Jim and I were wondering if we could “image” the membrane windows with the Tecan. A nice thing about the Tecan is that you can specify the number of measurements per well. For example, in this study, I acquired a 10×10 matrix of fluorescence intensities in a “filled circle” pattern (see below). You can also…
The pump’s data sheet (located here) describes the pumps materials as: polyphenylene sulphone (PPSU) polyimide (PI) nitrile butadiene rubber (NBR) It also says that the acceptable particle tolerance is < 50 μm. This is the info we will need to determine the types of particles we can use with an in-line flow system.
I repeated Barrett’s discoloration array experiment (Array1, Array2). NaCl solution was prepared @ concentrations: 0, 0.25 (0.1), 0.5 and 1M, whereas NaHCO3 solution was prepared @ 0, 0.475, 0.95, 1.90 (and 3.80) mg/ml. Different combinations of both these salt solutions were used and discoloration of non treated samples in oven@ 37C was monitored over different…
This post explains that electroosmosis in our material is higher than we expected. Jim suggested that maybe we don’t have fully developed flow in our thin material. Here I attempt to find the entrance length, or distance until fully developed flow, in our material. One needs to keep in mind that this is a continuum…
I recently completed a HUVEC adhesion study with commercial PET and pnc-Si transwells. HUVEC were seeded @ 100000 cells/cm^2, allowed to attach for 5 hours (upside down format) and then stained with CMFDA. Images were acquired without autocontrast, but I did autocontrast them in ImageJ to make them brighter. Corning Costar PET transwell: pnc-Si transwell…
Hi all, After a brief hiatus from winter break and my paper writing Mike and i have resumed our work on fabricating the counetrflow system, and we do have a success. Fabrication: The counterflow system is constructed based on oxide-layer protected pnc-Si, hosted within the V-notched Si-wafer that Dave specially produced for us. The membrane…
In an attempt to push the cutoff higher, we annealed two wafers outside the susceptor at 1000 C (SC 066) and 1100 C (SC 067) with a ramp rate of 100 C/s. The 1100 C does give a cutoff slightly higher ~5 nm, but I’m not sure if this is within the variability in different…
Below are a series of TEM micrographs showing a set of membranes produced last week. We RTPed these wafers at 700 (SC 062), 800 (SC 064) and 850 C (SC065) without the susceptor at a ramp rate of 100 C/s. The trend is increased pore size and porosity with increasing temperature which follows our intuition…
This is kind of a shot in the dark, but I wanted to see if I could get a zeta potential for pnc-Si that was as high as predicted by the electroosmosis results. First I tried to get the membranes to break in 1mL of PBS so that the windows were floating on top of…
As I told at the meeting, I tried spincoating PDMS on the membrane and it worked without breaking membrane. To make an ultrathin polymer film by spincoating the polymer has to be diluted in the particular solvent first. I used PDMS with elastomer to curing agent ratio (10:1) diluted in hexane (and xylene) by weight…