Method for reducing blood carbon dioxide background in bacterial media by the addition of micelles of saponin and a phospholipid
US4994378A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1989 |
| Grant date | Feb 19, 1991 |
| Priority date | — |
| Expiry date | Sep 8, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12Q1/04
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
A non-ionic lytic agent, preferably saponin for reducing the background carbon dioxide produced by blood cell metabolism is used in the testing of cultures for the presence of microorganisms. The hemolytic agent saponin is combined with a phospholipid, preferably L-.alpha.-Lecithin (phosphatidylcholine), to form mixed micelles which protect saponin from the effects of heat sterilization and high blood cholesterol levels, thus maintaining the lytic activity of saponin. The phospholipid/saponin mixed micelles are added to non-radiometric culture media vials such as Bactec.RTM. NR6A, NR7A and NR8A. The media vials are used in the Bactec.RTM. NR-660 and NR-730 instruments. However, the present invention may also be used in radiometric media such as Bactec.RTM. culture vials 6, 7 and 8 for reducing background carbon dioxide levels detected in C.sup.14 radiometric instruments such as the Bactec.RTM.-460, or in other instruments designed to detect bacteria in the presence of mammalian cells by monitoring the increase in CO.sub.2 produced by the metabolizing bacteria.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.