Overview
Anhydrous D-Mannitol is a polyol (sugar alcohol) derived from hydrogenation of fructose or extracted from seaweed. It is a stereoisomer of sorbitol and exists as a white, odorless crystalline powder with a sweet taste. As a non-hygroscopic compound, it maintains stability under various environmental conditions, making it valuable in moisture-sensitive formulations. The substance holds GRAS (Generally Recognized As Safe) status from the FDA and is widely used across industries due to its inert properties and compatibility with other ingredients. Its unique ability to form chelates with metallic ions adds to its versatility in specialized applications.
Physical and Chemical Properties
Anhydrous D-Mannitol exhibits a melting point range of 165-169°C and decomposes at higher temperatures rather than boiling. Its crystalline structure contributes to a density of 1.52 g/cm³ and low hygroscopicity, distinguishing it from similar polyols like sorbitol. The compound shows moderate water solubility (13 g/100 mL at room temperature) with endothermic dissolution, a property utilized in chewable tablet formulations. Chemically, it demonstrates remarkable stability, resisting reduction and oxidation under normal conditions. The six hydroxyl groups in its structure enable hydrogen bonding, affecting its crystalline properties and solubility characteristics. These properties make it particularly useful as a non-reactive excipient in pharmaceutical preparations.
Main Applications
In pharmaceuticals, anhydrous D-Mannitol serves as a key excipient in tablet formulations, especially chewable and orally disintegrating tablets, where its negative heat of solution provides a cooling sensation. It functions as a diluent, sweetener, and stabilizer in vaccine freeze-drying processes. The compound's osmotic properties make it valuable in diagnostic preparations for renal function tests. The food industry utilizes it as a low-calorie sweetener (about 60% as sweet as sucrose) in sugar-free products, with the added benefit of not promoting tooth decay. Industrial applications include use as a starting material for surfactants and as a dusting powder in the manufacture of rubber products. Its chemical inertness also makes it suitable for use in electrolytic capacitors.
Safety and Storage
Anhydrous D-Mannitol is classified as practically non-toxic with an LD50 of 13.5 g/kg (oral, rat). While generally safe, excessive consumption may cause osmotic diarrhea or mild gastrointestinal discomfort due to incomplete absorption in the small intestine. Occupational exposure limits have not been established as significant risks are not anticipated with normal handling. Proper storage involves keeping containers tightly closed in a cool, dry place at temperatures below 30°C. Although non-hygroscopic, prolonged exposure to high humidity should be avoided. The material is stable under normal conditions but may form electrostatic charges when handled in powder form, requiring appropriate grounding during large-scale processing.
B2B Procurement Guide
When procuring anhydrous D-Mannitol, buyers should specify the required pharmacopeia standard (USP, EP, or JP) if for pharmaceutical use. Key quality parameters include purity (typically ≥98%), residual solvents, heavy metal content, and microbiological limits. For food applications, verify compliance with appropriate food additive regulations (e.g., FCC, E421). Consider ordering from manufacturers with ISO 9001 certification and request certificates of analysis for each batch. Bulk purchases (ton quantities) typically offer significant cost advantages, with prices varying based on purity, packaging, and quantity. For critical applications, audit the supplier's quality control procedures and request stability data to ensure product consistency.