Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving viable micro-organism
Patent
1994-12-05
1997-04-29
Beisner, William H.
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving viable micro-organism
435 6, 435 40, 4352872, 4352884, 4352975, 210405, 210456, 73 6172, 7386323, 422101, C12Q 124, C12Q 108, C12M 134, C12M 112
Patent
active
056248156
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to a method of analysis, e.g. for enumerating and/or identifying microorganisms or other biological material in a liquid sample, and to apparatus for use in such a method.
BACKGROUND OF THE INVENTION
Many industries, including pharmaceuticals, need to detect low levels of materials in large volumes of liquid. For example, they rely heavily on classical microbiological techniques to detect microbial contamination. Areas often under surveillance by Quality Assurance personnel include the control of bioburden in incoming raw materials, especially liquids; monitoring of microbial population in the production environment; in-process controls, especially after storage; and final product testing. Often product is manufactured and stored whilst analysis for microbial content takes place. If contamination is detected, the product may need to be destroyed, and the production line shut down until the source of contamination is found. Often the time taken for microbial analysis is the rate-limiting factor in bringing the plant on stream. This can lead to substantial costs in wasted production or raw materials.
The determination of the number of microorganisms present in the various types of water used in a pharmaceutical environment is considered a critical factor in producing many products. Usually, the microbiological specification ranges from 0.01 to 100 cfu per ml of water, depending on the source of the sample.
Classical methods of microbe detection, whilst considered reliable and accepted in the industry, are slow and require valuable storage and laboratory space.
A test for coliform bacilli is described in "Handbook of Practical Bacteriology" 9 (1956), by T. J. Mackie and J. E. McCartney, pub. E. and S. Livingstone. The method employs a specific medium which is utilised by coliforms to release acid, and thus to give a colour change with a pH indicator. Several tubes are set up, at different dilutions, and a McCrady table is used to determine the most probable number of bacilli, from the number of positives detected. This method allows the detection of small numbers of microbes in a large volume of liquid, but involves serial dilution and an incubation stage of 48 hours.
Cherwell Laboratories Ltd., Bicester, UK, and Wilkinson and Simpson Ltd., Gateshead, UK, each produce test kits, respectively under the trade names Colitrace and Colilert, designed to test water for levels of selected organisms down to 1 per 100 ml of sample. The sample is distributed between independent tubes containing culture broths, which are then incubated; the presence of coliforms is indicated by a colour change, and E. coli can be detected by fluorescence. The most probable number (MPN) test is then used to estimate numbers of organisms.
WO-A-8202561 and also Williams et al, Annals of the New York Acad. Sci. 501:350-353 (1987), disclose methods for the detection of microorganisms in gel microdroplets with counting, using a flow microfluorimeter. The technique is difficult to operate, for a large volume of sample containing a low number of microbes.
FR-A-2649411 discloses a method for quantitative determination of bacteria, by growing them on a semi-selective medium on a membrane support. The method is unsuitable for distinguishing between species of microorganisms.
GB-A-2035372 discloses a method for quantifying coliform bacilli. In an example, a 5 ml sample is measured at a maximum rate of 0.2 ml/min. This is too slow for large sample volumes.
Pat. Abs. Japan 9(299) (P-408)(2022) (Nov. 27, 1985), equivalent to JP-A-60135862, describes a method in which a serum sample is distributed over 128 wells, and growth medium is then added. The serum titer is assayed by then counting the number of wells which are closed by cell colonies. This technique is not suitable for assaying large sample volumes.
U.S. Pat. No. 3,929,583, and subsequent literature naming A. N. Sharpe as an author, describe membrane filters for enumerating microorganisms. The then novel membrane has a grid pattern imprinted on
REFERENCES:
patent: 3929583 (1975-12-01), Sharpe et al.
patent: 4018652 (1977-04-01), Lanham et al.
patent: 4055202 (1977-10-01), Greene
patent: 4294931 (1981-10-01), Levin et al.
patent: 4493815 (1985-01-01), Fernwood et al.
patent: 5096676 (1992-03-01), McPherson et al.
patent: 5306420 (1994-04-01), Bisconte
Annals of the New York Academy of Sciences, vol. 501, 1987, pp. 350-353, G.B . Williams et al., Rapid detection of E. coli immobilized in gel microdroplets.
Evans Christopher T.
Foote Nicholas P. M.
Grant Peter L.
Noble Michael
Beisner William H.
Celsis International plc
Rauchfuss, Jr. George W.
LandOfFree
Method and apparatus for the analysis of biological material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for the analysis of biological material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for the analysis of biological material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-704926