Digital control of on-chip magnetic particle assay

Abstract

An assay system and method for use in the field of chemical testing is disclosed. The assay system can be used for filtering whole blood for testing on an integrated circuit containing digital control functionality.

1 . (canceled) 
     
     
         2 . An assay system for generating presentable assay information from an aqueous solution, comprising:
 a filter;   a surface capillary;   a delivery capillary, wherein the delivery capillary fluidly connects the filter to the surface capillary;   a sedimentation capillary, wherein the surface capillary fluidly connects the delivery capillary to the sedimentation capillary;   a dry sphere placed at the top of the sedimentation capillary, wherein the dry sphere contains magnetic particles, wherein the dry sphere is held motionless within a cuvette having vertical side walls, wherein the cuvette is configured to hold the aqueous solution and the dry sphere simultaneously;   an integrated circuit placed below the sedimentation capillary;   magnetic particle sensors embedded in the integrated circuit at the bottom of the sedimentation capillary, wherein the magnetic particle sensors are capable of detecting magnetic particles specifically bound to a surface of the integrated circuit; and   a display for displaying presentable assay information.   
     
     
         3 . The system of  claim 2 , wherein the cuvette comprises a flow stop placed above the dry sphere, wherein the flow stop seals the sedimentation capillary when the dry sphere dissolves. 
     
     
         4 . The system of  claim 2 , wherein a passive unidirectional valve is configured to eliminate and/or reduce the suck-back flow resulting from aqueous sample evaporation through the filter. 
     
     
         5 . The system of  claim 2 , wherein a magnetic particle sensor is configured to detect a single specific molecular interaction between the surface of the integrated circuit and a magnetic particle. 
     
     
         6 . The system of  claim 5 , wherein an array of magnetic particle sensors is configured to count the number of specific molecular interactions in a sensing area on the surface of the integrated circuit. 
     
     
         7 . The system of  claim 2 , wherein the sedimentation capillary comprises a notch, wherein the notch is configured to prevent the dry sphere from failing into the sedimentation capillary. 
     
     
         8 . The system of  claim 2 , wherein the cuvette comprises tapered sidewalls, wherein the tapered sidewalls are configured to hold the dry sphere in place within the sedimentation capillary. 
     
     
         9 . A method of generating presentable assay information from an aqueous solution, comprising:
 passing the aqueous sample through a filter into a delivery capillary;   delivering the aqueous sample from the delivery capillary to a surface capillary and from the surface capillary to a sedimentation capillary;   detecting the presence of a target analyte in the aqueous sample by introducing the aqueous sample to reacting magnetic particles within a dry sphere, the dry sphere being placed within a cuvette fluidly connected to the sedimentation capillary, the cuvette having vertical side walls, wherein the cuvette is configured to hold the aqueous sample and the dry sphere simultaneously;   dissolving the dry sphere with the aqueous sample such that the reacting magnetic particles release and sediment to a surface of an integrated circuit;   attracting the magnetic particles to bind on the surface of the integrated circuit using magnetic concentration conductors within the integrated circuit;   quantifying the concentration of the target analyte within the aqueous solution with magnetic particle sensors embedded in the integrated circuit, wherein the magnetic particle sensors are capable of detecting the magnetic particles specifically bound to the surface of the integrated circuit; and   displaying the information of the aqueous solution on a digital display.   
     
     
         10 . The method of  claim 9 , further comprising placing a flow stop above the dry sphere in the cuvette, wherein the flow stop seals the sedimentation capillary when the dry sphere dissolves. 
     
     
         11 . The method of  claim 9 , further comprising a passive unidirectional valve that eliminates and/or reduces the suck-back flow resulting from aqueous sample evaporation through the filter. 
     
     
         12 . The method of  claim 9 , wherein an array of magnetic particle sensors is configured to count the number of specific molecular interactions in a sensing area on the surface of the integrated circuit. 
     
     
         13 . The method of  claim 9 , further comprising providing the sedimentation capillary with a notch that prevents the dry sphere from failing into the sedimentation capillary. 
     
     
         14 . The method of  claim 9 , wherein the cuvette comprises tapered sidewalls, wherein the tapered sidewalls hold the dry sphere in place within the sedimentation capillary. 
     
     
         15 . The method of  claim 9 , further comprising illuminating the surface of the integrated circuit with a plurality of light sources, wherein the plurality of light sources are configured to identify magnetic particles dyed with different colors. 
     
     
         16 . The method of  claim 15 , wherein the magnetic particle sensors comprise optical sensors, wherein the optical sensors are configured to identify the color of a magnetic particle. 
     
     
         17 . An assay system for generating presentable assay information from an aqueous sample, comprising:
 a filter;   a capillary system, wherein the capillary system has a delivery capillary, a surface capillary, and a sedimentation capillary, wherein the delivery capillary, the surface capillary, and the sedimentation capillary are fluidly connected;   a dry sphere containing magnetic particles therein; and   a cuvette extending from the sedimentation capillary, wherein the cuvette has vertical side walls, and wherein the cuvette is configured to hold the dry sphere motionless in place.   
     
     
         18 . The system of  claim 17 , wherein the cuvette comprises tapered sidewalls, wherein the tapered sidewalls are configured to hold the dry sphere in place within the sedimentation capillary. 
     
     
         19 . The system of  claim 17 , wherein the sedimentation capillary comprises a notch, wherein the notch is configured to prevent the dry sphere from falling into the sedimentation capillary. 
     
     
         20 . The system of  claim 17 , wherein the cuvette comprises a flow stop placed above the dry sphere, wherein the flow stop is configured to seal the sedimentation capillary upon dissolution of the dry sphere. 
     
     
         21 . The system of  claim 17 , wherein a passive unidirectional valve is configured to eliminate and/or reduce the suck-back flow resulting from aqueous sample evaporation through the filter.