In my previous post, I mentioned the effects of varying electrode geometry on the TEER value measured from COMSOL simulations. I had assumed that membrane has uniform porosity i.e. 100% active area, which is the case with the commercial polymer…
Category: NRG
Anodic Bonding Setup at U of R
Previous Posts Anodic Bonding Theory, Anodic Bonding at RIT I’ve put together an anodic bonder setup here at the U of R and will be moving it inside the cleanroom shortly. I tried a couple of known combinations to…
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MgF2 Burst Pressure Analysis
Key Ideas I took a wafer with ~400 chips of varying square window sizes, ran my MgF2 process, and recorded the pressures it took to burst them. Overall yield was about 20%, most of them smaller windows. I was expecting…
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Variation of TEER as a function of membrane area (COMSOL simulations)
Background: This is a follow up to the blog that Jim wrote on the basics of TEER measurement. This is the link to my old blog, which also describes the theory and some other preliminary data about TEER measurements. The resistance (R) of…
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Why TEER Values are Multiplied by Membrane Area (DC Version)
Transendothelial electrical resistance measurements are expressed in the units . Where the measured resistance is multiplied by the area of the membrane to enable a comparison between measurements in different systems. We have often wondered why, but the reasoning for…
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NPN as an integrated filter for a NP Sensor
Last fall we decided to try to integrate a filter immediately upstream of Vincent Tabard-Cossa’s nanopore DNA sensors. The idea is to assemble back-to-back a NPN membrane a standard nitride membrane used in Vincent’s nanopore fabrication system an oxide spacer.…
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Integrated Electroosmotic Nanopumps on a Chip
As part of my thesis work, I hope to create modular pumps and flow sensors using silicon nanomembrane technology. Devices that could generate/detect microliter and nanoliter scale flows would decrease the overall size of microsystems, replacing larger micropumps (pneumatic PDMS, Chip-sized…
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Adding a Compressible Cake Layer to the Theoretical Model
In a previous post (linked here), I discussed a naïve way to incorporate concentration polarization into our theoretical model of the sieving of charged nanoparticles. Essentially, I considered the particles to be uncharged point particles that were subject to a…
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Surface Modification for Hemodialysis
We are continuing to work with the Shestopalov lab on surface modifiation of hemodialysis filters to prevent adhesion and activation. Jim recently presented our status and strategy (PDF) to the Technical Development Fund and was awarded the balance of the award,…
Error made when assuming identitcal pore size during simple flow modeling
Hi all, Sometimes for flow modeling I assume all pores to be identical in size. However, since larger pores allow much higher passage of flow, the above assumption will generally underestimate the prediction of flow. Presented here is a…
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