Comparison of Treated and Untreated Diffusion
In preparation for Tuesdays meeting Jim asked me to prepare this chart to compare the results of the treated and untreated diffusion experiments from this summer. The chart values given are the percent concentration of the sample filtrate in comparison to the original “feed” solution. For instance in all of my experiments the initial “feed” solution was 6uL and the backside volume was 60uL, therefore if the system were to reach equilibrium then the concentration of the backside volume would be 10% of the initial “feed” solution.
The chart is broken into two main sections: (1) DDM and (2) BSA. Each of these sections has three subsections to include all the experimental conditions run this summer; (1) DI-water, (2) buffer, and (3) salts. Finally each section includes the untreated (U) and treated (T) data.
From the chart we can see that the T/U ratios for the majority of the DDM experiments are approximately 1. This makes sense if we expect the diffusion of uncharged detergent molecules to be limitedly effected by buffer and salts. What this shows is that for all the conditions tested this summer relatively equivalent amount of DDM diffused across the membranes for both the treated and untreated case. On the other hand the results for the T/U ratios for the BSA do not seem to be centered around one indicating that there is a dependence on treatment for BSA diffusion.
Looking at the BSA results for DI-water it appears that based on these calculations the treated samples are allowing a greater “concentration” of BSA across than the untreated samples (T/U values greater then 1) . I am not sure what this means exactly and I was hoping that we could talk through it during meeting on Tuesday. If you do compare the untreated and treated %-feed concentrations for a single wafer trial it does appear that the DDM concentrations are higher then those for the BSA. Obviously a more indepth statistical analysis is going to be needed but I thought it best to talk through the numbers first.