Previously W514 was tested with different RTP conditions (varying time at 800C, all in Ar); the results were difficult to interpret as the cells were confluent (in some cases it was hard to see membrane breakage). We therefore decided to run a similar test again, with a slight change in O2 addition during RTP. O2…
Previously I ran a chemical stability study of samples from W613, which has a 30 nm thick pnc-Si layer. In that study complete failure of untreated samples was observed by 18 hours in cell culture, which was not a significant improvement from sample lifetime of 15nm thick pnc-Si. To see if RTP treatment helped the…
Four different post-production treatments with the objective of improving membrane stability in culture were run last week on W615, a pinholed wafer laden with the circular features we have been seeing recently. I ran four different conditions for cell culture: no treatment (n=3) UV/ozone for 5 minutes at room temperature (n=4) RTP in Ar for…
W613, the wafer with 30 nm thick pnc-Si was tested for chemical stability. This wafer was shown to be very weak mechanically, with burst pressures less than 1 PSI. I tested this wafer for chemical stability with cells (fibroblasts, P26) in DMEM +10% FBS (n=5). I also monitored discoloration in DMEM +10% FBS w/o cells…
W613, the wafer with 30 nm thick pnc-Si that is oddly etched to form “H” shaped membranes, was tested for burst pressure and attempted to measure air permeability. When doing air permeability all samples broke, meaning are very weak. This was demonstrated in the burst pressure values, shown below. I guess the large, oddly shaped…
The production crew recently delivered W620 to the lab, which was created to mimic W504 (and W612). W620 shows high burst pressure and has air permeability comparable to W504/612.
As mentioned previously intact membranes show a flux comparable to membranes with pinholes during desalting experiments. To confirm this a third intact membrane test and two pinholed tests were run under the exact same conditions. Previous pinholed samples had different NaCl solution volume in the SepCon, I wanted to remove any variability caused by this….
Yesterday I found a bug in the pore image processor. The “i” hotkey is supposed to save the current image, but it wasn’t working. I contacted Mike Bindschadler and he fixed it. The updated version can be found here. The only change is in the “pore_processing_gui_call” .m file. Happy processing!
I tried to clean samples from W615 using UV/ozone to cleanse the membranes of the organic impurities we have been seeing lately. I followed the UV/ozone protocol, with a stage temp of 25C and treatment time of 5 minutes. No change in the impurities were observed; I plan on trying to run it again for…
I tested W612 for air permeability and burst pressure, shown below. It should be noted that the air permeability and burst pressure values are comparable to W504; looks like a good reproduction! I also tested a sample with the hexane residue and debris, no difference in permeability or burst pressure was seen. Background pores included…