Accession Number : ADD011832

Title :   Method and Apparatus for the Detection of Toxicants.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Hannan,P J ; Stiffey,A V ; Jarvis,N L ; Wohltjen,H

Report Date : 23 Apr 1985

Pagination or Media Count : 7

Abstract : This patent pertains to a method and apparatus for rapidly detecting toxicants via the use of a first CO2 sensing cell and a second reference CO2 sensing cell, with each sensing cell including a first chamber and a second chamber, separated by a C02 permeable membrane, and a pH sensor disposed in each of the second chambers. The method includes the step of placing distilled water in the first chamber of each cell, and allowing its dissolved CO2 to become equilibrated with the water in the second chamber, from which it is separated by the CO2 permeable membrane. Next, exact amounts of microorganism and sugar are added to small dishes in the first chambers along with control vegetation for one dish and vegetation to be tested to the other dish. Then the first chambers are completely filled with distilled water and the dishes are agitated to facilitate a solution of microorganisms and sugar. The method further includes the steps of sensing the pH in the liquid contained in each of the second chambers, determining the difference between the outputs from the pH sensors, and generating an alarm signal if this difference equals or exceeds a predetermined threshold. In one embodiment, yeast is utilized as the microorganism.

Descriptors :   *PATENTS, *TOXIC AGENTS, *BIOLOGICAL DETECTION, *DETECTORS, ELECTROLYTIC CELLS, MICROORGANISMS, CARBON DIOXIDE, GROWTH(PHYSIOLOGY), RATES, PH FACTOR, TOXIC AGENT ALARMS

Subject Categories : Toxicology
      Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE