Cell Count for Low Concentration Samples

How to use Micro Counter with low concentraton samples?

What is cell counting?

From a statistic point of view, cell counting is sampling an existing population (the original concentration), performed by taking a reduced amount of the population (the counting sample) in order to estimate the original population. So, the main problem with low concentration is that the sample taken will be too small to accurately guess the original concentration.

So what are the consequences of the sample being too small?

If the sample is too small, the given results would oscillate too much around the real concentration.


Fig. 1. Small Sample (15 cells per count) Fig.2. Large Sample (150 cells per count)

In Figure 1, we see 10 cell counts performed from an original concentration of 1 x 106 cells / ml, taking 15 cells for each count.

So what can be done?

There are several things that we can do in order to obtain a reliable measure for low concentration samples with Micro Counter. Some of them can also be applied when performing a manual cell counting with a Neubauer chamber and a microscope.

Solution Min. Concentration
Change microscope objective 250.000 cells / ml
Take more microscope fields 62.500 cells / ml
Deeper chamber 7.000 cells / ml
96-well plate 250 cells / ml

 

« 12345»