We are using PORTEX polyethylene tubing (ID 0.38 mm, REF 800/100/120) with cells (from cell culture) and we have realized that the cells seem to not flow through it when using low flow rates (lower than 20-30 ul/min), as if they were somehow adhering to the walls. They flow better when using higher flow rates, but there are still fewer cells than in the original sample after they flow through the tubing. Has anyone experienced something like this? Which alternative tubing would you recommend?
I agree - I don't think your worry is necessarily a material issue. Any time a mammalian cell sees a surface it is likely to want to stick to it, particularly harder surfaces. You see the lower amount of cell sticking in the higher flow rate because you are (1) giving more momentum to the cell solution and (2) they will shear (aka less likely to stick).
However, cells are pretty heavy, and this definitely shows in the lower Reynold's number flow regimes you subject cells to in a microfluidic chip.
You can consider coating your tube with a biocompatible surfactant when you flow them through, such as Plutonic F-68. That may help shear them off a bit easier before they settle and release their adhesion proteins to the tube surface.
I know about sedimenting issues, but my pump can also work vertically and we have tried this already. Also, I am working with a non-adherent cell line, so it does sediment even less. With adherent cell lines this problem becomes more obvious, so it might be related with the cells sticking to the tubing. I want to know as well if people have the same issues when using this tubing or if it is a general issue when using other tubings as well like the classic Tygon.
- Badges
- Science topic