Salt hydrate particles

Salt hydrate particles are crystalline solids composed of an inorganic or organic salt and a specific number of water molecules integrated into the ionic lattice. In pharmaceutical science, these particles are a critical solid-state form of many active pharmaceutical ingredients (APIs), where the hydration state—such as monohydrate or trihydrate—profoundly influences the drug's solubility, dissolution kinetics, and physical stability [13]. Beyond medicine, salt hydrate particles are extensively researched for thermochemical energy storage (TCES), serving as 'heat batteries' that absorb and release energy through reversible hydration and dehydration cycles [3, 8, 14]. Despite their importance in drug delivery and engineering, salt hydrate particles are not therapeutic targets like receptors or enzymes. They represent a physical state or formulation vehicle for chemical compounds rather than a site of biological drug action [10, 12].

Other names

Hydrated salt particlesCrystalline salt hydratesThermochemical materials (TCMs)Inorganic hydrate particlesSalt-water crystal compounds

Salt hydrate particles do not possess a biological mechanism of action; in pharmacology, they serve as a specific physical form of a drug to optimize bioavailability and stability [6, 13].