Cal-500(TM), potassium salt

Calcium measurement is critical for numerous biological investigations. Fluorescent probes that show spectral responses upon binding calcium have enabled researchers to investigate changes in intracellular free calcium concentrations by using fluorescence microscopy, flow cytometry, fluorescence spectroscopy and fluorescence microplate readers. Cal-500(TM) is an UV-excitable calcium indicator with maximum emission at ~500 nm. It has a Stokes Shift larger than 100 nm. It can also be well excited with the 405 nm violet laser with a moderate calcium affinity of Kd ~303 nM. In CHO and HEK cells Cal-500(TM) AM has great cellular calcium response. The excitation spectra of Cal-500 is well separated from those of FITC, Alexa Fluor® 488 and GFP, making it an ideal calcium probe for multiplexing intracellular assays with GFP cell lines, FITC/Alexa Fluor® 488 labeled antibodies or other red fluorescent probes.