Given the mixed results of discoloration of RTPed samples from W613, which include no discoloration until 7 days (when the experiment was started within 2 hours of RTPing), and discoloration within 2 days (experiment started 8 days after RTP) I…
Author: Karl Reisig
Desalting BSA: Blank pnc-Si and Mini-Dialysis Units
The ultimate experimental goal of the desalting project is the removal of salts from a salt/protein solution while fractionating certain sized proteins with maximum protein retention and recovery.Thus far we have characterized the flux of salt through our membranes which…
BP Does Not Change with Membrane Orientation in Test Apparatus for W660
Given the low burst pressures of recently produced wafers Chris requested I burst pressure test some samples in two different orientations: well side facing away from the positive pressure source and well side facing towards the pressure source. The standard…
Bradford Assay to Quantify Protein Retention During Desalting
The ultimate experimental goal of the desalting project is the removal of salts from a salt/protein solution while fractionating certain sized proteins with maximum protein retention and recovery.Thus far we have characterized the flux of salt through our membranes which…
W648: Burst Pressure and the Return of Contamination?
We received W648 from the production team this week. Upon inspection of this wafer, is has a higher density of pinholes than we have been seeing lately (>3 pinholes/slit compared to 0 or 1/slit) and seems to show a return…
Karl's Air Permeability and Burst Pressure Raw Data
In this week’s meeting there was a request to have Maryna and I make our BP and AP data available online. While Maryna is at the Gordon Conference I thought I would upload what I have. The attached spreadsheet contains…
W613: Retest of Stability in Cell Culture Media
I recently repeated a chemical stability test of RTPed (5 min in Ar at 800C) samples from W613, which has the 30 nm pnc-Si layer. In this study I used DMEM +10% FBS as the culture media without cells. Previously…
Pore Processing Comparison of W615
In order to support the idea that RTP treatment does not change membrane pore characteristics (as shown by Anant in the rhodamine diffusion study) I processed TEM samples that were not treated, RTPed in Ar, for 5 minutes at 800C,…
Update of W637
Dave delivered W637, a wafer made using the sample recipe as W504, to us today. This wafer has a high occurrence of single pinholes, with only 12 samples pinhole-free. I also noticed some odd features on the membranes, shown below.…
Silanization and Membrane Chemical Stability
Due to our desire to improve membrane stability in cell culture, different methods of treatment have been mentioned to try, including carbonization and silanization. W606 was treated with UV/ozone at 150C for 20 minutes, followed by silanization performed by some…
