Quantification of Biomolecules Based on Flow Cytometric Single-Molecule Detection and Sorting on a Microchip

Johns Hopkins University, Baltimore MD

Investigators

Abstract

This award supports the development of a novel instrument for measurement of biomolecules using a combination of microscopy and a microfabricated device to provide high throughput, single-molecule detection capability. The instrument, which will sort and detect individual biomolecules during continuous flow, represents a significant enhancement in sensitivity, accuracy, and resolution in comparison to existing technology. The proposal aims to develop a generic, washing-free, sensing strategy that can identify specific nucleic acids and proteins in liquids at the single-molecule level using multi-channel confocal laser induced fluorescence (LIF) and fluorescence correlation spectroscopy (FCS), employing quantum dots as fluorescent tags. As part of the project, a functional microfluidic chip will be designed and fabricated to enable rapid and efficient molecular sorting. The microchip will have an array of microchannels for multiple, concurrent measurements. This will allow analysis with extremely low sample volume and concentration, and multiplexing of measurements to provide high-throughput. The proposed instrument will be useful in many bioanalytical areas including gene expression profiling, genotyping, early disease diagnostics, pharmaceutical screening, as well as the study of molecular binding. The impact of the project will extend beyond research to education and training at several levels and, potentially, commercial applications following further development.