Calcium imaging Calcium imaging Calcium imaging is a scientific technique usually carried out in research which is designed to show the calcium (Ca) status of an isolated cell, tissue or medium. Calcium imaging techniques take advantage of so-called calcium indicators, fluorescent molecules that can respond to the binding of Ca ions by changing their fluorescence properties. Two main classes of calcium indicators exist: chemical indicators and genetically encoded calcium indicators (GECI). Calcium imaging can be used to optically probe intracellular calcium in living animals. This technique has allowed studies of calcium signalling in a wide variety of cell types and neuronal activity
Calcium citrate Calcium citrate Calcium citrate is the calcium salt of citric acid. It is commonly used as a food additive (E333), usually as a preservative, but sometimes for flavor. In this sense, it is similar to sodium citrate. Calcium citrate is also found in some dietary calcium supplements (e.g. Citracal). Calcium makes up 24.1% of calcium citrate (anhydrous) and 21.1% of calcium citrate (tetrahydrate) by mass. The tetrahydrate occurs in nature as the mineral Earlandite. Calcium citrate is sparingly soluble in water. Needle-shaped crystals of tricalcium dicitrate tetrahydrate [Ca(CHO)(HO)]·2HO were obtained by hydrothermal synthesis. The crystal structure comprises a three-dimensional network