Patent · US Expired

Purification of chemically modified cyclodextrins

US5569756A · kind A · utility

30Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 21, 1995
Grant dateOct 29, 1996
Priority date
Expiry dateMar 21, 2015

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08B37/0012
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Chemically modified cyclodextrins such as hydroxypropyl cyclodextrins are purified by treatment with an activated carbon made from either coal or coconut shells. The amount of activated carbon used is 50% to 300% by weight of modified cyclodextrin. The treatment removes organic impurities such as glycol introduced during the chemical modification process of the cyclodextrin. The treatment step is conducted by passing an aqueous solution of the unpurified modified cyclodextrin through a column packed with the activated carbon or by adding the activated carbon to a container of the unpruified modified cyclodextrin and mildly agitating the contents of the container to remove the impurities.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.