Micro scale flow through sorbent plate collection device

Abstract

In the invention, a collection device includes a first micro scale plate having a sorbent surface and a through hole. The through hole provides for the passage of an analyte fluid flow through the plate and it has a volume and geometry to provide contact between the fluid and the sorbent surface in an amount effective to absorb a sufficient amount of analyte for subsequent detection of the analyte. The sorbent surface can be provided by a sorbent coating such as an active sensing film, e.g. a conducting or optically active material, examples of which include conducting polymers, polymer/carbon composites, carbon nanotubes. and dye-containing materials. The analyte collection device preferably includes a heating source, e.g. a heating element formed from a resistive trace, or a plurality of resistive traces on or within the first microscale plate, for effecting a thermal release of collected analyte from the plate.

1 . An analyte collection device, the device comprising:
 a first micro scale plate having a sorbent surface: and   a through hole through said first microscale plate. said hole being arranged to permit passage of an analyte fluid flow through said first microscale plate and whereby said hole has a volume and geometry to provide contact between said fluid and said sorbent surface in an amount effective to absorb said analyte thereon in an amount effective for detection.   
     
     
         2 . The analyte collection device of  claim 1 , further comprising a heating source for effecting a thermal release of said collected analyte from said first microscale plate. 
     
     
         3 . The analyte collection device of  claim 2 , wherein said heating source is a heating element comprising a resistive trace formed on or within said first microscale plate. 
     
     
         4 . The analyte collection device of  claim 3 . wherein:
 said heating element comprises a plurality of resistive traces formed on or within said first microscale plate;   wherein said resistive traces divide said microscale plate into a plurality of zones, one of said zones being a collection zone for collecting analyte from environment, and another being a smaller delivery zone for concentrating analyte from the collection zone in a smaller area and delivering analyte to a detector system.   
     
     
         5 . The analyte collection device of  claim 4 , wherein the sorbent surface comprises a sorbent coating that is thicker in said smaller delivery zone than in said collection zone. 
     
     
         6 . The analyte collection device of  claim 1 , further comprising a plurality of through holes through said first microscale plate. 
     
     
         7 . The analyte collection device of  claim 1 , wherein the sorbent surface comprises a sorbent coating on at least a portion of said first microscale plate. 
     
     
         8 . The analyte collection device of  claim 7 , wherein the sorbent coating is an active sensing film selected from the group consisting of conducting and optically active materials. 
     
     
         9 . The analyte collection device of  claim 8 , wherein the sorbent coating is selected from the group consisting of conducting polymers, polymer/carbon composites, carbon nanotubes, and dye-containing materials. 
     
     
         10 . The analyte collection device of  claim 9 , comprising multiple sorbent coatings formed in multiple zones of said first microscale plate, each sorbent coating being selected to sorb a predetermined analyte. 
     
     
         11 . The analyte collection device of  claim 10 , further comprising a heating element for each of said multiple zones. 
     
     
         12 . The analyte collection device of  claim 11 , further comprising a sorbent coating for each of said multiple zones and wherein each said coating comprises a bioreceptor site selected for collecting a desired biorelated analyte. 
     
     
         13 . The analyte collection device of  claim 7 , wherein said device further comprises a means of delivering analyte into one of a capillary gas chromatographic column, a mass spectrometer, and a micro sensor having a pneumatic manifold opening. 
     
     
         14 . The analyte collection device of  claim 1 , further comprising a second micro scale plate with a sorbent surface, a through hole, and heating source, said second microscale plate being arranged downstream of said first micro scale plate such that an analyte fluid flow substantially through said first micro scale plate is also directed through said second microscale plate. 
     
     
         15 . The analyte collection device of  claim 14 , wherein each of said first and second micro scale plates comprises a plurality of through holes. 
     
     
         16 . The analyte collection device of  claim 15 , wherein said through holes through said first micro scale plate are at least partially aligned with solid portions of said second micro scale plate to induce a cascading flow of analyte fluid through said first and second micro scale plates. 
     
     
         17 . The analyte collection device of  claim 16 , further comprising a plurality of microscale plates each having a sorbent surface, a heating source, and a plurality of through holes. 
     
     
         18 . The analyte collection device of  claim 17 , wherein the heating source for each of said microscale plates is a resistive heating trace independently controlled by a microcontroller. 
     
     
         19 . The analyte collection device of  claim 18 . wherein the microcontroller is configured to deliver a pulse width modulation (PWM) signal to each heating trace. 
     
     
         20 . The analyte collection device of  claim 19 , wherein during off pulses of the PWM signal each said heater trace is switched into a measuring circuit that provides a signal proportional to the temperature of the heater trace for regulating the temperature of the heater trace.