Counterflow Dialysis

A quick update since we last talked about how DNA controls were proving to be problematic: Things are working again (more or less). I went back top basics, remade most of my solution, ordered new DNA samples, and, most importantly, piranha-cleaned my chips. The first three experiments I did on basic 30-nm thick 5.4mm square…

Our friends at McGill university have wanted to incorporate our chips directly into their platform for squeezing and confining DNA. Their desires come in a form of a device where we can seal the SiMPore chips into glass channels without any intermediate gasket layers. In the video above, we can see the relevant layers, a…

Submitted on April 7, 2014. Posted to NRG Cloud under NRG/Funding. Figure 2. Dead End Filtration with SEPCONTM (A) SiMPore’s SEPCONTM  spin cup with a silicon nanomembrane chip. B) Dead end filtration in a centrifuge. The direction of the centrifugal force is indicated with the gravity vector g. Figure 3. Nanoporous Silicon Nitride (A) pnc-Si…

Here is an attempt at the active area figure using the “newer” EO membranes (SC172).  Here is the raw flow data for the three membrane sizes: If we take the slopes from this figure, we get the flow rates in uL/min.  We can then plot against active area: We get a pretty nice fit here,…

In my last post I showed that using buffered solutions instead of Di-water we could obtained similar results with SC256 as we had with SC269. I used 20mM HEPES at pH7.5 with no salts and showed DDM diffusion through both “treated” and “untreated” SC256 samples. Additionally I showed that “treated” SC256 samples appeared to slow…