Waveguide localized raman spectroscopy

Abstract

A Raman spectroscopic detection device comprising at least one microfluidic sample channel; at least one excitation waveguide for exciting a Raman signal and at least one collection waveguide for collecting a Raman signal. The output of the excitation waveguide and the input of the collection waveguide are positioned directly in the microfluidic sample channel.

1 . A Raman spectroscopic detection device comprising:
 at least one microfluidic sample channel; and   at least one of:
 at least one excitation waveguide for exciting a Raman signal, wherein the at least one excitation waveguide is positioned so that its output end is in the at least one microfluidic sample channel; or 
 at least one collection waveguide for collecting a Raman signal, wherein the at least one collection waveguide is positioned so that its input end is in the at least one microfluidic sample channel. 
   
     
     
         2 . A device as claimed in  claim 1  wherein the at least one collection waveguide or the at least one excitation waveguide is an optical fiber. 
     
     
         3 . A device as claimed in  claim 1  wherein the at least one excitation waveguide or the at least one collection waveguide is embedded in the detection device. 
     
     
         4 . A device as claimed in  claim 1  wherein said detection device comprises at least one excitation waveguide, and wherein no optical elements are between an end of the at least one excitation waveguide and the at least one microfluidic sample channel to modify an output beam profile of the at least on excitation waveguide. 
     
     
         5 . A device as claimed in  claim 1  wherein said detection device comprises at least one collection waveguide, and wherein no optical elements are between an end of the at least one collection waveguide and the at least one microfluidic sample channel. 
     
     
         6 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein a distance between an end of an excitation waveguide and a corresponding collection waveguide is of the order of size of a core of each waveguide. 
     
     
         7 . A device as claimed in  claim 1  wherein the at least one microfluidic sample channel is at least part of a microfluidic channel that allows fluid to flow therethrough. 
     
     
         8 . A device as claimed in  claim 7  wherein means are provided for causing a fluid flow through the microfluidic channel. 
     
     
         9 . A device as claimed in  claim 1  wherein the size of the at least one microfluidic sample channel is <500 μm. 
     
     
         10 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein ends of a excitation waveguide and a corresponding collection waveguide define the sample detection volume. 
     
     
         11 . A device as claimed in  claim 1  where diverging or collimated excitation beam samples substantially interrogated an entire cross section of the at least one microfluidic sample channel. 
     
     
         12 . A device as claimed in  claim 1  further integrated with one or more functional microfluidic device. 
     
     
         13 . A device as claimed in  claim 12  wherein the functional microfluidic device comprises a microfluidic device adapted to generate micro-droplets or a microreactor for allowing one or more reactions to occur within the functional microfluidic device. 
     
     
         14 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein an excitation waveguide and a corresponding collection waveguide are mutually orthogonal. 
     
     
         15 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein the at least one microfluidic sample channel, the excitation waveguide, and the collection waveguide have substantially the same peripheral dimensions. 
     
     
         16 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein the at least one microfluidic sample channel, an excitation waveguide, and a corresponding collection waveguide are arranged in a cross configuration. 
     
     
         17 . A device as claimed in  claim 1  wherein said detection device comprises both at least one excitation waveguide and at least on collection waveguide, and wherein the at least one microfluidic sample channel, one of the excitation waveguides, and a corresponding collection waveguide are arranged in a T configuration. 
     
     
         18 . A device as claimed in  claim 1  wherein an end of at least one of the excitation waveguide or the collection waveguide is treated. 
     
     
         19 . A device as claimed in  claim 16  wherein an end of the excitation waveguide or the collection waveguide is coated with an optically active material. 
     
     
         20 . A device as claimed in  claim 16  wherein an end of the excitation waveguide or the collection waveguide is coated with a filter material. 
     
     
         21 . A device as claimed in  claim 1  wherein an end of at least one of the excitation waveguide or the collection waveguide is shaped. 
     
     
         22 . A device as claimed in  claim 1  wherein said detection device comprises at least on collection waveguide, and wherein the excitation signal causes fluorescence, as well as a Raman signal, and the collection waveguide collects the fluorescence signal as well as the Raman signal.