Determine initial concentration

We determine the concentration immediately after inoculation, T₀, to know the starting concentration. This number will help compare post-incubation results to determine if cell concentration has increased.

The target seeding concentration is 1 × 10⁷ cells/mL and therefore a 1:100 dilution will usually be suitable to hit the BactoBox® working range.

Step by step

1

Pull a sample at T0

Use a sterile serological pipette to collect 1 mL sample immediately after inoculation and swirling. Transfer to a 5 mL centrifuge vial.

2

Disaggregate cell clumps

Vortex the sample 1 min at max speed to disaggregate cell clumps.

3

Dilute 1:100

Transfer 101 µL of T0 culture to 10 mL of diluent. Vortex 10 sec. at max speed.

4

Measure

Transfer tubing kit to the diluted sample. Press Measure and wait for the result to appear on the BactoBox® screen.

5

Calculate concentration

Multiply the cells/mL result with the dilution factor, in this case 100, to get the cell concentration in the culture at T₀.

6

Incubate

Place the shake flask at desired growth conditions.

Summary

Now that concentration at T₀ is known, proceed to Determine concentration after incubation.