Device and method for investigating analytes in liquid suspension or solution

Abstract

An optical detection device is provided for analyzing analytes in a liquid suspension or solution that can detect and process a large number of wavelengths of incident and fluorescent light simultaneously, which is small in size and can be easily adapted to different investigation requirements. The optical detection device may include a light supplying device, an analyte handling device, a light directing device, and a detector integrated on planar substrate devices, respectively. A plurality of optical waveguides are integrated in the substrate devices to direct light emitted by the light supplying device through the different sections of the optical detector to the detector. The analyte handling device may include an analyte channel for the liquid flow of the analyte suspension or solution and an analyte sorting device comprising several sorting channels.

1 . A device for analyzing analytes in a liquid suspension or solution, comprising:
 a light handling unit for combining light from at least two light sources, comprising:
 a first substantially flat, unitary, planar substrate; 
 a plurality of input optical waveguides formed in or on the first planar substrate, each input optical waveguide conducting light output from a different one of a plurality of light sources; 
 a light combining element formed in or on the first planar substrate and having an input end coupled to output ends of the plurality of input optical waveguides, wherein the light combining element combines the light output from the plurality of input optical waveguides; and 
 an output optical waveguide formed in or on the first planar substrate and coupled to an output end of the light combining element, the output optical waveguide conducting the combined light away from the combining element; and 
   an analyte handling unit comprising:
 a second substantially flat, unitary, planar substrate; and 
 an analyte conveying channel formed in or on the second planar substrate, the analyte conveying channel carrying analytes in a liquid suspension or solution, the analyte conveying channel including an interrogation region, and wherein light output from the output optical waveguide of the light handling unit is coupled into the interrogation region. 
   
     
     
         2 . The device of  claim 1 , wherein the light combining element is a dispersive element. 
     
     
         3 . The device of  claim 2 , wherein the dispersive element is an arrayed waveguide grating. 
     
     
         4 . The device of  claim 2 , wherein the dispersive element is a transmission grating formed by an array of recesses that are etched into the planar substrate. 
     
     
         5 . The device of  claim 1 , further comprising a plurality of light sources mounted in or on the first planar substrate that emit light having different respective wavelength characteristics, wherein each light source is coupled to a respective one of the plurality of input optical waveguides of the light handling unit. 
     
     
         6 . The device of  claim 5 , wherein the plurality of light sources are mounted on the first planar substrate such that the light output from each light source is coupled into a respective one of the plurality of input optical waveguides. 
     
     
         7 . The device of  claim 5 , wherein the plurality of light sources are also integrated into the substrate in which the light handling unit is integrated. 
     
     
         8 . The device of  claim 5 , wherein the plurality of light sources comprise laser diodes. 
     
     
         9 . The device of  claim 1 , wherein the analyte handling unit further comprises an interrogation input optical waveguide formed in or on the second planar substrate, and wherein the output optical waveguide of the light handling unit on the first planar substrate is coupled to the interrogation input optical waveguide on the second planar substrate via an optical fiber connection between the first and second planar substrates. 
     
     
         10 . The device of  claim 1 , wherein the analyte conveying channel further comprises an analyte input region that receives analytes in a liquid suspension or solution that is conveyed by the analyte conveying channel into the interrogation region, and an analyte output region that receives analytes in a liquid suspension or solution from the interrogation region. 
     
     
         11 . The device of  claim 10 , wherein the analyte handling unit further comprises:
 at least one interrogation input optical waveguide formed in or on the second planar substrate that is coupled to the output optical waveguide of the light handing unit and that conducts light from the light handling unit into the interrogation region; and   at least one interrogation output optical waveguide formed in or on the second planar substrate that conducts light away from the interrogation region.   
     
     
         12 . The device of  claim 11 , wherein the at least one interrogation output optical waveguide comprises:
 a first output optical waveguide formed in or on the second planar substrate and located so as to receive forwarded scattered light emerging from the interrogation region; and   a second output optical waveguide formed in or on the second planar substrate and located so as to receive side scattered light emerging from the interrogation region at an angle to the forward scattered light.   
     
     
         13 . The device of  claim 12 , wherein the second output optical waveguide is located such that it collects light emerging from the interrogation region at an angle of between 60 and 120 degrees relative to light emerging from the interrogation region that is collected by the first output optical waveguide. 
     
     
         14 . A device for analyzing analytes in a liquid suspension or solution, comprising:
 a light generating unit including:
 a first substantially flat, unitary, planar substrate, 
 at least one light source that generates an interrogation light, and 
 an optical waveguide formed in or on the first planar substrate that conveys the interrogation light generated by the at least one light source; and 
   an analyte handling unit that includes:
 a second substantially flat, unitary, planar substrate; 
 an analyte conveying channel formed in or on the second planar substrate, the analyte conveying channel carrying analytes in a liquid suspension or solution, the analyte conveying channel including an interrogation region, 
 an input interrogation waveguide formed in or on the second planar substrate that conveys interrogation light into the interrogation region; and 
 at least one output interrogation waveguide formed in or on the second planar substrate that collects light from the interrogation region. 
   
     
     
         15 . The device of  claim 14 , wherein light output from the optical waveguide of the light generating unit is coupled to the input interrogation waveguide of the analyte handling unit by an optical fiber that passes between the light generating unit and the analyte handling unit. 
     
     
         16 . A method of delivering light to analytes in a liquid suspension or solution, comprising:
 receiving light from a plurality of light sources through a corresponding plurality of input optical waveguides at a light combining element, the light from each of the light sources having different respective wavelength characteristics, wherein the plurality of input optical waveguides and the light combining element are formed in or on a first substantially flat, unitary, planar substrate;   combining the light from the plurality of light sources in the combining element; and   coupling the combined light into analytes in a liquid suspension or solution contained in an interrogation region of an analyte conveying channel that is formed in a second substantially fiat, unitary, planar substrate, wherein the combined light is conveyed to the interrogation region through an output optical waveguide coupled to the combining element, the output optical waveguide also being formed in or on the first planar substrate.   
     
     
         17 . The method of  claim 16 , wherein the coupling step comprises:
 coupling the combined light from the output optical waveguide into an optical fiber coupled to the output optical waveguide on the first planar substrate;   conveying the combined light through the optical fiber to an interrogation input optical waveguide formed in or on the second planar substrate; and   conveying the combined light through the interrogation input optical waveguide into the interrogation region.   
     
     
         18 . The method of  claim 16 , wherein the combining step comprises multiplexing the light from the plurality of light sources with a dispersive element formed in or on the first planar substrate. 
     
     
         19 . The method of  claim 18 , wherein the multiplexing step comprises multiplexing the light from the plurality of light sources with a transmission grating formed by an array of recesses that are etched into the first planar substrate. 
     
     
         20 . The method of  claim 18 , wherein the multiplexing step comprises multiplexing the light from the plurality of light sources with an arrayed waveguide grating formed in or on the first planar substrate.