Senior Member of the Technical Staff
Biotechnology and Bioengineering Department
(925) 294-2692 / firstname.lastname@example.org
Microfluidics, point-of-care clinical diagnostics, radiation biodosimetry, protein separation science (electrophoresis, centrifugation, isoelectric focusing and fractionation, pore limit electrophoresis), hematology, biomarker detection, sample preparation.
My research interests involve developing lab-on-a-chip technology for clinical diagnostic applications. We focus on scenarios in which a deployable, point-of-care device is required or access to conventional assay equipment is limited. Examples include mass population exposure to toxic agents or ionizing radiation, diagnostics for warfighters in the field, screening of astronaut health in space, and border security. Our microfluidic tools enable rapid analysis of minute volumes of human samples, such as blood or saliva. We work alongside Sandia’s systems engineers to develop portable, fully-integrated, automated diagnostic devices.
Team Members: Ulrich Schaff, Bob McCoy, Ron Renzi, and Augusto Tentori
Collaborators: Dr. Natalia Ossetrova and Dr. William Blakely, Armed Forces Radiobiology Research Institute
Biodosimetry involves using biological signatures to assess the dose of ionizing radiation one has received following an exposure event. In a mass-exposure scenario, it is important to quickly identify those requiring treatment from the “worried well” as rapid therapeutic administration is crucial. Current biodosimetry techniques require sophisticated laboratory equipment available in a limited number of facilities, and can often require several days to a week for results. In collaboration with the Armed Forces Radiobiology Research Institute (AFRRI), we are developing a point-of-care device capable of detecting protein and hematological biomarkers indicative of radiation exposure. The device uses centrifugal “lab-on-a-CD” technology to achieve total sample-to-answer in <10 minutes from a pinprick of blood.
Team Member: Anson Hatch
We have developed a robust technique for generating on-chip polymer gradients, in particular, microscale immobilized pH gradients (µIPG’s) for rapid and high-resolution isoelectric focusing. Precise amphoteric monomer gradients are established via diffusion and are immobilized following photopolymerization, resulting in a well-defined pH gradient. We have achieved rapid (<20 minutes) and high-resolution (δpI ~0.040) focusing across 6-mm-long µIPGs.
Team Members: Junyu Mai and Anson Hatch
We are also exploring the use of discrete, pH-specific membranes photopatterned on-chip for conducting isoelectric fractionation of proteins. Proteins are distributed into “bins” based on their isoelectric point following electrophoretic transport across a series of individual membranes. Individual bins can then be accessed for further analysis. This technique lends itself to sample preparation, in which trace analytes can be isolated and enriched from high abundant species present in a complex sample. This modular approach can be easily integrated with other on-chip methods for automated processing and detection.
Team Member: Anson Hatch
To demonstrate another on-chip separation method, the same fabrication technique used to generate µIPGs was adapted to establish and polymerize polyacrylamide porosity gradients. This allows proteins to be fractionated based on their size by electrophoretically driving them toward their effective pore limit—the pore size at which migration is essentially halted. The method also lends itself to sample enrichment due to the stacking phenomenon achieved with decreasing analyte mobility. Concentration factors >40,000 were easily achieved.
Team Members: Anson Hatch and Ariel Hecht
Collaborators: Dr. Ross Durland and Dr. Xianbin Yang, AM Biotechnologies, LLC
In collaboration with AM Biotechnologies, we are configuring assays upon the RapiDx platform to screen astronauts for biomarkers indicative of spaceflight-related conditions, such as bone loss. The assays use thio-modified aptamers as affinity reagents. Aptamers provide several advantages over antibodies that are crucial for spaceflight applications, including stability, resilience to extreme ambient conditions, and low molecular weight that provides high resolution separation of small analytes. The compact RapiDx platform is well-suited for deployment in space where spatial footprint is of high importance.
Team Members: Chung-Yan Koh, Anson Hatch, and David Walsh
Collaborators: Dr. Easwaran Ravichandran and Dr. Bal Ram Singh, University of Massachusetts Dartmouth
Botulinum neurotoxin (BoNT) is the most toxic substance known, with a human lethal dose of ~1 ng/kg. The current gold-standard diagnostic is the mouse bioassay, a >4-day test in which laboratory mice are infected with sample and observed for signs of botulism. We are configuring the RapiDx portable medical-diagnostic device so that it can conduct electrophoretic immunoassays that will detect the presence of the toxin’s heavy and light chains. The toxin’s potency will also be quantified through a parallel enzymatic-activity assay. I am developing methods that will be used in the assay to isolate regions of sample incubation and SDS denaturation on-chip prior to separation.
|2006–2008||Ph.D., Mechanical engineering, University of Michigan, Ann Arbor, MI|
|2004–2005||M.S., Mechanical engineering, University of Michigan, Ann Arbor, MI|
|2000–2004||B.S., Mechanical engineering, Iowa State University, Ames, IA|