Indicators

Chemical indicators are reagents that produce a detectable signal upon exposure to certain chemicals or changes in the chemical environment. The indication typically occurs as a change in color or emission of fluorescence. Indicators for calcium (Rhod-2, Fura-2, Indo-1), chloride (SPQ, MQAE), zinc (zinquin, fluozin), sodium and magnesium are often used in measuring intracellular ion levels for various cellular studies. pH indicators (SNARF, BCECF) are also available for measuring the acidity of the cellular environment.