Previous Post We discussed in meeting having Maryna also calculating the permeabilities for this figure. Here is a figure with the experimental, theoretical permeabilities from Dave’s, Maryna’s, and my processing, and an average of the three theoretical permeabilities. I then took this average and made the following figure. I did omit w312, as the super…
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…
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…
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. …
The Bernhard group wants to use our membranes to separate pieces of DNA. During their experiments they noticed that some of their samples caused discoloration over the summer. Since then, I’ve been helping a new student to the project, Paul Black. He first started by testing pH, and found that higher pH leads to fast…
I attempted a diffusion study with w685 three days ago. If you were following the comments on the w685 page, you’ll know I had some difficulty pipetting the protein solution into the well. I haven’t had this problem recently, and when I used to encounter this problem I would etch the remaining backside oxide with…
I guess there was a mistake in the last permeability plot. The real data for the 4 bar plot should look like this: Unfortunately that doesn’t look so good anymore. The third bar though is the one that I originally processed to have many more pores (w705). The reprocessing gets it down in the 8%…
In my previous post, there still appears to be a discrepency between the calculated pore statistcis and the experimental permeabilities. I explored what I could do with the pore processing to bring the experimental closer to the calculated permeabilities. I set the minimum pore cutoff higher (15nm) and tried to remove any pores that did…