Tuesday November 15 4 PM
Speaker: Dr. Holly A. Stretz (Tennessee Technological University)
Title: Nanoparticle Patterning in Hydrogels and Other Nanomagic
The use of hydrogels and electrophoresis for bio-separations is a relatively mature technology, useful because it is inexpensive to operate and has an established infrastructure within the field of medical diagnostic laboratories. There are a number of difficulties associated with use of this technology in separations of proteins however, including poor handling characteristics of the gel, poor shelf life, and the likelihood of poor separation given the complexity of many biological samples. The technology simply does not offer much in the way of tunability, responsiveness, or in-situ customization to accommodate the realities of protein separations.
Typical hydrogels used for protein separations consist of a polymer, in many cases polyacrylamide, formed into “cells” in water with no reinforcement. Nanocomposite hydrogels formed with a Montmorillonite (MMT) dispersed phase are well known to increase the strength of hydrogels, as reported extensively by Haraguchi et a. The question is can these novel materials then produce unique interactions with proteins ? Computational techniques have shown that nanochannels in particular can produce unique environments for protein separation. A composite hydrogel with a well-dispersed anistropic nanofiller can produce nanochannel-type morphology, although the composite hydrogel is an example of a sequenced array of nanochannels as opposed to a single nanochannel. Furthermore, with careful formulation the nano-morphology of the hydrogel has potential for being morphologically responsive or tunable. We present early work demonstrating formation and characterization and novel protein separations for this new class of hydrogels. We will also discuss useful transport models which match experimental protein mobility studies for certain electrophoretic flow regime. Further, the implications are that tunable morphologies/hierarchal nanoparticle patterning can impact diverse applications such as organophotovoltaics and current sensors.