Detector for measuring fluorescence in a liquid sample

Abstract

The present invention relates to a detector for measuring fluorescence in a liquid sample and to devices for biochemical analyses comprising it, in particular to devices for performing analyses of real time PCR. The detector of the present invention has a series of advantages such as drastic simplification of the detection configuration, reduced costs, better performances due to the greater freedom in planning the optical configuration which allows dividing the detector itself into independent areas.

1 . A detector for measuring fluorescence in a liquid sample comprising:
 an optical sensor, particularly of the CMOS type;   an optical unit;   means for connecting said optical sensor to said optical unit, said optical unit comprising:   a light source for irradiating said liquid sample;   a plurality of optical filters;   a plurality of lenses;   a first element having a plurality of portions separated from one another wherein a filter of said plurality of optical filters and a lens of said plurality of optical filters are housed in each one of said portions,   
       characterized in that the areas of said optical sensor is divided into a number of partitions m corresponding to the number n of the portions of said first element. 
     
     
         2 . The detector of  claim 1  wherein said filters have different wavelength. 
     
     
         3 . The detector of  claim 1  wherein said optical unit further comprises a window facing towards said liquid sample and transparent at a defined wavelength. 
     
     
         4 . The detector of  claim 1  further comprising means for securing said optical unit in said detector. 
     
     
         5 . The detector of  claim 1 , wherein the optical unit and the sensor are arranged perpendicularly to the longitudinal axis corresponding to the plane wherein a reaction area of the liquid sample under examination is positioned. 
     
     
         6 . The detector of  claim 1 , wherein said optical sensor and said optical unit are arranged on the same side wherein a reaction area of the liquid sample under examination is positioned. 
     
     
         7 . The detector of  claim 1  wherein light emitted in a determined area of said liquid sample is detected by a specific partition of said sensor corresponding to a portion of said first element. 
     
     
         8 . The detector of  claim 1  wherein said number of partitions m corresponding to the number n of the portions of said first element is equal to 4. 
     
     
         9 . A device for performing biochemical analyses, in particular for performing analyses of real time PCR, comprising a detector according of  claim 1 . 
     
     
         10 . The device according to  claim 9  comprising means for electrical and/or impedance measurements and a sample-holding cartridge, wherein said cartridge comprises:
 a plate made of thermally conductive material; 
 a cover for sealing said cartridge made of a transparent material to allow the passage of said light source; 
 an electrical interface for electrically connecting said cartridge to said means for electrical measurements and/or impedance. 
 
     
     
         11 . The device of  claim 10  wherein said cartridge further comprises a frame placed around said plate apt to handle said cartridge after loading said sample. 
     
     
         12 . The device of  claim 9  comprising:
 a mechanical handling system for the insertion and extraction of a sample-holding cartridge within said device, wherein said mechanical system comprises a pressure unit comprising a pressure plate and a frame mechanically fixed to said pressure plate whereby the movement and the closing pressure is transmitted to said pressure plate. 
 
     
     
         13 . The device of  claim 12  wherein said mechanical system further comprises:
 a first slide frame and a second movable frame, wherein said first frame is integral with said device and linked to said second frame via a slide mechanism; 
 means are fastened on said movable frame to exert pressure on said pressure plate. 
 
     
     
         14 . The device of  claim 13  wherein said means to exert pressure on said pressure plate comprises:
 first elements and second elements spaced apart therebetween by springs and a plurality of screws, wherein said second elements engage on said screws so as to push downwards said pressure plate. 
 
     
     
         15 . The device of  claim 10  further comprising an optical window positioned on a lower face of said sample-holding cartridge. 
     
     
         16 . The device of  claim 10  further comprising an adhesive and thermal conductive film positioned on an upper face of said sample-holding cartridge. 
     
     
         17 . The device of  claim 9  having a configuration wherein said light source irradiates said liquid sample from bottom upwards. 
     
     
         18 . The device of  claim 10  comprising a heating element positioned above said sample-holding cartridge so that a surface of said element enters in contact with an upper surface of said sample-holding cartridge.