Method and a system for quantitative or qualitative determination of a target component

Abstract

A method and a system for quantitative or qualitative determination of a target component in a liquid sample. The method includes i) providing a plurality of magnetic particles including capture sites for the target component on their respective surfaces; ii) providing a plurality of fluorophores configured to bind to the capture sites of the magnetic particles; iii) bringing the liquid sample into contact with the fluorophores and the magnetic particles in a flow channel of a micro fluidic device including a transparent window; and iv) at least temporally immobilizing the magnetic particles adjacent to the transparent window using a magnet, emitting exciting electromagnetic beam towards the immobilized magnetic particles, reading signals emitted from fluorophores and performing a quantitative or qualitative determination of the target component based on the read signal. A suitable micro fluidic device for use in the method/system and a kit for preparing a liquid sample.

1 . A system for quantitative or qualitative determination of a target component in a liquid sample, the system comprises
 a micro fluidic device comprising at least one flow channel with a transparent window and an inlet for the liquid sample;   a plurality of magnetic particles comprising capture sites for the target component on their respective surfaces;   a plurality of fluorophores configured to bind to said capture sites of the magnetic particles or to said target component;   a magnet arranged to at least temporally immobilize said magnetic particle adjacent to said transparent window;   an emitter for exciting said fluorophores, and   a reader for reading signals emitted from said fluorophores,   wherein the micro fluidic device comprises a flexible wall section of the flow channel or of a sink section in fluid connection with the flow channel and the system comprises an actuator, which is adapted to move the flexible wall section for feeding a liquid sample into the flow channel.   
     
     
         2 . The system of  claim 1 , wherein the micro fluidic device comprises polymer and comprises a substrate with a groove for the flow channel and a foil covering the flow channel. 
     
     
         3 . The system of  claim 1 , wherein the inlet of the micro fluidic device is an inlet for suction in a liquid sample. 
     
     
         4 . The system of  claim 1 , wherein the actuator is a step motor driven actuator. 
     
     
         5 . The system of  claim 1 , wherein the inlet and the actuator are arranged such that the upon activation of the actuator, the flexible wall section will be moved and air will be pressed out of the flow channel where after the flexible wall will return to its initial position and a liquid sample will be sucked into the flow channel. 
     
     
         6 . The system of  claim 1 , wherein the micro fluidic device comprises two or more flow channels, wherein the two or more flow channels have a common inlet. 
     
     
         7 . The system of  1 , wherein the micro fluidic device comprises an excitation and a read out zone provided in the form of the transparent window, the window is transparent for at least the exciting and emitting wavelengths of the fluorophores. 
     
     
         8 . The system of  claim 1 , wherein the system comprises a temperature regulator for regulating the temperature of the liquid sample in the flow channel. 
     
     
         9 . The system of  claim 1 , wherein the magnetic particles are coated magnetic particles comprising a coating comprising the captures sites. 
     
     
         10 . The system of  claim 1 , wherein the fluorophores are configured to bind to said capture sites of the magnetic particles by being coupled to a component, which can bind to the capture sites of the magnetic particles. 
     
     
         11 . The system of  claim 10 , wherein the component is identical to or homolog to said target component so that the component is also able to bind to said capture sites of the magnetic particles. 
     
     
         12 . The system of  claim 1 , wherein the fluorophores comprising at least one capture site for the target component to provide that the target component may bind to at least one of the fluorophores. 
     
     
         13 . The system of  claim 1 , wherein said fluorophores and said magnetic particles are temporally immobilized in said flow channel of the micro fluidic device such that they cannot bind to each other prior to feeding of a liquid sample to said flow channel. 
     
     
         14 . The system of  claim 1 , wherein said magnet is adapted to at least temporally immobilize said magnetic particle adjacent to said transparent wall section for a sufficient time to excite at least a part of possible fluorophores captured by said capture sites of the magnetic particles by the emitter and to read out any emitted signal from such excited captured fluorophores. 
     
     
         15 . The system of  claim 1 , wherein said emitter comprises at least one optical fiber with an output end for emitting said electromagnetic radiation and said reader comprises at least one optical fiber with an input end for receiving said signals emitted from fluorophores captured by magnetic particles, said optical fiber of the emitter and said optical fiber of the reader are arranged adjacent to each other in at least respective length sections adjacent to respectively the output end and the input end. 
     
     
         16 . The system of  claim 14 , wherein said emitter comprises a plurality of optical fibers, each fiber having an output end for emitting said electromagnetic radiation and said reader comprises a plurality of optical fibers, each fiber having an input end for receiving said signals emitted from fluorophores captured by magnetic particles, said optical fibers of the emitter and said optical fibers of the reader are arranged adjacent to each other in at least respective length sections adjacent to respectively the output end and the input. 
     
     
         17 . A micro fluidic device for use in preparing a liquid sample for optical analysis for quantitative or qualitative determination of a target component in a sample, the micro fluidic device comprising at least one flow channel with a transparent window and an inlet for the liquid sample, the micro fluidic device further comprises in its flow channel
 a plurality of magnetic particles comprising capture sites for the target component on their surfaces; and   a plurality of fluorophores configured to bind the capture sites of the magnetic particles or to said target component   wherein said fluorophores and said magnetic particles are temporally immobilized in said flow channel of the micro fluidic device such that they cannot bind to each other prior to feeding of a liquid sample to said flow channel and   wherein the micro fluidic device comprises a flexible wall section of the flow channel or of a sink section in fluid connection with the flow channel, said flexible wall section being capable of being moved by an actuator for feeding a liquid sample into the flow channel.   
     
     
         18 . A micro fluidic device of  claim 17 , wherein the micro fluidic device comprising a substrate with a groove for the flow channel and a foil covering the flow channel, wherein the flexible wall section is movable to provide that air will be pressed out of the flow channel where after the flexible wall will return to its initial position. 
     
     
         19 . A micro fluidic device for use in quantitative or qualitative determination of target component in a sample, the micro fluidic device comprising at least one flow channel with a transparent window and an inlet for the liquid sample,
 wherein the micro fluidic device comprises a flexible wall section of the flow channel or of a sink section in fluid connection with the flow channel, said flexible wall section being capable of being moved by an actuator for feeding a liquid sample into the flow channel, wherein the micro fluidic device comprising a substrate with a groove for the flow channel and a foil covering the flow channel, wherein the flexible wall section provides said flexible wall section and is movable to provide that air will be pressed out of the flow channel where after the flexible wall will return to its initial position.