Our recent work using NPN to separate free IgG from 20 nm NPs has shown that we can pass liquid under either forward or reverse configurations using the centrifuge.  We had thought that there would be greater resistance in the…

I’ve been taking lots of zetapotential measurements with my current setup. Serendipitously, it appears that the more I use the electrodes, the more stable my zetapotential measurements become. Because the system seems well behaved now, I decided to move on to…

In my last post, I described a new process for reducing fluoropolymer build up during RIE. Unfortunately, the new process had substantially lower yields (half) than the process I was using before. In this post, I am detailing my attempts to…

In our previous post I relate how our first experience with the membranes encountered some difficulties.  These were mostly of two kinds:  clogging or braking of the membrane and somewhat arbitrary sizing of the particles.  We think we have fixed…

Josh has just started teaching us how to play with these; some early findings: – So far, standard centrifugation results mostly on the caking of lipids that clogs the membranes. – Use of the pressure cell has shown some promise,…

As discussed in a previous post, we decided to test chips from wafer #1070 because they have smaller pores than those used in the most recent forward vs. reverse study. In the forward direction, 31 uL of filtrate was passed…

We still have plenty of things to do, but after five weeks working at the UR, we have come a long way: – Chip production for instructional use:  done – Design and production of SU8 mold: done – Protocols for (@Fisher)…

Last week Sarah and I made several standard nanofluidic transistor (NFT) stacks (3 nm Ti, 12 nm Ag over a 3-slot SiN membrane – wafer # 1024) in the cleanroom. I then measured the zetapotential of these devices at pH 7.43,…

I have a preliminary result from Kevin that there is a layer of fluoropolymer remaining on my MgF2 freestanding nanomembranes (which could explain some of the carbon signal in EDX from my previous posts). This would create another unnecessary signal…

This is the method Brian McIntyre developed for the recent URNano Microfluidics Workshop. Based on a polyaddition-based mechanism based on introducing amine groups onto the surface of one material and epoxy groups on another material and enabling the amine–epoxide polyaddition reaction…