Finally, we conclude that the present sensor can measure cell concentration without the accurate control and measurement of flow-rate.
Samples were withdrawn at 0, 8, 24, 48, 72 and 96 h to measure cell concentration, fluorescence (GFP) and luminescence (Gluc).
We also measure the cell concentration within the maximum concentration errors of 10.3% in two cases: (1) two different flow-rates of 5 and 0.5 μl/min, (2) the varying flow-rates from 2 to 1 μl/min, respectively.
The optical density at 600 nm was used to measure the cell concentration of the fermentation broths.
We measured the cell concentration relative to a known concentration of fluorescent beads (Fluoresbrite YG Microspheres, 3 µm; Polysciences Inc., Warrington, PA, USA) using a Cytomics TM FC500 Flow Cytometer (Beckman Coulter, Inc, CA, USA) by loading culture samples mixed with the beads.
Cell migration to the site of infection was estimated by measuring the cell concentration in hemolymph extracted from the infected muscle.
Cells were collected by centrifugation, suspended in water, the optical density at 260 nm was measured and the cell concentration determined by comparison with a standard curve.
In another study, authors demonstrated the use of magnetic beads coated with anti-E.coli O157 antibodies and streptavidin-coated QDs for measuring the bacterial cell concentration [51].
Because > 99% of lead in blood is present in red blood cells, lack of adjustment for a measure of red blood cell concentration in a population with anemia has the potential to influence blood lead level measurements (deSilva 1984; Kim and Lee 2012; Skerfving and Bergdahl 2007).
In these experimental conditions, a µmax of 0.28 h−1 was measured; resulting in a cell concentration of 2 g/L.
We have shown that total cell concentration measured with FCM is a rapid, easy, sensitive and importantly, a descriptive parameter of several widely applied drinking water treatment processes.
