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Development of a tape transport bacterial detection systemThe feasibility of a tape transport chemiluminescence system for bacterial monitoring of regenerated water was demonstrated using a manually operated laboratory breadboard. The principle of detection is based on measuring the increase in chemiluminescence produced by the catalytic action of bacterial porphyrins on a luminol-hydrogen peroxide mixture. Viable organisms are distinguished from nonviable by comparing the signals of incubated and unincubated water samples. Using optimized protocols, sensitivities were obtained with 400 ml suspensions of E. coli and Cl. sporogenes. The sensitivity of the unincubated cycle E. coli (aerobe) was found to be 30 to 35 cells/m1, and that of the Cl. sporogenes (anaerobe) was 1000 to 10,000 cells/m1. The lower sensitivity toward Cl. sporogenes is attributed to several factors, namely the lower cytochrome content, the tendency to sporulate, long lag periods and the lower growth rate of Clostridia in general. The operational procedures used for processing the incubated and unincubated samples involved the following sequence: (1) concentrating the sample by filtration through a membrane filter, (2) washing with Dextrose-Thioglycollate Broth (3) incubating (0 to 4 hrs as required), (4) washing with 4M Urea, and (5) reacting with reagent in front of a photomultiplier tube. The signal output was recorded on a strip chart recorder.
Document ID
19720011443
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Witz, S.
(Aerojet Medical and Biological Systems El Monte, CA, United States)
Hartung, W. H.
(Aerojet Medical and Biological Systems El Monte, CA, United States)
Date Acquired
August 6, 2013
Publication Date
February 25, 1972
Subject Category
Biosciences
Report/Patent Number
REPT-1102F
NASA-CR-115457
Accession Number
72N19093
Funding Number(s)
CONTRACT_GRANT: NAS9-11644
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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