Mannitol, also known as D-mannitol, mannite, or manna sugar, is a naturally occurring sugar alcohol derived from fructose. It plays a central role in pharmaceutical, food, and laboratory settings, where it serves as an osmotic diuretic, a sugar substitute, and a tableting excipient. Its chemical formula, C₆H₁₄O₆, and molar mass of 182.17 g/mol place it among the more established polyols in industrial and research use.

What sets mannitol apart from many other sugar alcohols is its low hygroscopicity paired with mild sweetness and reliable osmotic activity. These properties make it suited to applications that demand consistency under varying humidity and processing conditions, from direct-compression tablets to dry powder inhalers. Its compatibility with a wide range of formulations and processes has made it a standard reagent across laboratory and industrial workflows alike.

Multiple supplier safety data sheets do not classify mannitol as hazardous under GHS, reflecting a favorable safety profile for routine handling. It carries recognized regulatory standing through its food additive designation, E421, and its established use in USP-grade pharmaceutical and nutraceutical products. This combination of low hazard classification and broad regulatory acceptance supports its continued demand across food, pharmaceutical, cosmetic, and industrial markets.

• Compound Name: Mannitol (D-Mannitol)

• Synonyms/Common Names: Mannite, manna sugar, hexitol, D-(-)-mannitol, 1,2,3,4,5,6-hexanehexol; pharmaceutical brand name Osmitrol; food additive designation E421

• Chemical Formula: C₆H₁₄O₆

• CAS Number: 69-65-8 (D-mannitol, primary); 87-78-5 used for mannitol with unspecified stereochemistry

• Molar Mass: 182.17 g/mol

• Appearance: White, odorless, crystalline powder or granules

Mannitol has a density of approximately 1.5 g/cm³ at 20°C, making it noticeably denser than water. In aqueous mixtures or spill scenarios, this means solid mannitol will sink rather than float, a relevant consideration for handling and cleanup planning.

Mannitol is a white, crystalline, non-hygroscopic sugar alcohol widely used in pharmaceutical, food, and laboratory applications. It functions as an osmotic diuretic, tableting excipient, and low-calorie sweetener in product and formulation contexts across these industries. U.S. laboratories and manufacturers sourcing mannitol by grade and purity contact Lab Alley at 512-668-9918 for product selection and ordering support.

Mannitol melts between 166°C and 170°C (331°F to 338°F). Rather than boiling at atmospheric pressure, it decomposes at elevated temperatures, with decomposition reported near 290°C to 295°C under reduced pressure, so thermal processing above the melting range should account for degradation rather than vaporization.

Mannitol is freely soluble in water, dissolving to approximately 182 g/L at 20°C, which supports its use in aqueous pharmaceutical and food formulations. It is only slightly soluble in methanol and ethanol and is practically insoluble in ether, limiting its utility in nonpolar extraction or formulation systems.

Aqueous solutions of mannitol typically fall between pH 5.0 and 6.5. This near-neutral range makes it compatible with most formulation and process chemistries without requiring significant pH adjustment.

Mannitol is chemically stable under normal handling and storage conditions, and multiple supplier safety data sheets do not classify it as hazardous under GHS. As a fine powder, however, it is combustible and should be handled with dust-control measures in place. It is incompatible with strong oxidizers, strong reducing agents, and alkali metals, so storage and handling should keep it separated from these materials.

Mannitol from Lab Alley is available as a crystalline powder in grades suited to pharmaceutical, nutraceutical, and laboratory applications. Packaging ranges from small laboratory bottles to bulk industrial containers to support research, manufacturing, and commercial supply needs.