Study on polymerization of the pharmaceutical substances isohexenylnaphthazarins
β Scribed by A. N. Assimopoulou; V. P. Papageorgiou
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 190 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0269-3879
- DOI
- 10.1002/bmc.344
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β¦ Synopsis
Abstract
Polymerization of naturally occurring isohexenylnaphthazarins (IHN), such as alkannin, shikonin (A/S) and their derivatives, which are potent pharmaceutical substances, signiο¬cantly affects their use in pharmaceuticals, cosmetics and as food colorants, because it leads to reduction of the lustre of their red coloration, a decrease in their solubility and reduces the active monomeric IHN derivatives. In the present study, the inο¬uence of several crucial variables (processing and storage) was experimentally investigated on IHN polymerization by size exclusion chromatography (SEC). Temperature and solvent polarity increased signiο¬cantly the concentration of hydroxynaphthoquinone (HNQ) polymers, while air and light exposure conditions did not signiο¬cantly affect IHN polymerization. Low temperatures are proposed for all processes of industrial production of pharmaceutical preparations containing IHN and HNQ. An optimization of the industrial conditions used for the preparation of pharmaceutical and cosmetic preparations containing IHN, maximizing the active monomeric IHN fraction, was performed. Copyright Β© 2003 John Wiley & Sons, Ltd.
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