Patent · US Expired

Process and apparatus for ascertaining the concentration of microorganism in a water specimen

US4018652A · kind A · utility

162Cited by
1References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 9, 1976
Grant dateApr 19, 1977
Priority date
Expiry dateJan 9, 1996

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S435/885
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The concentration of microorganisms in a known volume of a water specimen is ascertained by introducing the water specimen into a plurality of wells which have known volume and contain a nutrient medium. The mixture of water specimen and nutrient medium is incubated and the wells are observed for a change in the appearance thereof which indicates metabolic activity, that is, the existence of microorganisms in the wells. If all the wells change appearance, then it is known that the concentration exceeds a certain limit, that is, at least one cell per specific well volume. On the other hand, if none of the wells change, then it is most likely the concentration is less than one cell per total volume of specimen in the wells. A change in appearance of some but not all of the wells indicates a concentration between the foregoing limits, and this concentration is estimated by statistical evaluation based on proven statistical computations.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.