Abstract

The Benefits of Being Thin: How Ultrathin Silicon Membranes are Enabling New Technologies for Discovery in Biomedical Research

James L McGrath, , University Of Rochester

A decade-and-a-half after we first used silicon microfabrication to create free-standing ultrathin nanoporous membranes, the materials are being utilized by a growing number of laboratories as uniquely capable tools for biomedical research. Today we manufacture a variety of silicon-based nanoporous and microporous membranes with the common characteristics that they are ultrathin (15 nm - 300 nm) with well-defined pore sizes. The extremes thinness of 'nanomembranes' makes them orders-of-magnitude more permeable to both diffusing molecules and pressurized flow than conventional membranes. The ultrathin nature of the membranes also gives them a glass-like imaging quality in optical microscopy. These properties provide abundant opportunities for novel membrane-based devices and assays. This talk will provide an overview of two leading applications of our nanomembranes. First is their use to create in vitro models of human tissue (i.e. 'tissue chips' or 'microphysiological systems' where they provide optically transparent and highly permeable scaffolds to compartmentalize tissues including the brain neurovascular unit, the blood-retinal-barrier, bone, and tendon. The second application I will cover is the use of as tool for diagnostic applications. Here we have leveraged our understanding of filtration to develop a digital assay of extracellular vesicle biomarkers and pressure-based sensor that detects virus in a point-of-care microdevice.