George Wadsworth Training Visit

Ultimately we want to use SiN-NP filters to separate viruses or some other biological species, but repeated attempts to pass 20 nm fluorospheres in water or PBS have failed.  Au particles, however, have passed through the filters.  This post reports the results of Sarah and I attempting to pass Au particles from 20 to 100…

We desire to test the electrical perfomance of our membranes in the iBidi chamber. For comparison, I am using a gold standard Ussing chamber format to examine the contribution of our membranes to the overall frequency response of a system. I am using both a matlab model and a web-simulator (www.circuitlab.com) to examine an equivalent circuit model…

For the charge model, we would like to know the surface charge density and size of our experimental molecules.  I’ve attempted to use the Zetasizer for both measurements, but as mentioned in my diffusion paper, DLS gives sizes that deviate from the expected or crystal sizes.  Since zeta potential measurements require large amounts of highly…

One of Christine’s projects was to determine if pinholes affected electrical resistance (TEER) measurements.  She summarized her work here.  I collected her data and did some negative controls to finish this work up.  Here’s the graph: The “no membranes” data is from Sepcon transwells with pnc-Si chips but without membranes (I broke them before assembling…

Silicon nanomembranes are ultrathin, free-standing structures that vary from 10 – 100 nm in thickness. These membranes are at least 1 order of magnitude thinner than the thinnest polymeric membranes. Pores can be manufactured on these membranes to have diameters ranging from 5 nm – 10 μm with porosities ranging from 2 – 20%, allowing…