Calcium & Other Ion Indicators

The fluorescence of SPQ is specifically quenched by chloride via collision. Therefore, chloride concentration is measured by monitoring the degree of fluorescence decrease.

TPEN (Tetrakis-(2-pyridylmethyl)ethylenediamine) is an excellent heavy metal chelator while it does not affect calcium, magnesium, sodium, or potassium concentrations. Thus, TPEN is a useful tool to identify effects of heavy metals (zinc, iron, copper, manganese, etc.) on fluorescent indicators for other ions.

Zinquin is an UV-excitable, blue fluorescent zinc indicator. Zinquin ethyl ester is membrane-permeable and is hydrolyzed into Zinquin free acid once entering cells.

Zinquin is an UV-excitable, blue fluorescent zinc indicator. Zinc is believed to be involved in the suppression of apoptosis and thought to play important roles in many neural activities.