My previous discoloration post showed that chips in the Sepcon format discolored much slower than flat chips. A flat chip in the same well as a Sepcon chip seemed to accelerate discoloration. One thing about the Sepcon format that I hadn’t thought of earlier was that pnc-Si in Sepcons is autoclaved for sterility. So I…
Previous Post on Water Permeability Figure We decided at the last meeting to show water permeability for each membrane used rather than plot for a specific characteristic like porosity. I did this but there were a few samples that still had a noticeable deviation between experimental and calculated permeabilities. I asked Dave to reprocess the…
Cellulose Membranes I set up a 24 hour diffusion experiment with Millipore 30kD cellulose membranes as shown in this picture: After 24 hours I collected retentate and filtrate and visualized on the following gel: I didn’t expect to see a separation so similar to our pnc-Si results in this format considering the extremely poor dialysis…
I’ve been doing some preliminary studies with HUVEC in commercial transwells and on pnc-Si in the Sepcon/transwell hybrid format. The thinness of pnc-Si will enable better microscopic examination of cells than other membrane systems (if pnc-Si is flat). I thought it would be interesting to compare commercial transwells to the pnc-Si “hybrid transwell” format in 24-well plates via…
I ordered some new AC160 tips last week from Asylum and got on the AFM Thursday to test them out. I think they solved some of the problems I was running into over the last few weeks. Mainly, I was finally able to image entirely in repulsive mode (which was impossible with the older tips). All of…
Back a long time ago, I had performed some separations with the aim of showing the usefulness of pnc-Si in hemodialysis. I attempted separations of albumin (an important protein to be kept in the blood) and cytochrome c (used in hemodialysis research to cheaply approximate the toxic protein b2microglobulin) using three different membranes. Here is…
Hi all, the technique of UV Ozone bonding (of PDMS to glass, Si or pnc-Si) is now complete, serendipitously. Hsin from Miller lab want to bond PDMS to glass, they tried plasma oxidation treatment and it worked. The method is as followed: plasma oxidation treatment for 35 sec (which did not bond the sample, when…
Here is the figure we talked about in the last meeting. For each specific membrane, I’ve plotted both the experimental permeability and the permeability calculated from the theory. You can see in some cases they are close, but in others they can be pretty far off. Omitted from this chart are retests. Updated: Graph is…
Follow-up to Pressurized Movable Cutoffs. Wafers 670 and 673 were not holding up in PBS for the 24 hour diffusion experiment duration. RTP treatment at 800C for 60s enabled chips from both of these wafers to last 24 hours. Here are the results from the gels: We definitely have two different cutoffs in these experiments. …
I performed a discoloration experiment with w639 in EGM + 10% FBS. I put 2 blank chips in the Sepcons membrane side down. I then placed one Sepcon in a well with EGM alone. The other Sepcon was placed in a well with EGM but also with another chip (labelled as Sepcon with chip, chip…