AVS 57th International Symposium & Exhibition
    Biomaterial Interfaces Friday Sessions
       Session BI+MN-FrM

Paper BI+MN-FrM5
Elastomeric Microparticles that Exhibit Negative Acoustic Contrast in Bioassays

Friday, October 22, 2010, 9:40 am, Room Taos

Session: Sensors & Fluidics for Biomedical Applications
Presenter: K.W. Cushing, University of New Mexico
Authors: K.W. Cushing, University of New Mexico
M.E. Piyasena, University of New Mexico
B.A. Lopez, University of New Mexico
N. Carroll, University of New Mexico
T. Woods, University of New Mexico
D.N. Petsev, University of New Mexico
S. Graves, University of New Mexico
G.P. Lopez, Duke University
Correspondent: Click to Email
The development of more sensitive and rapid medical assays is imperative to decreasing time-to-diagnosis in diseased state individuals, and thus to improving patient outcomes. Enhanced detection limits afford the ability to detect the presence of low concentrations of biomarkers that may be present during the early-onset stages of a disease. Reduction in sample preparation requirements can further decrease assay time and the expertise level of the user. Our research aims to develop a sensitive and rapid bioassay platform using elastomeric capture microparticles (ECµPs) coupled to an acoustic sample preparation chamber and a flow cytometer. ECµPs possess unique physical and mechanical properties enabling the separation of ligand-bound ECµPs from biological particles (e.g., red blood cells) within a collected fluid sample (e.g., whole blood) by placing them under acoustic pressure. ECµPs have acoustic properties (negative contrast) that allow their positioning separately from many biological particles, which typically exhibit positive contrast, (e.g., cells) within an acoustic pressure field. Hence, an in-line acoustic sample preparation instrument can be used to separate unwanted biological particles (along with interfering soluble molecules) from ligand-bound ECµPs within biological fluids, The acoustic field will also concentrate the ECµPs, and so combined with removal of unwanted biological particles, much higher analysis rates of ECµPs may be possible. Since the acoustic sample preparation system operates continuously and can be mounted to feed separated ECµPs directly into a flow cytometer, this approach may decrease sample preparation time. Our studies show that simple emulsion polymerization methods using commercially available silicone precursors can be used to easily form elastomeric microparticles that exhibit negative contrast.