Biomedical Engineering and Bioengineering Commons^™

The Use Of Microfluidics And Dielectrophoresis For Separation, Concentration, And Identification Of Bacteria, Cynthia Hanson, Michael Sieverts, Karen Tew, Annelise Dykes, Michaela Salisbury, Elizabeth Vargis

Biological Engineering Faculty Publications

Traditional bacterial identification methods take one to two days to complete, relying on large bacteria colonies for visual identification. In order to decrease this analysis time in a cost-effective manner, a method to sort and concentrate bacteria based on the bacteria's characteristics itself is needed. One example of such a method is dielectrophoresis, which has been used by researchers to separate bacteria from sample debris and sort bacteria according to species. This work presents variations in which dielectrophoresis can be performed and their associated drawbacks and benefits specifically to bacterial identification. In addition, a potential microfluidic design will be discussed.

Rational Design Of Rama-Labeled Nanoparticles For A Dual-Modaility, Light Scattering Immunoassay On A Polystyrene Seubstrate, Nathan D. Israelsen, Donald Wooley, Cynthia Hanson, Elizabeth Vargis

Biological Engineering Faculty Publications

Background: Surface-enhanced Raman scattering (SERS) is a powerful light scattering technique that can be used for sensitive immunoassay development and cell labeling. A major obstacle to using SERS is the complexity of fabricating SERS probes since they require nanoscale characterization and optical uniformity. The light scattering response of SERS probes may also be modulated by the substrate used for SERS analysis. A typical SERS substrate such as quartz can be expensive. Polystyrene is a cheaper substrate option but can decrease the SERS response due to interfering Raman emission peaks and high background fluorescence. The goal of this research is to …

Microbubble Assisted Polyhydroxybutyrate Production In Escherichia Coli, Kadriye Innan, Fulya Ay Sal, Asif Rahman, Ryan J. Putman, Foster A. Agblevor, Charles D. Miller

Biological Engineering Faculty Publications

Background

One of the potential limitations of large scale aerobic Escherichia coli fermentation is the need for increased dissolved oxygen for culture growth and bioproduct generation. As culture density increases the poor solubility of oxygen in water becomes one of the limiting factors for cell growth and product formation. A potential solution is to use a microbubble dispersion (MBD) generating device to reduce the diameter and increase the surface area of sparged bubbles in the fermentor. In this study, a recombinantE. coli strain was used to produce polyhydroxybutyrate (PHB) under conventional and MBD aerobic fermentation conditions.

Results

In conventional …