Self-contained microfluidic biochip and apparatus

Abstract

A biochip and apparatus is disclosed for performing biological assays in a self-contained microfluidic platform. The disposable biochip for multi-step reactions comprises a body structure with a plurality of reagent cavities and reaction wells connected via microfluidic channels; the reagent cavities with reagent sealing means for storing a plurality of reagents; the reagent sealing means being breakable and allowing a sequence of reagents to be released into microfluidic channel and reaction well; and the reaction well allowing multi-step reactions to occur by sequentially removing away the residual reagents. The analysis apparatus can rapidly, automatically, sensitively, and simultaneously detect and identify multiple analytes or multiple samples in a very small quantity.

1 . A method of gene expression profiling or screening of candidate genes for a genetic study comprising steps of: 
 a) procurement means for simultaneous nucleic acid synthesis;    b) treatment means for nucleic acid amplification and labeling of at least one nucleic acid element; and    c) analyzing means for at least single-color hybridization to an integrated array of spotted bio-molecules where all three means are performed in a self-contained disposable microfluidic biochip apparatus, the apparatus comprising: a body structure comprising a plurality of reagent cavities and at least one reaction well connected via microfluidic channels, said reagent cavities each storing a reagent and each comprising a breakable seal allowing said reagent to be selectively released into said reaction well upon being punctured.    
     
     
         2 . The method of  claim 1 , wherein all steps are performed in the apparatus for out-lab use in a remote area.  
     
     
         3 . The method of  claim 1 , wherein said microfluidic channels have a dimension between about 0.1 μm and 2 mm in cross section.  
     
     
         4 . The method of  claim 1 , wherein said microfluidic channels have a dimension between about 1 μm and 50 μm in cross section.  
     
     
         5 . The method of  claim 1 , wherein a surface of the microfluidic channels is treated with a surface tension reducing agent.  
     
     
         6 . The method of  claim 5 , wherein the surface reducing agent is a fluorinated material.  
     
     
         7 . The method of  claim 5 , wherein the surface reducing agent is a hydrophilic material.  
     
     
         8 . The method of  claim 5 , wherein the surface reducing agent is a wetting agent.  
     
     
         9 . The method of  claim 1 , wherein said reaction well is facilitated with at least one biological probe that is selected from a group consisting of proteins, nucleic acids, receptors, and cells.  
     
     
         10 . The method of  claim 1 , wherein the biochip comprises a plurality of reaction wells, each being in flow communication with said plurality of reagent cavities.  
     
     
         11 . The method of  claim 1 , wherein the apparatus further comprises a vacuum suction for removing waste from said reaction well.  
     
     
         12 . The method of  claim 1 , wherein at least one of said reagent cavities comprises a second reagent stored in a chamber with a second breakable seal, whereby the second reagent flows and interacts with any other reagent in a reagent cavity when said second breakable seal is punctured.  
     
     
         13 . The method of  claim 1 , wherein said seal comprises a thin film located at the bottom of each reagent cavity for preventing reagent escape, and wherein each said reagent cavity comprises a microcap assembly located at the top of each reagent cavity, a pin being provided at adjacent said film configured for puncturing said film.  
     
     
         14 . The method of  claim 13 , wherein the apparatus further comprises a microactuator, wherein the microactuator and the biochip are supported for motion relative to each other configured and adapted for positioning the microactuator at each of the microcap assembly, wherein said microactuator is structured and configured to deliver a downward pressure to said microcap assembly.  
     
     
         15 . The method of  claim 1 , wherein the genetic study comprises a research of immune and infectious diseases.  
     
     
         16 . The method of  claim 1 , wherein the genetic study comprises a research of drug target identification and validation.  
     
     
         17 . The method of  claim 1 , wherein the genetic study comprises a research of identification of a threat agent selected from a group consisting of bacteria, viruses, germs, enzymes, fungi, and combination thereof.  
     
     
         18 . The method of  claim 1 , wherein the procurement means for simultaneous nucleic acid synthesis comprises three different reaction steps of a reverse transcription step, a formation of double-stranded cDNA step, and an isothermal amplification step.  
     
     
         19 . The method of  claim 1 , wherein the treatment means for nucleic acid amplification and labeling of at least one nucleic acid element comprises fluorescence labeling of the cDNA in a simple chemical reaction by coupling of NHS-ester cyanine 3 or cyanine 5 to aminoallyl groups of the cDNA.