As I mentioned in the meeting this morning the SC267 samples have run out so I have begun testing SC269 for use in my experiments. This post pertains to a BSA diffusion experiment that I set up yesterday and allowed to run overnight. I took two SC269 samples; “treated” the first for 20min at 150C…
Building on my recent posts I ran an experiment with SC267 testing the ability of BSA and DDM to diffuse through UV-Ozone treated (20min at 150C) and untreated samples. I used four samples testing both BSA and DDM in the treated and untreated cases using Jess’ diffusion cell. Again 6uL was placed on the membranes…
In my last post I presented the results of an experiment in which it appeared that BSA did not diffuse through a SC267 sample treated in the UV-Ozone system for 20min at 150C. As a control I also ran BSA dissusion through an untreated SC267 sample and showed that BSA did move across the membrane….
As mentioned in my previous few posts Justin and I have been working to characterize contact angles resultant from various exposures in the UV-Ozone system. Earlier this week we got our new oxygen tank installed and it appears that after using the 15min cleaning protocol (15min@150C with vacuum) noticeable decreases in contact angles can be…
Last week I made a post showing the diffusion of DDM and BSA through SC267. I an effort to increase the negative charge associated with the membrane material I proposed using UV-Ozone exposure. A while back there was some concern that the UV-Ozone system was contaminated by PDMS, and that a standard cleaning protocol needed…
Last week I made a post showing detection of detergent diffusion across membrane SC267. In the diffusion set up I had placed 6uL of a 50/50 volume ratio solution of 1.0% DDM and 1mg/mL BSA with 60uL of DI-water on the membranes backside. I allowed the setup to sit for two days and then used…
In a previous post I showed that a colorimetric assay using sulfuric acid and phenol can be used to establish a linear relationship between known detergent concentrations and absorbance values. This assay proves helpful in the project related to Mark Dumont’s work in that it will allow detection of small quantities of detergents that pass…
After talking with Prahnesh, a graduate student in the Dumont Lab I obtained a protocol for a colorimetric assay used to detect the presence of detergents in solution. The assay uses phenol and concentrated sulfuric acid in the following manner: add 600uL Sulfuric Acid to 40uL of sample and vortex add 200uL 5% Phenol and…
I took a look back through the Melvern data I collected, particularly focusing on changes in the intensity data in the BSA-DDM solution (the previously posted plots were of number data). When I compared the peak intensities for BSA, DDM, and DDM-BSA complex I noticed that the intensity peaks fall over the same size distribution…
Yesterday I used the Melvern to determine particle size and zeta-potential for BSA in DI-water. For the particle sizing I used a concentration of 2mg/mL but I had to increase the concentration to 10mg/mL in order to get an accurate zeta-potential measurment. As shown above the size measurements provided an average diameter of approximately 5.6nm….