Microprecipitation of nanoparticulate pharmaceutical agents using surface active material derived from similar pharmaceutical agents
US5716642A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 10, 1995 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Jan 10, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/915
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
This invention describes the preparation of nanoparticulate pharmaceutical agent dispersion via a process that comprises the dissolution of the said pharmaceutical agent in an alkaline solution and then neutralizing the said solution with an acid in the presence of suitable surface-modifying, surface-active agents to form a fine particle dispersion of the said pharmaceutical agent. A combination of surface active surface modifying agents comprising a nonionic surface active substance and an anionic surface active material having a chemical structure which is at least on a molecular basis 75% similar to the pharmaceutical agent is used. This process is preferably followed by steps of diafiltration clean-up of the dispersion and then concentration of it to a desired level. This process of dispersion preparation leads to microcrystalline particles of Z-average diameters smaller than 400 nm as measured by photon correlation spectroscopy. Various modifications of precipitation schemes are described, many of which are suitable for large-scale manufacture of these agent dispersions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.