Cells on 6-slit pnc-Si transwells
With the previous 2 experiments, I made a couple of 6-slit pnc-Si transwells. These chips were from the cell culture wafers I had made a while ago. These samples (SC126) were RTP’ed before use.
My improved technique, combined with the RTP, enabled me to keep cells growing on these pnc-Si samples for 1 week WITHOUT the membranes breaking. In fact, only 1 of the 10 pnc-Si transwells I made for this experiment broke during the week of cell culture. This is a significant improvement of my experience from earlier this summer/spring.
These are bEnd3 cells, P8, seeded at 100000 cells/cm2, grown past confluence and then imaged with Live/Dead 7 days post-confluence. To try to get the most information, I only took 4X images.
Looks pretty good – a monolayer of cells. However, you can distinguish the membranes by the brighter cell staining over the slits. This is due to the clumping/rounding phenomenon I discussed in the last post. The other 2 slits are off the bottom of this image – I couldn’t fit all 6 in the 4X window.
Here’s an overlay with dead cells stained red.
YIKES.
There does seem to be an edge effect with pnc-Si transwells, similar to commercial PET transwells. Is this from something leaching out of the Sepcon/O-ring – I don’t know. It could be due to relatively less nutrient/waste transport due to the wall of the Sepcon next to these cells. I guess the edge effects would become a problem for us if we start making samples with membranes toward the edge of the silicon chip. There is a concentration of dead cells over the membranes, as noted in the last post.
Can you grow the cells with a chunk of o-ring or a piece of plastic to see if those materials cause the die off?
Yeah, I can do that pretty easily – I just need to set it up.
I have observed before that cells do not adhere/grow in presence of o-ring. I had tried using the o-ring (before cloning ring came to rescue) to prevent rolling of cells from the chip surface in 2D format.