News from the Bench
Discover what’s going on at CST, receive our latest application notes and tips, read our science features, and learn about our products.
CST Antibody Performance Guarantee
To Purchase # 3445S
|3445S||100 µl (50 tests)||$299.00.0|
Find answers on our FAQs page.
- Additional protein information
- Analytical tools
GST (26H1) Mouse mAb (Alexa Fluor® 647 Conjugate) #3445
Gallery: GST (26H1) Mouse mAb (Alexa Fluor® 647 Conjugate) #3445
Flow Cytometry, Methanol Permeabilization Protocol for Direct Conjugates
A. Solutions and Reagents
NOTE: Prepare solutions with reverse osmosis deionized (RODI) or equivalent grade water.
- 20X Phosphate Buffered Saline (PBS): (#9808) To prepare 1 L 1X PBS: add 50 ml 20X PBS to 950 ml dH2O, mix.
- 16% Formaldehyde (methanol free).
- 100% methanol.
- Incubation Buffer: Dissolve 0.5 g Bovine Serum Albumin (BSA) (#9998) in 100 ml 1X PBS. Store at 4°C.
NOTE: If using whole blood, lyse red blood cells and wash by centrifugation prior to fixation.
- Collect cells by centrifugation and aspirate supernatant.
- Resuspend cells in 0.5-1 ml 1X PBS. Add formaldehyde to obtain a final concentration of 4%.
- Fix for 15 min at room temperature.
- Wash by centrifugation with excess 1X PBS. Discard supernatant in appropriate waste container. Resuspend cells in 0.5-1 ml 1X PBS.
- Permeabilize cells by adding ice-cold 100% methanol slowly to pre-chilled cells, while gently vortexing, to a final concentration of 90% methanol.
- Incubate 30 min on ice.
- Proceed with immunostaining (Section D) or store cells at -20°C in 90% methanol.
- Aliquot desired number of cells into tubes or wells.
- Wash cells by centrifugation in excess 1X PBS to remove methanol. Discard supernatant in appropriate waste container. Repeat if necessary.
- Resuspend cells in 100 µl of diluted antibody conjugate (prepared in incubation buffer at the recommended dilution).
- Incubate for 1 hr at room temperature. Protect from light.
- Wash by centrifugation in incubation buffer. Discard supernatant. Repeat.
- Resuspend cells in 1X PBS and analyze on flow cytometer; alternatively, for DNA staining, proceed to optional DNA stain (Section E).
E. Optional DNA Dye
- Resuspend cells in 0.5 ml of DNA dye (e.g. Propidium Iodide (PI)/RNase Staining Solution #4087).
- Incubate for at least 5 min at room temperature.
- Analyze cells in DNA staining solution on flow cytometer.
posted July 2009
revised June 2017
GST (26H1) Mouse mAb (Alexa Fluor® 647 Conjugate) detects transfected glutathione S-transferase (GST) fusion proteins.Species Reactivity: All Species Expected
Monoclonal antibody is produced by immunizing animals with a GST fusion protein. This antibody was conjugated to Alexa Fluor® 647 under optimal conditions with an F/P ratio of 2-6. The Alexa Fluor® 647 dye is maximally excited by red light (e.g. 633 nm He-Ne laser). Antibody conjugates of the Alexa Fluor® 647 dye produce bright far-red-fluorescence emission, with a peak at 665 nm.
Epitope tags are useful for the labeling and detection of proteins using immunoblotting, immunoprecipitation, and immunostaining techniques. Because of their small size, they are unlikely to affect the tagged protein’s biochemical properties.
Glutathione S-transferase (GST) is a widely used fusion partner, since it provides both an easily detectable Tag and a simple purification process with little effect on the biological function of the protein of interest. Numerous vectors containing GST-Tag have been developed for both prokaryotic and eukaryotic systems over the past decade (1-3).
For Research Use Only. Not For Use In Diagnostic Procedures. Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc. The Alexa Fluor dye antibody conjugates in this product are sold under license from Life Technologies Corporation for research use only, except for use in combination with DNA microarrays. The Alexa Fluor® dyes (except for Alexa Fluor® 430 dye) are covered by pending and issued patents. Alexa Fluor® is a registered trademark of Molecular Probes, Inc.