Method of preparing a rapidly dissolving powder of crystalline cephalothin sodium for parenteral administration
US4132848A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1977 |
| Grant date | Jan 2, 1979 |
| Priority date | — |
| Expiry date | Nov 3, 1997 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K31/545
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Essentially crystalline cephalothin sodium for parenteral administration is prepared by a freeze-drying process wherein a (C.sub.1 -C.sub.3 alcohol or acetone)-water solution of cephalothin sodium containing from about 2 to about 10 percent of C.sub.1 -C.sub.3 alcohol or acetone by volume is chilled from room temperature to -20.degree. C., or below, preferably about -40.degree. C. over a 1-3 hour period and then warmed to from about -3.degree. C. to about -10.degree. C. and held for 3 hours or more, then cooled to -20.degree. C., or below, preferably about -40.degree. C., before subjecting said frozen solution to a high vacuum and a moderate amount of heat to sublime the frozen solvent therefrom. The resulting powder dissolves rapidly in acceptable pharmaceutical diluents. Alternatively, from about 2 to about 5 percent by weight of sodium bicarbonate, related to the amount of cephalothin sodium present, is added to the solution before freeze-drying.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.