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.

Table of Gas Permeance and Water Permeabilities for Various Nanomembranes

Wright, E., Miller, J.J, Csorda, M.. Gosselin, A.R., Carter, J.A., McGrath, J.L., Latulippe, D.R., Roussie, J.A. (2020) Development of Isoporous Microslit Silicon Nitride Membranes for Sterile Filtration Applications Biotechnology & Bioengineering https://doi.org/10.1002/bit.27240 DesOrmeaux, J. P., Winans, J. D., Wayson, S.

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Large Pores Dominate Flow Through Nanomembranes (FOW)

Because of the non-linear dependence of volumetric flow rate on pore size … where t is the membrane thickness and r is the pore radius, large pores contribute disproportionately to the total flow through a membrane than small pores. The

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NPN Clogging with Particle Size and Concentration (FOW)

This figure appears in our 2016 JMS paper and describes the clogging behavior of NPN with a 37 nm average pore size. The y-axis is the volume of filtrate after 1 min of forward centrifugation at 690g (3000 RPM). The

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The Rate of Protein Binding to Surfaces

When we coat surfaces or particles with proteins we often wonder, ‘how long until the coating is done? ‘ In this 2009 paper we addressed the question directly. We soaked 100 nm polystyrene particles in 10% serum (about 6 mg/ml

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Nanoparticle Concentrations

Knowledge of the particle number is critical in many of our applications. In trying to rationalize membrane ‘clogging’ by particles for example, it is wise to compare the particle density to pore density at the membrane. When conjugating protein to

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Darcy’s Permeability

Darcy’s Law relates the volumetric flow rate Q through a porous media in response to a pressure gradient $latex \Delta P $. … $latex Q = \frac{\kappa A}{\mu}\frac{\Delta P}{L} $ Where $latex \kappa $ is the intrinsic permeability of the

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