J. Lappalainen et al., Automated color correction method for Vibrio fischeri toxicity test. Comparison of standard and kinetic assays, CHEMOSPHERE, 45(4-5), 2001, pp. 635-641
We demonstrate in this study that the toxicity of solid and highly colorful
samples can be measured with kinetic bioassay using luminescent bacterium
Vibrio fischeri. The Flash assay, named after the test protocol, is perform
ed with a tube luminometer. In this method, each sample acts as a reference
for itself, and therefore, the color correction is possible with minimal h
ands-on-time. The bacteria are dispensed into the sample and the signal is
recorded continuously. The maximum signal received after immediately dispen
sing is compared to the signal after an incubation period. With many chemic
als, the toxic effects are obtained after a very short contact time. Howeve
r, different chemicals have different modes of toxicity. Thus, kinetic data
from sample analyses after 15 or 30 min for this bacterium gives an additi
onal dimension for obtaining reliable results. The performance of the test
was compared to the standardized photobacteria test protocol with reference
chemicals. The repeatability of the test was excellent. The coefficient of
variation was normally below 1% with 10 replicates. (C) 2001 Elsevier Scie
nce Ltd. All rights reserved.