Calcein Blue, AM is a cell-permeant esterase substrate that can serve as a viability probe that measures both enzymatic activity and cell-membrane integrity, which is required for intracellular retention of their fluorescent product. Calcein blue AM is only weakly fluorescent (excitation/emission maxima ~322/435 nm). Upon cleavage of the AM esters by intracellular esterases, this tracer becomes relatively polar and is retained by cells for several hours. In addition, its fluorescence intensity increases and its fluorescence spectra shift to longer wavelengths, with excitation/emission maxima of ~360/449 nm. This dye is provided as 1 mg solid (C022) and 1 mg/mL solution in DMSO (C023).
Specifications: | ||
Excitation/Emission: | 360/449 nm (after cleavage) | |
Shipping Condition: | Ice pack | |
Storage Conditions: | -20ºC, protect from light | |
Molecular Formula: | C21H23NO11 | |
Molecular Weight: | 465.41 | |
CAS Number: | 168482-84-6 | |
Protocol (PDF): | C022 | C023 |
MSDS (PDF): | MSDS-C022 | MSDS-C023 |
COA (PDF): | C022 | C023 |
Reference:
Bernhard JM, Newkirk SG, Bowser SS
J Euk Microbiol (1995) 42:357-357
J Biol Chem (2003) 278:8286-8293
Science (1991) 251:81-85
Frequently Asked Questions (FAQs)
I need a general cytoplasmic stain that does not overlap with the GFP in my cells. What do you recommend?
Calcein AM, a green dye, is typically used as a general cytoplasmic stain, but not recommended with GFP-positive cells. For GFP-expressing cells, Calcein Blue AM is recommended for general cytoplasmic stain. The retention time of these dyes in live cells is dependent upon the inherent properties of the cell.
I want to do a cell migration study for around 4 hours and need to fluorescently label the cells with a dye. What do you recommend?
Calcein, AM and FDA (fluorescein diaceate) are examples of some dyes used for this application. Since these dyes are not incorporated or covalently attached to any cellular components, they may have a short retention time as some cell types may actively efflux the dye out of the cells. The CellView™ dyes and CFDA, SE include either a mild thiol-reactive chloromethyl group or amine-reactive succinnimidyl ester group to allow for covalent binding to cellular components, providing for better retention.