The coating was done last week at RIT (it was postponed from two weeks ago because of the failure of the e-beam crystal sensor). I deposited 10nm Ti and 15nm Au, without vacuum breaking. All the samples are from wafer…
Author: Jim
Professor McGrath holds a BS degree in Mechanical Engineering from Arizona State and a MS degree in Mechanical Engineering from MIT. He earned a PhD in Biological Engineering from Harvard/MIT's Division of Health Sciences and Technology. He then trained as a Distinguished Post-doctoral Fellow in the Department of Biomedical Engineering at the Johns Hopkins University. Professor McGrath has been on the Biomedical Engineering faculty at the University of Rochester since 2001 where he also served as the director of the graduate program in BME for more than a decade and currently serves as Associate Director of the URNano microfab and metrology core. Professor McGrath also has faculty affiliations with many other programs at UR including the Material Research Program, the Environmental Health and Sciences Center, the Biochemistry and Biophysics program, and the Musculoskeletal Research Center. McGrath's graduate, post-doctoral, and early faculty research was focused on quantitative experiments and mathematical modeling of cell migration covering molecular, cellular, and multi-cellular phenomena. This was true until 2007 when he, along with Professor Philippe Fauchet (now Dean at Vanderbilt) and PhD students Tom Gaborski (RIT) and Chris Streimer (Adarza), discovered a means to self-assembled nanopores in 15 nm thick free-standing silicon and demonstrated the remarkable transport properties of the new material in a Nature paper. This seminal discovery led to the creation of the multidisciplinary Nanomembrane Research Group (NRG) and the founding of SiMPore Inc. in the same year. The NRG and SiMPore have been dedicated to the advancement of ultrathin membrane technologies and exploring all of their potential applications ever since.
This blog also dates back to 2007 and has had contributions from more than 100 students, faculty, scientists, engineers, and entrepreneurs. It contains over 2,500 pages and posts logging progress large and small over all these years. Yet somehow it feels like we are just getting started.
TEM images of Actin on W303
A droplet (3uL) of 0.117 uM actin solution was added on membrane W303(0,2). Let the membrane sit in humidity Chamber for 20 min. Remove excess liquid. Add equal volume of Uranyl Acetate on membrane. Wait 90 sec. Remove excess liquid.…
Posted in NRG
I-V characteristics of coated membranes
I measured the I-V characteristics of our coated membranes on Wed. at RIT. JP observed the measurement. The semicon parameter analyzer in the test lab is “old” but isexactly what we need! Roughly speaking, our coated membraneshave resistance about 2k…
Posted in NRG
Pieces of Tong
The ‘Tong equation’ for liquid flow through a nanosieve is I refer you to the original paper for variable definitions (see page 285). For the flows that we see, this will always simplify to the much simpler equation … We…
Posted in NRG
Tong Predictions for w310
This is re-do of a post I made before the new year regarding the predictions of the ‘Tong equation’ for wafer 310 (I deleted the earlier post because I came to the wrong conclusion). I wrote MATLAB files to calculate…
Posted in NRG
Updated Hydraulic Permeability Plot
Here is a look at all our water permeability through nanomembranes to-date. There appears to be subtle trends showing increasing permeability with radial position (r – values) and a not-so-subtle trend showing decreasing flow with protein (cyt and albumin). Note…
Posted in NRG
Equation Governing Volume Transfers in the EQ format
I derived the governing equation for the volume transfer from SepCon devices in the wet/wet (EQ) format. It is … where the equilibrium volume for the cup can be calculated apriori using the cross sectional areas of the cup and…
Posted in NRG
Blowing bubbles from a nanopore
The following contribution comes from Jan Hoh – a Professor of Physiology at Hopkins, an invited speaker to BME in December, and a potential future collaborator. Jan sent his thoughts on why it is impossible to get flow through our…
Posted in NRG
Latest Water Permeability Figure for PES Membranes
Here is a slightly enhanced version of Mike’s latest hydraulic permeability data for commercial devices with PES membranes. The data at 22 and/or 34 PSI are a bit strange. Still the long-term trend seems downward. Similar data for PNC-Si membranes…
Posted in NRG
