eBioscience™ Indo-1 AM Calcium Sensor Dye

Indo-1 AM Calcium Sensor Dye is a membrane-permeable dye used for determining changes in calcium concentrations in the cell using fluorescence microscopy, flow cytometry, fluorescence spectroscopy and fluorescence microplate readers. Once Indo-1 enters the cell, esterases cleave the AM group yielding a membrane-impermeable dye. Unbound Indo-1 has a peak emission at 475 nm. Upon binding calcium, the peak emission shifts down to 410 nm.

In flow cytometry this can be measured over time and can be represented as a ratio of the two emission wavelengths. To optimize the ratio between the two emissions, unbound Indo-1 fluorescence should be collected using a filter above 485nm (525 nm is a good option) while bound Indo-1 fluorescence should be collected using a filter below 400 nm. Because the emission profile of Indo-1 is broad, multicolor flow analysis using eFluor ™ 450, eVolve™ 605 or eVolve™ 655 is not possible, however fluorochrome conjugated antibodies utilizing the 488nm or 633 nm are quite compatible with Indo-1.

Molecular Weight: 1009.91
Peak Excitation: 346 nm
Peak Emission: 475 nm

Indo-1 AM should be reconstituted in high-quality, freshly opened DMSO. Recommended concentration: 1 mM.
Once reconstituted, it should be protected from light and stored at -20°C; avoid freeze-thaws.

Purity
>90% by HPLC

Reported Application
Flow Cytometric Analysis, Microscopy, Immunohistochemical Staining