FAQs
What does USP grade mean for mannitol?
USP grade mannitol meets the United States Pharmacopeia monograph, which includes a melting range of 164 to 169 °C, a specific rotation of +137 to +145 degrees, a loss on drying of no more than 0.3%, and a reducing sugar test. It suits formulation and regulated lab work.
What is mannitol used for in the lab?
It is used as a bulking agent in freeze-drying, a fermentable carbohydrate in microbiology media such as mannitol salt agar, a non-hygroscopic diluent in formulation work, and a complexing agent that allows boric acid to be titrated sharply with sodium hydroxide. It is a versatile reagent.
How is mannitol different from sorbitol?
Mannitol and sorbitol are isomers with the same formula. Mannitol absorbs little moisture and is less soluble in water, while sorbitol is hygroscopic and highly soluble. Those differences make mannitol the preferred choice for dry tablets and freeze-dried cakes. Both are sugar alcohols used widely in formulations, but they are not interchangeable in dry products.
Why is mannitol used in freeze-drying?
Mannitol crystallizes during freezing and forms a firm, porous cake that supports the dried product and dissolves quickly when reconstituted. Its low moisture uptake also helps the dried product remain stable during storage. Typical formulations combine mannitol with other excipients, and the freezing protocol controls how completely it crystallizes during processing.
Can this mannitol be used for injection?
No. This product is supplied for laboratory and manufacturing use. Medical mannitol injections are separate sterile products made and tested under drug manufacturing controls. Use this material for research, formulation development, media, and analytical work. Label stock clearly so laboratory material stays separate from any clinical supplies in shared areas.
