Apparatus for Pathogen Detection

Abstract

An apparatus for separating an analyte from a test sample, such as bacteria from blood components, based on their dielectric properties, localizing or condensing the analyte, flushing substantially all remaining waste products from the test sample, and detecting low concentrations of the analyte. The module array includes a plurality of microfluidic channels with connecting microfluidic waste channels for directing undesired material away from the analyte. A detection method for separating and analyzing a contaminant using the apparatus allows for transporting a test sample having an analyte and a waste product through at least one microfluidic channel; generating dielectrophoretic forces on the test sample as the test sample is transported through the at least one microfluidic channel; trapping the test sample to separate the waste product from the analyte; separating the waste product from the analyte; and sensing, with a sensor, the analyte

Thus, having described the invention, what is claimed is: 
     
         1 . A detection method comprising:
 transporting a test sample including an analyte and a waste product through at least one microfluidic channel;   generating dielectrophoretic forces on said test sample as said test sample is transported through said at least one microfluidic channel;   trapping said test sample to separate said waste product from said analyte;   separating said waste product from said analyte; and   sensing, with a sensor, the analyte.   
     
     
         2 . The method of  claim 1  further including the step of condensing said analyte after the step of separating said waste product from said analyte. 
     
     
         3 . The method of  claim 2  further including condensing said analyte in a chamber. 
     
     
         4 . The method of  claim 2  further including the step of flushing said condensed analyte with a reference solution to remove substantially all remaining waste product from said condensed analyte. 
     
     
         5 . The method of  claim 4  wherein the condensed analyte is sensed with a sensor to detect the analyte in the test sample. 
     
     
         6 . The method of  claim 1  wherein the sensor is a microfluidic sensor. 
     
     
         7 . The method of  claim 1  wherein the dielectrophoretic forces generated on said test sample are via at least one electrode. 
     
     
         8 . The method of  claim 1  comprising flowing the test sample through the at least one microfluidic channel at a velocity of at least 100 μm/s. 
     
     
         9 . The method of  claim 1  wherein the test sample is a diluted test sample, and further including flowing the diluted test sample through the at least one microfluidic channel at a flow rate around 1 cc per minute. 
     
     
         10 . A method for capturing a contaminant material from a sample comprising:
 providing a microfluidic separator for trapping said contaminant material to be analyzed and/or separated comprising at least one electrode, and a primary microfluidic channel with an inlet and an outlet; and   trapping the contaminant material in the microfluidic separator.   
     
     
         11 . The method of  claim 10  wherein the contaminant material is a microorganism, bacteria, pathogen, or virus. 
     
     
         12 . The method of  claim 10  wherein the step of trapping the contaminant material in the microfluidic separator is achieved by applying different AC electric fields to the at least one electrode of the microfluidic separator. 
     
     
         13 . The method of  claim 10  wherein the step of trapping the contaminant material in the microfluidic separator is achieved by applying different AC electric currents to the at least one electrode of the microfluidic separator. 
     
     
         14 . The method of  claim 10  further including:
 providing a sensor for sensing the contaminant material trapped and/or separated by said microfluidic separator having at least one electrode and a secondary microfluidic channel with an inlet and an outlet; 
 condensing the trapped contaminant material in the sensor; 
 closing the outlet of the primary microfluidic channel; 
 opening the inlet of the secondary microfluidic channel; 
 stopping the AC electric field applied to the at least one electrodes of the microfluidic separator; and 
 applying an AC electric field to the at least one electrode of the sensor to condense the contaminant material from the microfluidic separator in the sensor.