5 replies to this topic

[Geraldo Oliveira]

Hi,

I have been growing Sf9 cells in suspension culture medium using TNM-FH-10% FCS and glass Erlenmeyer flasks.

When I use 125 ml Erlenmeyer flask with 25 mL of culture medium, I observe the formation of a ring of cells on the wall of the flask at the interface between air and culture medium. However, the cell growth and viability sounds good.

When I use 250 ml Erlenmeyer flasks with 50 ml of culture medium, the ring of cells become more prominent and, sometimes, the cells in the ring start to die.

What should I do to prevent death of cells in the ring or the formation of the ring altogether?

Thank you,

Geraldo Oliveira.

[pDNA]

we use Fernbach flasks instead of erlenmeyer flasks for insect culture.

Regards,
p

[Geraldo Oliveira]

Hi,

Are Fernbach flasks made of polycarbonate?

Have you ever compared growing Sf9 cells in Fernbach and Erlenmeyer flasks?


Do you prevent the formatrion of the ring of cells by growing Sf9 cells in Fernbach flasks?

Best wishes,

Geraldo.

[bob1]

The formation of the ring is not due to the flask, but rather is a property of liquid/solid interfaces, where you get high surface tension of the liquid that results in objects being pulled towards the high tension.  I doubt you can avoid it all other than by using roller bottles, and even these will have some cells being affected by a similar effect in some places in the bottle.

[Geraldo Oliveira]

Hi,

What you say sounds right.

However, don't you think that a flask made with a material with low tendency to adhesion (such as polycarbonate or, for the sake of argument, teflon) would prevent the formation of the ring of cells?

Best wishes,

Geraldo.

[bob1]

Potentially yes.  However, in the overall scheme of things a few dead cells are not going to make a real difference to your experiments - they should be roughly the same in both controls and treatments.