Fiber-optic biosensor and biosensing methods

Abstract

A biosensor device that includes a module defining at least one microfluidic channel, an optical waveguide exposed along at least a portion of its length to fluid flow within the microfluidic channel, where a surface of the optical waveguide being prepared to bind a target biomarker, and an excitation source to couple an excitation wavelength of light into the optical waveguide. The device also includes a sensor for detecting emission light from the optical waveguide at an emission wavelength characteristic of binding of the target biomarker. Particular devices include multiple waveguides in multiple microfluidic channels. Particular devices include microfluidic channels with serpentine bump structures that aid molecular transport.

What is claimed is: 
     
         1 . A biosensor for simultaneously detecting and quantifying two or more target biomarkers, the biosensor comprising:
 a housing;   a reservoir plate coupled to said housing, said reservoir plate having at least one inlet and at least one outlet and a microfluidic network fluidly coupling said inlet and said outlet;   a plurality of valves and at least one pump disposed within said microfluidic network;   a disposable biochip configured to be coupled to, and in fluid communication with, said reservoir plate, said biochip having four sensing channels disposed therein, each of said channels being configured to receive one of the optical sensing fibers;   a power source;   a drive circuit; and   a data acquisition card.   
     
     
         2 . An automatic, portable biosensor for simultaneously detecting and quantifying a plurality of target biomarkers for rapid disease diagnosis and prognosis, said biosensor comprising:
 a biochip having a plurality of microchannels disposed therein;   at least one optical waveguide configured to be disposed within a respective one of said microchannels, and being further configured to have an optimized sensing end portion on which to conduct a fluorophore mediated sandwich immunoassay;   a plurality of reagent reservoirs; and   a microfluidic network disposed between said biochip and said reagent reservoirs to maintain fluid communication between said biochip and said reagent reservoirs, said microfluidic network including a plurality of microchannels, a plurality of reagent valves corresponding to each of said reagent reservoirs, a pump, and a three way valve.   
     
     
         3 . The biosensor of  claim 2  further comprising four quartz optical sensing fibers coupled in series. 
     
     
         4 . The biosensor of  claim 3  further comprising optimized sensing portions disposed at a first end of said four quartz optical sensing fibers. 
     
     
         5 . The biosensor of  claim 2  further comprising a bubble trap for removing bubbles from the microchannels. 
     
     
         6 . The biosensor of  claim 2  further comprising a serpentine binding enhancer disposed within each of said microchannels. 
     
     
         7 . A biosensor device, said device comprising:
 a module defining at least one microfluidic channel;   an optical waveguide exposed along at least a portion of its length to fluid flow within said microfluidic channel, a surface of said optical waveguide being prepared to bind a target biomarker;   an excitation source to couple an excitation wavelength of light into said optical waveguide; and   a sensor for detecting emission light from said optical waveguide at an emission wavelength characteristic of binding of the target biomarker.   
     
     
         8 . The biosensor device of  claim 7 , said module further comprising four microfluidic channels. 
     
     
         9 . The biosensor device of  claim 8  further comprising four quartz optical sensing fibers, each of which is configured to be at least partially disposed within one of said four microfluidic channels and fluidly coupled to one another in series. 
     
     
         10 . The biosensor device of  claim 7 , wherein said microfluidic channel is configured to pass, via convective flow, a sample believed to contain one or more target biomarkers through over the surface of the optical waveguide. 
     
     
         11 . The biosensor device of  claim 7 , wherein said at least one microfluidic channel comprises four microfluidic channels, each of said microfluidic channels having an optical waveguide disposed at least partially therein, wherein each optical waveguide is prepared to bind one of the one or more target biomarkers. 
     
     
         12 . The biosensor device of  claim 7 , comprising at least two optical waveguides and two microfluidic channels, each of the at least two optical waveguides being disposed at least partially in a respective one of said two microfluidic channels, the at least two optical waveguides being fluidly coupled to one another in series. 
     
     
         13 . The biosensor device of  claim 12 , wherein each of said at least two microfluidic channels comprises a serpentine bump structure inside each of said at least two microfluidic channels. 
     
     
         14 . The biosensor device of  claim 7 , wherein said at least one microfluidic channel comprises a serpentine bump structure inside said at least one microfluidic channel. 
     
     
         15 . The biosensor device of  claim 7 , wherein the optical waveguide comprises optical sensing fibers optimized for a fluorophore mediated sandwich immunoassay, and wherein 1° and 2° monoclonal antibodies (Mabs) are provided on surfaces of the optical sensing fibers to correspond to a particular target biomarker. 
     
     
         16 . The biosensor device of  claim 7 , comprising at least two optical waveguides disposed in parallel to one another and fluidly connected to one another via communication channels.