Fiber optical assembly for fluorescence spectrometry

Abstract

System and method for analyzing a sample for the presence of an analyte in a sample, the system comprising a sample holder for containing the sample; an excitation source in optical communication with the sample, wherein radiation from the excitation source is directed to the sample, and wherein the radiation induces a fluorescence signal; and at least one linear array comprising a proximal end disposed in proximity to the sample holder and an end port distal from the proximal end; a plurality of optical fibers extending from the proximal end to the end port and having a first end and a second end, wherein the first ends of the individual optical fibers are substantially coplanar and adjacent to one another, and wherein the second ends of the optical fibers form a non-linearly arranged bundle, and wherein the plurality of optical fibers transmits the fluorescent signal from the proximal end to the end port; and an end port assembly optically coupled to the end port, the end port assembly comprising a single photo-detector, wherein the photo-detector detects the fluorescent signal and converts the fluorescent signal into an electrical signal.

1 . A system for analyzing a sample for the presence of an analyte in a sample, the system comprising:
 a. a sample holder for containing the sample;   b. an excitation source in optical communication with the sample, wherein radiation from the excitation source is directed to the sample, and wherein the radiation induces a fluorescence signal; and   c. at least one linear array comprising:
 i. a proximal end disposed in proximity to the sample holder and an end port distal from the proximal end; 
 ii. a plurality of optical fibers extending from the proximal end to the end port and having a first end and a second end, wherein the first ends of the individual optical fibers are substantially coplanar and adjacent to one another, and wherein the second ends of the optical fibers form a non-linearly arranged bundle, and wherein the plurality of optical fibers transmits the fluorescent signal from the proximal end to the end port; and 
 iii. an end port assembly optically coupled to the end port, the end port assembly comprising a single photo-detector, wherein the photo-detector detects the fluorescent signal and converts the fluorescent signal into an electrical signal. 
   
     
     
         2 . The system according to  claim 1 , further comprising an analyzer electrically coupled to the photo-detector, wherein the analyzer receives the electrical signal from the photo-detector and analyzes the sample for the presence of the analyte based upon the electrical signal. 
     
     
         3 . The system according to  claim 1 , wherein the linear array comprises from about 10 to about 100 optical fibers. 
     
     
         4 . The system according  claim 1 , wherein the system comprises at least two linear arrays. 
     
     
         5 . The system according to  claim 4 , wherein the linear arrays are disposed about the sample holder radially and substantially equidistantly with respect to each other. 
     
     
         6 . The system according to  claim 1 , wherein the excitation source is a laser. 
     
     
         7 . The system according to  claim 5 , wherein the laser is amplitude modulated. 
     
     
         8 . The system according the  claim 2 , wherein the analyzer is a phase-sensitive detector. 
     
     
         9 . The system according to  claim 1 , wherein the end port assembly further comprises at least one optical filter, wherein the at least one optical filter rejects radiation from the excitation source that is outside a detection bandwith of a predetermined analyte. 
     
     
         10 . The system according to  claim 1 , wherein the photo-detector is a photo-diode or a photo-multiplier. 
     
     
         11 . A linear array for detecting a fluorescent signal generated by a sample, the linear array comprising:
 a. a proximal end and an end port distal from the proximal end, wherein the end port is optically polished, and wherein the proximal end is disposed in proximity to the sample;   b. a plurality of optical fibers having a first end and a second end, wherein the first ends are substantially coplanar and adjacent to one another, and wherein the second ends of the optical fibers form a non-linearly arranged bundle which is in contact with the endport, and wherein the optical fibers transmit the fluorescent signal from the sample to the endport; and   c. an end port assembly optically coupled to the end port, the end port assembly comprising a single photo-detector, wherein the photo-detector detects the fluorescent signal and converts the fluorescent signal into an electrical signal.   
     
     
         12 . The linear array according to  claim 11 , further comprising an analyzer electrically coupled to the photo-detector, wherein the analyzer receives the electrical signal from the photo-detector and analyzes the sample for the presence of the analyte based upon the electrical signal. 
     
     
         13 . The linear array according to  claim 12 , wherein the analyzer is a phase-sensitive detector. 
     
     
         14 . The linear array according to  claim 11 , wherein the end port assembly further comprises at least one optical filter, wherein the optical filter rejects radiation from the excitation source that is outside a detection bandwith of a predetermined analyte. 
     
     
         15 . The linear array according to  claim 11 , wherein the photo-detector is a photo-diode or a photo-multiplier. 
     
     
         16 . The linear array according to  claim 11 , wherein the linear array comprises from about 10 to about 100 optical fibers. 
     
     
         17 . A method of analyzing a sample for the presence an analyte, the method comprising the steps of:
 a. providing a sample comprising the analyte to a sample holder;   b. disposing a proximal end of at least one linear array in proximity to the sample holder;   c. directing radiation from an excitation source to the sample, wherein the radiation causes the sample to generate a fluorescent signal;   d. receiving the fluorescent signal from the sample at the proximal end;   e. transmitting the fluorescent signal to a photo-detector in the linear array;   detecting the fluorescent signal with the photo-detector;   g. converting the fluorescent signal to an electrical signal; and   h. analyzing for the presence of the analyte based on the electrical signal.   
     
     
         18 . The method according to  claim 17 , wherein the linear array comprises a plurality of optical fibers having a first end and a second end, wherein the first ends are substantially coplanar and adjacent to one another. 
     
     
         19 . The method according  claim 17 , wherein at least two linear arrays are disposed in proximity to the sample holder. 
     
     
         20 . The method according to  claim 19 , wherein the linear arrays are disposed about the sample holder radially and substantially equidistantly with respect to each other.