Microparticle-based methods and systems and applications thereof

Abstract

Microparticle-based analytical methods, systems and applications are provided. Specifically, the use of resonant resonant light scattering as an analytical method for determining either or both a particle's identity and the presence and optionally, the concentration of one or more particular target analytes is described. Applications of these microparticle-based methods in biological and chemical assays are also disclosed.

1 - 59 . (canceled)  
     
     
         60 . A microparticle based measuring system comprising: 
 (a) at least one substantially spherical identifiable particle in solution, each particle comprising;    (a) a capture probe affixed to the outer surface of the particle; wherein:    1) the particle is characterized by a unique resonant light scattering signature when scanned over an analytical wavelength range having a window spanning about 1 to about 20 nanometers, over a range of optical wavelengths from about 275 to about 1900 nanometers;    2) the particle is about 75 micrometers in diameter or less; and    3) the particle has a refractive index between about 1.45 and about 2.1 over the analytical wavelength range.    (b) a light scanning source for scanning the particle over the analytical wavelength range;    (c) an optical cell for presenting the particle in a suitable position and in a suitable environment for detecting scattered light;    (d) a particle handling means for placing particles into the optical cell; and    (e) a detection means for detecting light from the scanned particle and converting said light to an electrical signal.    
     
     
         61 . A system of  claim 60  optionally comprising a means for contacting the particles with reagents and analytes.  
     
     
         62 . A system of  claim 60  optionally comprising a computer operably linked to the light scanning source and the detection means for the acquisition and analysis of said electrical signal generated by said detection means.  
     
     
         63 . A system of  claim 60  optionally comprising a data analysis means for converting said electrical signal to the identity of the particle and optionally the presence or degree of binding of an analyte or group of analytes to the particle.  
     
     
         64 . A system of  claim 60  optionally having a data analysis means for detecting binding of or identifying said analyte or group of analytes.  
     
     
         65 . A system of  claim 60  wherein the scanned light is generated by a source selected from the group consisting of a scanning diode laser, a tunable diode laser, and a polychromatic light source.  
     
     
         66 . A system of  claim 65  wherein the scanned light source is used with a wavelength-selecting device.  
     
     
         67 . A system of  claim 60  wherein the scanned light source is modified with a fiber optic light coupling means.  
     
     
         68 . A system of  claim 66  wherein said wavelength-selecting device optionally comprises components selected from the group consisting of; a dispersive element, a non-dispersive element, a monochromator, a tunable filter, a prism, a grating, and a fixed filter.  
     
     
         69 . A system of  claim 60  wherein the scattered light from one or more particles is detected with an imaging means.  
     
     
         70 . A microparticle based measuring system comprising according to  claim 66  wherein the imaging means comprises: 
 (a) a scanning diode laser light source;    (b) an optical cell suitable for spectroscopic scattered light imaging and stray light rejection;    (c) a means for contacting microparticles with analytes and reagents;    (d) a microscope;    (e) a digital camera and monitor;    (f) digital image acquisition hardware;    (g) a computer operably linked to the elements of (a)-(f) as needed and    (h) software suitable for controlling the elements of (a)-(f), capturing data, and processing the data.