SignalStar™ Multiplex IHC?

Yes, please select “Human” in the first step of the SignalStar Multiplex IHC Panel Builder ...

Can you provide data that confirms the specificity of your Raptor (24C12) Rabbit mAb #2280?

The specificity of our Raptor (24C12) Rabbit mAb #2280 has been confirmed by siRNA in the following papers:

PMID: 28648777 (https://pubmed.ncbi.nlm.nih.gov/28648777/) Figure 2B

PMID: 249...

How stable is the Senescence β-Galactosidase Staining Kit #9860 after multiple freeze/thaws?

We are confident that the Senescence β-Galactosidase Staining Kit #9860 will continue to perform as expected up to at least 3 freeze/thaw cycles. We recommend aliquoting your reagents into single use ...

How are the SignalStar™ Multiplex IHC Kits & Reagents validated?

CST thoroughly validates each antibody available in the

Can I modify the CST-recommended protocol for a given application?

CST antibodies undergo thorough validation processes to ensure reliable performance for every approved application. This includes testing different protocol variations to identify the most effective o...

Which β-actin antibody do you suggest for immunofluorescence-immunocytochemistry (IF-IC) in human samples?

We have several antibodies for detecting β-actin that are validated for IF-IC with human samples. These include:

β-Actin (13E5) Rabbit mAb #4970

β-Actin (D6A8) Rabbit mAb #...

Can I reuse PTMScan® antibody beads?

The “classic” PTMScan® kits that use agarose beads and the PTMScan HS kits that use magnetic beads are both designed for a single PTM peptide enrichment. The nature of the acidic elution step, which l...

Can I use primers from the Illumina Nextera Library preparation system or design my own primers to amplify the DNA library generated from the CUT&Tag Assay Kit #77552??

Yes, you can use primers from the Illumina Nextera Library preparation system or self-designed primers to amplify the DNA library generated from the CUT&Tag DNA using the CUT&Tag Assay Kit #77...

When comparing my SignalStar™ staining to the chromogenic staining on a serial section, I see more positive cells. How do I know if this excess staining is correct?

During the course of optimization, we’ve found that fluorescent staining may show higher %-positivity than chromogenic staining. To ensure any excess staining is specific, confirm that the correct sub...

Should I be concerned that my Concanavalin A beads "clump together" in some of my CUT&RUN experiments?

The Concanavalin A beads can clump together rather easily, especially when the cells become lysed. To avoid this, make sure your cells are healthy and be sure to treat them very gently during the cell...

What is an appropriate positive control to include in this SignalStar™ assay? Are multiple controls necessary?

Any tissue shown to be positive for each marker via chromogenic IHC can serve as a positive control tissue for a SignalStar™ assay. Each target will therefore require a positive control, which may som...

Which cleaved caspase-3 (Asp175) antibody do you suggest for paraffin-embedded immunohistochemistry (IHC-P) with mouse samples?

We have several antibodies for detecting caspase-3 when cleaved at Asp175 that are validated for IHC-P with mouse samples. These are:

Cleaved Caspase-3 (Asp175) Antibody #9661

Cleaved ...

Can the Cell Fractionation Kit #9038 be used for frozen cell pellets?

We have had customers perform this assay using frozen cell pellets, prior to adding any fractionation buffer, and the subsequent fractionation worked fine. Once you start fractionating, we recommen...

In terms of cytokine activity, what is the difference between International Units (IU) and specific activity?

International Units (IU) and specific activity are two different ways of measuring...

Why is the PTMScan® LysC Protease #84748 digestion performed at room temperature and not at 37°C?

The digestion is performed at room temperature to minimize carbamylation (also known as carbamoylation) of the sample peptides in the urea buffer, which can interfere with downstream PTMScan enrichmen...

How does the specificity of the F(ab’)2 fragments differ from the corresponding full-length monoclonal antibodies?

Since the paratopes of the antibody fragments are identical to that of the corresponding full-length monoclonal antibodies, their specificity for scFv linkers remains unchanged. However, the abs...

Can CUT&Tag-enriched DNA be analyzed by qPCR, or do I have to do NGS to analyze my data?

If qPCR analysis is desired, we recommend performing CUT&RUN, as CUT&Tag DNA is not compatible with qPCR. The sample incubation step at 58℃ required for tagmented DNA solubilization in the ...

How do the Phospho-Tyrosine Mouse mAb (P-Tyr-100) #9411 and the Phospho-Tyrosine (P-Tyr-1000) MultiMab™ Rabbit mAb mix #8954 compare in terms of their sensitivity and specificity?

The Phospho-Tyrosine Mouse mAb (P-Tyr-100) #9411 is a mouse mAb from a single clone, whereas the Phospho-Tyrosine (P-Tyr-1000) MultiMab™ Rabbit mAb mix #8954 is a mix of rabbit mAbs from multiple clon...

Which phospho-S6 ribosomal protein (Ser235/236) antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) with human samples?

We have several antibodies for detecting the phosphorylation of ribosomal protein S6 (rpS6) at Ser235/236 that are validated for IF-IC with human samples. These are as follows:

Phospho-S6 Ribo...
Can I order a custom formulation of an antibody?

For custom (carrier-free) orders, many antibodies are available pre-formulated in PBS without BSA or glycerol. This carrier-free formulation is amenable to conjugation and can be conjugated to fluorop...
Which p44/42 MAPK (Erk1/2) antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) with mouse samples?

We have several monoclonal antibodies for studying p44 and p42 mitogen-activated protein kinases (MAPKs), also referred to as Erk2 and Erk1, that are validated in IF-IC with mouse tissues. These are p...
Which cleaved caspase-3 (Asp175) antibody do you suggest for paraffin-embedded immunohistochemistry (IHC-P) with human samples?

We have several antibodies for detecting caspase-3 when cleaved at Asp175 that are validated for IHC-P with human samples. These are:
- Cleaved ...
  What is the solution formulation of the PTMScan Control peptides?
  
  The solution formulation of the PTMScan Control peptides is 25% acetonitrile, 74.9% water, 0.1% trifluoroacetic acid (V:V).
  
  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...
  Is there a maximum number of cells that can be used in a single CUT&Tag assay?
  
  We have found 100,000 cells per assay to be sufficient for enriching target loci for multiple histone modifications, transcription factors, and transcription cofactors. However, one can increase the n...
  How is the PTMScan® HS Ubiquitin/SUMO Remnant Motif (K-ε-GG) Kit #59322 different from traditional, agarose bead PTMScan®?
  
  The PTMScan® HS Ubiquitin/SUMO Remnant Motif (K-ε-GG) Kit #59322 uses the same antibody as in the traditional PTMScan Ubiquitin Remnant Motif (K-ε-GG) Kit #5562 and PTMScan Pilot Ubiquitin Remnant Mot...
  Does your CUT&RUN Assay Kit work with isolated nuclei?
  
  Our CUT&RUN Assay Kit is optimized for use with whole cells and works with a large number of cell lines, both adherent and suspension. While it is not typically necessary to pre-isolate cell nucle...
  Which cleaved caspase-3 (Asp175) antibody do you suggest for immunofluorescent immunocytochemistry (IF-IC) with human samples?
  
  We have several antibodies for detecting Cleaved Caspase-3 (Asp175) that are validated for IF-IC with human samples. These are:
  - Cleaved Caspas...