Eager: Elastomeric Capture Microparticles For High Sensitivity Biodection

<p>Intellectual Merit: Separation prior to biospecific interaction based detection can significantly increase signal-to-noise level and thus can enhance specificity, sensitivity, and confidence in biosensing measurements. Separations based on biospecific interaction of microparticles in suspension are particularly attractive because convective and diffusional limitations to ligand binding can be minimized, while at the same time obviating the need for high pressure pumping though membranes or columns. Furthermore, receptor site occupancy of microparticles can be routinely analyzed by common laboratory methods such as flow cytometry or plate reading. This proposal demonstrates proof-of-concept for acoustic separation of microparticles and illustrate how this phenomenon can be developed into a continuous separation strategy for enhanced biosensing of molecular, viral and cellular analytes. Separation of a target analyte from a complex sample milieu (e.g., blood or other cell-containing suspension) is accomplished by displaying biomolecular receptors on elastomeric microparticles that exhibit negative contrast in acoustic standing waves imposed on microfluidic streams. Acoustic radiation results in the separation of elastomeric microparticles from incompressible particles such as cells. Removal of the target analyte from the complex sample components allows precise chemical analysis, e.g., by fluorometric, electrophoretic or mass spectrometric means. This project will execute three distinct tasks including synthesis of stable elastomeric miroparticles, modification of these microparticles for biospecific interaction, and validation of separation and detection methods for molecular and cellular analytes. Achievement of these tasks will thus provide the fundamental basis by which elastomeric particles can be used in conjunction with acoustic separations for high performance bioanalytical manipulations. Broader Impacts: This preliminary work will form the basis for the use of new types of elastomeric microparticles in a number of biosensing modalities, including biomolecular sensing, rare cell detection and cell isolation. The principles, materials and methods developed will be applicable to biodetection in a number of contexts including food safety, environmental monitoring, process control and national defense. This work will also establish methods for materials synthesis and biofunctionalization that will enable the examination of elastomeric micro- and nanoparticles for in vivo imaging, sensing and targeted drug delivery. This project will support the salary of a female biochemist postdoctoral fellow, whose goal is to gain further experience in the field of biosensor science and engineering. Through this project, she will also gain valuable experience in several aspects of biomedical engineering, including biomaterial interfacial engineering, microfluidics and bioanalytical instrumentation. The personnel on this project will be augmented by taking advantage of human resources available at Duke, including undergraduate researchers (e.g., supported by NSF REU program or Duke Pratt Fellows program) and Masters level graduate students who conduct independent study research for graduate credit. Each of these mechanisms will be used to enhance the educational and research training impact of this project.</p>