Biosensor using whispering gallery modes in microspheres

摘要

A biosensor for detecting the presence of a target analyte is disclosed. The biosensor is formed from microspheroidal particles which have had a binding partner for the target analyte immobilized on their surfaces. The binding partners may be nucleotides; peptides, proteins, enzymes, antibodies and so on. When the analyte binds to its partner, the whispering gallery mode (WGM) profiles of the micro spheroidal particles change such that the profile peaks undergo a red- or blue-shift. The immobilized binding partners may include fluorophores and the like so that they emit fluorescence, phosphorescence, incandescence and the like. These fluorophores may take the form of a nanocrystal or quantum dot.

主权项

1. A method of detecting multiple analytes in a sample, said method comprising:
(a) contacting multiple sets of microspheroidal particles with a sample putatively comprising said analytes, wherein each particle within a set of microspheroidal particles comprises an optically detectable label conjugated to an outer surface of the microspheroidal particles and an immobilized putative binding partner or binding partners of an analyte, wherein each set of microspheroidal particles has a different immobilized binding partner or binding partners of an analyte, a different microspheroidal particle size, and a different optically detectable label, and wherein each particle set has a defined Whispering Gallery Mode (WGM) profile, wherein binding of an analyte to said immobilized binding partner or binding partners results in a change in said WGM profile indicated by a spectral shift in the optically detectable label of a set of microspheroidal particles, which is indicative of the presence of said analyte, and (b) detecting binding of analytes to said multiple sets of microspheroidal particles by using a confocal microscope or an array scanner in conjunction with a spectrometer to detect spectral shifts in the WGM profiles of each set of microspheroidal particles, wherein said spectral shifts are in one or more emission peaks of each optically detectable label.