Documents & Support

1 - 15 of 1169 results

What is the recommended genomic DNA extraction method to be used for the CytoScan HT-CMA assay? Product FAQ

Answer

Genomic DNA extraction and purification methods that meet the general DNA requirements for this kit should yield successful results. Methods that include boiling or strong denaturants are not acceptable because the DNA would be rendered single-stranded and can no longer be accurately quantitated using a PicoGreen dye-based assay.

Answer Id:: E18681

Was this answer helpful?

Yes No

Thank you for your response

Cell-based Assay to Study Antibody-mediated Tau Clearance by Microglia. Citations & References

  • Authors: De Marco D, Taggenbrock R, Crespo R, Koudstaal W, Ramsburg E, Apetri A,
  • Journal: J Vis Exp
  • PubMed ID: 30474638

Antibody-dependent cell-mediated cytotoxicity: a flow cytometry-based assay using fluorophores. Citations & References

  • Authors: Wilkinson RW, Lee-MacAry AE, Davies D, Snary D, Ross EL
  • Journal: J Immunol Methods
  • PubMed ID: 11684135
Catalog #

Which protein assays are dye-binding based chemistries? Product FAQ

Answer

Thermo Scientific Coomassie and Coomassie Plus Protein Assay Products are variations on the use of Coomassie G-250 dye as a colorimetric reagent for the detection and quantitation of total protein first reported by Bradford in 1976. The Thermo Scientific 660 nm Protein Assay is a dye-based reagent that offers the same convenience as Coomassie-based assays while overcoming several of their disadvantages. In particular, the 660 nm Assay is compatible with most detergents and produces a more linear response curve (the detailed assay chemistry is proprietary). Our fluorometric protein assays are also based on dye binding chemistries

Answer Id:: E15550

Was this answer helpful?

Yes No

Thank you for your response

A new flow-cytometry-based opsonophagocytosis assay for the rapid measurement of functional antibody levels against Group B Streptococcus. Citations & References

  • Authors: Fabbrini M, Sammicheli C, Margarit I, Maione D, Grandi G, Giuliani MM, Mori E, Nuti S,
  • Journal: J Immunol Methods
  • PubMed ID: 22309986

What can I use for antibody blocking to prevent non-specific binding? Product FAQ

Answer

The type of blocking reagent to use is depends upon the type of application: ELISA, IHC/ICC, ISH, western blotting, microarrays, membrane- or plate-based assays, etc. Consider using commercial blocking reagents developed for specific applications.
For immunohistochemistry/immunocytochemistry, we recommend using:
- 5-10% serum diluted in PBS or other buffers (of the same species the secondary antibody was raised in).
- 2-5% BSA (use Fraction V, defatted or delipidated, antibody-free BSA) diluted in PBS or other buffers. Note: "Fraction V" is a specific method for extracting/purifying the BSA.
- Combination of 5-10% serum with 1-2% BSA.
- To limit non-specific binding of dye-labeled probes to cellular components due to the charges on the dyes, use Image-iT FX Signal Enhancer (Cat. No. I36933) as a pre-blocking step.
- If labeling with avidin/streptavidin, avoid using any blocking reagents that may contain biotin (e.g., dry milk). If using enzyme-conjugates, avoid using any blocking reagents that may contain inhibitors (e.g., the antimicrobial agent sodium azide inhibits HRP activity; chelators and inorganic phosphate can inhibit alkaline phosphatase activity).
Here are some blocking reagents we offer:
- SEA BLOCK Blocking Buffer (Cat No. 37527)
- SuperBlock (PBS) Blocking Buffer (Cat No. 37580)
- SuperBlock T20 (TBS) Blocking Buffer (Cat. No. 37536)
- Protein-Free T20 (PBS) Blocking Buffer (Cat. No. 37573)
- Protein-Free (PBS) Blocking Buffer (Cat. No. 37584)
- StartingBlock (PBS) Blocking Buffer (Cat. No. 37578)
- Fast Blocking Buffer (Cat. No. 37576)
- ReadyProbes In Situ Hybridization (ISH) Blocking Solution (Cat. No. R37620)
- eBioscience IHC/ICC Blocking Buffer - High Protein (Cat. No. 00-4952-54)
- BlockAid Blocking Solution (Cat. No. B10710)
- Clear Milk Blocking Buffer (Cat. No. 37587)

Answer Id:: E18331

Was this answer helpful?

Yes No

Thank you for your response

What are some applications of Nunc 384-Well Black or White Microplates that have a cell culture-treated surface? Product FAQ

Answer

We recommend using the Nunc 384-Well Black Microplates for cell-based assays using fluorescent detection. Viability stains such as fluorogenic esterases can be used for proliferation, toxicity, and drug resistance or sensitivity assays. Many types of fluorochrome-conjugated antibodies are available for performing cell-based immunoassays. Fluorescent reporter genes are widely used for determining cell transfection.
We recommend using the Nunc 384-Well White Microplates for cell-based assays using luminescent detection. Viability stains such as luciferin/luciferase can be used for proliferation, toxicity, and drug resistance or sensitivity assays. Cell-based immunoassays can be performed using a HRP-conjugated antibody with a luminol-based substrate. Luciferase reporter genes are widely used for determining cell transfection.

Answer Id:: E17697

Was this answer helpful?

Yes No

Thank you for your response

Brochure: Antibody- and Dye-Based Kits: Conversion of Inactivated Kits to Standalone Products Product Literature

Antibody-mediated fluorescence enhancement based on shifting the intramolecular dimer<-->monomer equilibrium of fluorescent dyes. Citations & References

  • Authors: Wei AP, Blumenthal DK, Herron JN
  • Journal: Anal Chem
  • PubMed ID: 7517105
Catalog #

Fluorescence microplate-based assay for tumor necrosis factor activity using SYTOX Green stain. Citations & References

  • Authors: Jones LJ, Singer VL
  • Journal: Anal Biochem
  • PubMed ID: 11373072
Catalog #

Which fluorochromes are recommended for antibody staining in the PrimeFlow RNA Assay? Product FAQ

Answer

Most organic and protein-based fluorochromes are compatible with this assay kit, including PE, PE tandems, APC, APC tandems, and small organic dyes such as FITC, eFluor 450, eFluor 506, eFluor 660, and Alexa Fluor 700. However, PerCP, PerCP-Cyanine5.5, and PerCP-eFluor 710 may not be used, and we recommend using PE-Cyanine5 or PE-Cyanine5.5 instead. Qdot nanocrystal and eVolve-antibody conjugates are not compatible with this assay. If Super Bright or Brilliant Violet conjugated antibodies will be utilized, please contact Tech Support at techsupport@thermofisher.com for assistance with optimizing your multicolor panel.

Answer Id:: E14578

Was this answer helpful?

Yes No

Thank you for your response

What are the advantages of one mode of detection over another for protein and enzyme activity assays? Product FAQ

Answer

The first consideration in using a specific mode of detection is availability. What modes of detection are available for an assay? Some assays are not available in one mode or another due to the chemistry of the reaction or availability of reagents for the reaction.

Secondly, does the experimental sample have color (absorbance) or autofluorescence? Some natural materials are naturally colored or fluorescent. Check your samples to see if they have a strong absorbance or absorbance over a broad range of wavelengths. This may limit your ability to use a colorimetric assay. If you are interested in a fluorescence-based assay, examine your samples, media, etc. for autofluorescence (fluorescence that is inherent to the sample due to various natural components) using all filters sets or channels available. Autofluorescent components include fluorescent proteins (GFP, etc.), porphyrins, dyes in media, some vitamins, natural pigments, etc. If a sample has high autofluorescence in a broad range of wavelengths, a fluorescence-based assay may not be compatible.

Time-resolved FRET (TR-FRET) and luminescence-based assays are desirable because endogenous sample absorbance and autofluorescence can be avoided in the detected signal. TR-FRET involves exciting the sample with defined wavelengths, turning the excitation light off and then reading emission within 50 to 100 µsec after the light has been turned off.

Luminescence-based assays, either bioluminescent or chemiluminescent assays, do not require that a sample be exposed to any excitation light; light is generated by the biological or chemical modification of the substrate.

Ratiometric assays reduce the effects of well-to-well and day-to-day variations.

Answer Id:: E15830

Was this answer helpful?

Yes No

Thank you for your response

An antibody-based microarray assay for small RNA detection. Citations & References

  • Authors: Hu Z, Zhang A, Storz G, Gottesman S, Leppla SH
  • Journal: Nucleic Acids Res
  • PubMed ID: 16614443

Antibody microarray-based profiling of complex specimens: systematic evaluation of labeling strategies. Citations & References

  • Authors: Kusnezow W, Banzon V, Schröder C, Schaal R, Hoheisel JD, Rüffer S, Luft P, Duschl A, Syagailo YV,
  • Journal: Proteomics
  • PubMed ID: 17474144
Catalog #

What is the best method for quantitating the DNA purified from the PureLink 96 Plasmid Purification System? Product FAQ

Answer

For high-throughput quantitation, a method that uses PicoGreen or Hoechst Dye 33258 is recommended. Contact Thermo Fisher Scientific Technical Support for a protocol. The Quant-iT DNA Assay Kit, Broad Range is a fluorescence-based assay that can be used for accurate quantitation of DNA as well. A Lysis Buffer component makes A260/A280 ratios unreliable. However, the component does not affect DNA sequencing, PCR, or restriction enzyme digestion.

Answer Id:: E3802

Was this answer helpful?

Yes No

Thank you for your response

Results per page
spinner