Linear Formula: MgSO4 · 7H2O, Molecular Weight: 246.47, BioReagent, for molecular biology, suitable for plant cell culture, ≥99.0%, Synonym: Epsom salts. Magnesium sulfate heptahydrate has been used: in the preparation of Scott′s tap water substitute as a bluing reagent for nuclear staining, as a component of stabilization solution for the isolation of pituitary cells for matrix-assisted laser desorption/ionization mass spectroscopy (MALDI-MS), and as an additive in the preparation of artificial sea water for the maintenance of Aplysia californica and in modified Gey′s balanced salt solution.