Over the past few days Josh and I installed windows 7, windows office suite, Malvern’s Zetasizer software (available online), Tecan’s I-control software (available in the 3-ring binder in the glass cabinet above the machines), and chrome onto the new(er) laptop…
Author: Karl Smith
Karl is the 'separations czar' for NRG. As a Biophysics Ph.D. Candidate, Karl has the responsibility of characterizing new membranes, modeling the unique physics of nanomembrane separations, and finding ways to apply pnc-Si technology to protein purification, nanofluidic transistors, and human hemodialysis. Karl graduated from Allegheny College in 2011 with a double major in English and Physics.
E-beam Deposition of Ag, Cold ALD Runs, and Sepcon Assembly For Making a Nanofluidic Transistor
Last week I conducted a variety of experiments to try to make a nanofluidic transistor (a device described in detail in this previous journal club post). I did some light optimization of the E-beam deposition of Ag films over a 3nm…
Posted in NRG Tagged with: 100C ALD, 5 nm gold, Ag film, Dynamically Modulate Surface Charge, Nanofluidic transistor
Mr. Smith goes to Boise
On June 10th, 11th, and 12th I was in Boise, ID for the North American Membrane Society (NAMS) annual meeting. While there, I presented Jess’s work on the EO pump in a poster session. I got the chance to meet Andrew…
Posted in NRG
Using Alumina Deposition to Modulate Pore Size
The Cambridge Microsystems Savannah 200 atomic layer deposition (ALD) system uses a two-step chemical process that alternates pulses of water vapor and trimethylaluminum (TMA) to build a layer of Al2O3 on a silicon substate. Because of the two-step nature of…
Control of DNA Capture by Nanofluidic Transistors
This lovely paper: 121025 – ACSnano fluidic transistor pore details the creation of a “nanofluidic transistor”. In essence, by changing the charge on the (metallized) membrane from 0V to 500V, the group can completely stop the transport of DNA molecules (which are…
Posted in NRG
A nifty little Matlab code to show why we need to wet the backsides of the membranes
I couldn’t really make sense of what was happening in this post, and in particular this figure threw me for a loop: So to help myself understand the relationship I whipped up a little matlab app to show the…
Posted in NRG
INT results from 4/3/13
I brought some 20nm and 40nm Sepcons to Integrated NanoTechnologies last Wednesday. First, we passed some short radio-labeled DNA strands through a 40 nm Sepcon, and then some longer strands. Both were able to pass through the membrane with a…
Posted in NRG
Combining Pores Affects the PoreImageProcessor, but Not Enough to Throw Permeability Off 2x
In Tuesday’s NRG, we wondered if the fact that some of Josh’s pores overlap could throw the PoreImageProcessor off enough to explain a 2x discrepancy between our theoretical hydraulic permeability and our experimental permeability (the experimental was lower). From this picture: I took the…
Posted in NRG
Science Saturday – Volunteers Needed!
Hey folks, Science Saturday is this Saturday and Sunday at the Rochester Science Center. We need volunteers to man our tables from 12-4pm on both Saturday and Sunday. Please indicate in the comments of this post if you can volunteer,…
Posted in NRG
Make Sure to Filter Salts Before Passing Them Through Sepcons
Previously, I had gotten some inexplicable results showing that increasing salt concentration decreases the flow through a membrane. This makes no sense (and goes against our previous data) because we would expect electrostatic forces to counteract the flow, an effect…
Posted in NRG
