A while back, we discussed leaving the rotation stage off during the a-Si deposition to induce a thickness gradient over a single wafer.  The purpose of this experiment was to explore the different morphologies vs. thickness at a given RTP treatment.  We estimated that we could cover a 3x thickness range over a 8 cm…

In my last diffusion experiment, I used wafer SC 442. The results seemed to show that IgG was indeed diffusing through the membrane. As a follow up experiment, I am trying to show that I can pass IgG through more than just the one membrane. Furthermore, SC 505 has a much larger average pore size…

As I was preparing for the BMES conference, I took a few pictures of endothelial cells on pnc-Si transwells that showed extensive vacuole/endosome expression (here).  The most dramatic example occurred on a 50nm-thick membrane that was barely porous.  So I wondered – are cells responding to mechanical or porosity differences (or both, or something else)?…

The results of my last diffusion experiment regarding BSA and filtered IgG (using SC 364) were inconclusive. (See “Diffusion Test– filtered IgG and BSA”) Looking at the histogram of results, there is no clear difference between the absorption of filtered IgG and buffer A. For this follow up experiment, I used SC 442. Of the…

In my 1st post detailing glial cells on pnc-Si transwells, I saw lots of cell clumps above the membrane window (see here).  Since these cells were grown in the wells, I thought they could be piling on top of each other in the wells and getting trapped.  Here, I decided to flip the sample so…

Permeability was calculated with Dagan theory for membranes in this post.  Pore processing was performed and r.mat files were run through the programs used to calculated permeability in submitted Science paper. No Carbonization Experimental: 591 ul/(min*PSI*cm^2) Theoretical: 801 ul/(min*PSI*cm^2) Carbonized (6.2 nm taken out of diameters) Experimental: 289 ul/(min*PSI*cm^2) Theoretical: 438 ul/(min*PSI*cm^2) It seems that there…

A simple hydraulic permeability study was performed to determine whether carbonization would negatively impact water transport through the membranes. 5 slit square SepCons from SC 471 were carbonized and put in the ultra-centrifuge with a 500 uL starting volume.  The samples were spun for 10 minutes at 3000 RPM (equiv to 4.95 PSI starting). SC…

SiMPore has been collaborating with the Infotonics Center to scale our SepCon production to a 6-inch wafer.  The wafers are patterned and deposited at their facility and then brought back to UR where we anneal and etch.  This week, we etched several wafers and the initial results look promising.  The big news is that we…

I’ve suspected that the barrier function of endothelial cells might be surface-dependent (that is, cells grown on the pnc-Si side vs. cells grown on the well side).  I hypothesized that the interface between membrane and well walls would alter the continuity of the endothelial monolayer when cells are grown on the well wide.  To test…