Microfluidic analysis system

Abstract

A microfluidic analysis system ( 1 ) performs polymerase chain reaction (PCR) analysis on a bio sample. In a centrifuge ( 6 ) the sample is separated into DNA and RNA constituents. The vortex is created by opposing flow of a silicon oil primary carrier fluid effecting circulation by viscous drag. The bio sample exits the centrifuge enveloped in the primary carrier fluid. This is pumped by a flow controller ( 7 ) to a thermal stage ( 9 ). The thermal stage ( 9 ) has a number of microfluidic devices ( 70 ) each having thermal zones ( 71, 72, 73 ) in which the bio sample is heated or cooled by heat conduction to/from a thermal carrier fluid and the primary carrier fluid. Thus, the carrier fluids envelope the sample, control its flowrate, and control its temperature without need for moving parts at the micro scale.

1 - 20 . (canceled) 
     
     
         21 . A method for analyzing a sample, the method comprising:
 flowing sample droplets enveloped in an immiscible carrier fluid to an analysis stage; and   analyzing the flowing droplets at the analysis stage, wherein the sample droplets do not contact a surface of the analysis stage.   
     
     
         22 . The method according to  claim 21 , wherein the sample comprises nucleic acid molecules 
     
     
         23 . The method according to  claim 22 , wherein prior to analyzing, the method further comprises amplifying the nucleic acid molecules. 
     
     
         24 . The method according to  claim 23 , wherein amplifying is by a polymerase chain reaction. 
     
     
         25 . The method according to  claim 21 , wherein analyzing comprises optically detecting fluorescent tags on molecules in the sample. 
     
     
         26 . The method according to  claim 21 , wherein flowing is continuously flowing. 
     
     
         27 . The method according to  claim 21 , wherein the carrier fluid is a biologically non-reactive fluid. 
     
     
         28 . The method according to  claim 27 , wherein the biologically non-reactive fluid is silicone oil. 
     
     
         29 . A method of diagnosing cancer in a subject, the method comprising:
 flowing sample droplets enveloped in an immiscible carrier fluid to an analysis stage, wherein the sample droplets comprise nucleic acid molecules, at least some of which are suspected of having mutations that are indicative of a cancer;   amplifying the nucleic acid molecules in the droplets;   hybridizing labeled probes to the nucleic acid molecules in the droplets, wherein the probes are specific for the mutations indicative of the cancer; and   detecting the labeled nucleic acids in the droplets at the analysis stage, wherein the droplets do not contact a surface of the analysis stage.   
     
     
         30 . The method according to  claim 29 , wherein amplifying is by the polymerase chain reaction. 
     
     
         31 . The method according to  claim 29  wherein the labeled probes are fluorescently labeled probes. 
     
     
         32 . The method according to  claim 29 , wherein flowing is continuously flowing. 
     
     
         33 . The method according to  claim 29 , wherein the carrier fluid is a biologically non-reactive fluid. 
     
     
         34 . The method according to  claim 33 , wherein the biologically non-reactive fluid is silicone oil. 
     
     
         35 . A biological sample analysis system, the system comprising:
 an analysis stage comprising an inlet and an outlet, wherein the inlet receives a flow of sample droplets enveloped in an immiscible carrier fluid, wherein the droplets do not contact a surface of the analysis stage and the droplets are analyzed as they flow to the outlet of the stage.   
     
     
         36 . The system according to  claim 35 , further comprising a thermal cycling stage configured such that the enveloped droplets flow through the thermal cycling stage prior to reaching the inlet of the analysis stage. 
     
     
         37 . The system according to  claim 36 , further comprising a sample preparation stage fluidly coupled to the analysis stage. 
     
     
         38 . The system according to  claim 35 , wherein the flow is a continuous flow. 
     
     
         39 . The method according to  claim 35 , wherein the carrier fluid is a biologically non-reactive fluid. 
     
     
         40 . The method according to  claim 39 , wherein the biologically non-reactive fluid is silicone oil.