Portable micro-preconcentrator to facilitate chemical sampling and subsequent analysis

Patent metadata

Field	Value
Publication number	US-10940428-B2
Application number	US-201716087054-A
Country	US
Kind code	B2
Filing date	Mar 23, 2017
Priority date	Mar 25, 2016
Publication date	Mar 9, 2021
Grant date	Mar 9, 2021

Abstract

The disclosed embodiments relate to the design of a preconcentrator system for preconcentrating air samples. This preconcentrator system includes a plurality of preconcentrators that preconcentrate the air samples prior to chemical analysis, and a delivery structure comprising a manifold that selectively routes a sample airflow to the plurality of concentrators so that the plurality of preconcentrators receive a sample airflow concurrently or individually.

First claim

What is claimed is:

1. A preconcentrator for preconcentrating gas samples for agricultural applications, comprising:
multiple preconcentrators that are programmable to separately sample during different time slots, each preconcentrator including a substrate that comprises:
one or more channels for accommodating a sample flow, wherein the one or more channels are coated with a sorbent material so that the sorbent material can be exposed to the sample flow; and
one or more heaters for heating the sorbent material.

2. The preconcentrator of claim 1 , wherein the sample flow includes one or more of:
gas samples outgassed from plants in a greenhouse;
gas samples outgassed from plants in an orchard;
gas samples obtained during post-harvest transportation of agricultural products; and
gas samples obtained during post-harvest storage of agricultural products.

3. The preconcentrator of claim 1 , further comprising a pump that facilitates moving the sample flow through the sorbent material.

4. The preconcentrator of claim 1 , wherein a sorbent type and a sampling temperature are controllable during sampling to promote capture of volatile organic compounds of interest over extraneous chemicals.

5. The preconcentrator of claim 1 , further comprising an external cooling supply.

6. The preconcentrator of claim 1 , wherein the one or more heaters trigger a release of absorbed compounds from the sorbent material.

7. The preconcentrator of claim 1 , wherein the one or more heaters are fabricated by depositing a conductive material on the substrate.

8. The preconcentrator of claim 1 , wherein the one or more heaters uniformly heat an active area.

9. The preconcentrator of claim 1 , further comprising:
one or more temperature sensors; and
a feedback-based temperature control system that uses readings from the one or more temperature sensors to control the one or more heaters.

10. The preconcentrator of claim 1 , wherein the one or more channels comprise high-aspect-ratio, porous microstructures for holding the sorbent material.

11. The preconcentrator of claim 10 , wherein the high-aspect-ratio microstructures include channels that are about 300 micrometers tall and 10 micrometers wide.

12. The preconcentrator of claim 1 , wherein the one or more heaters are programmable to do one or more of the following:
apply heat rapidly to instantly desorb chemicals from the sorbent material; and
apply heat gradually to control a release of different compounds at different times from the sorbent material.

13. The preconcentrator of claim 1 , wherein the preconcentrator is fabricated using photolithography techniques.

14. The preconcentrator of claim 13 , wherein the preconcentrator is fabricated using anisotropic wet-etch techniques.

15. The preconcentrator of claim 1 , further comprising:
a sampler cartridge system comprising multiple sample cartridges, wherein:
each said sample cartridge houses one of the multiple preconcentrators; and
no more than one cartridge at a time is positioned within the sample flow.

16. A preconcentrator for preconcentrating gas samples for agricultural applications, comprising:
at least one substrate, each substrate including:
one or more channels for accommodating a sample flow, wherein the one or more channels are coated with a sorbent material so that the sorbent material can be exposed to the sample flow; and
one or more heaters for heating the sorbent material;

an aerial platform capable of flight, wherein the aerial platform includes an airfoil; and
an air intake, located in a field of air flow across the airfoil during flight of the aerial platform, for creating the sample flow.

17. The preconcentrator of claim 16 , further comprising:
a cartridge system comprising multiple cartridges, wherein:
each said cartridge houses one of the at least one substrate; and
no more than one cartridge at a time is positioned within the sample flow.

18. The preconcentrator of claim 17 , further comprising:
a memory that stores a geolocation and a time at which each cartridge is exposed to the sample flow.

19. The preconcentrator of claim 16 , further comprising:
an array of samplers, each sampler including one of the multiple preconcentrators; and
one or both of a solenoid and a manifold for directing the sample flow to no more than one of the samplers at a time.

Assignees

• Univ California

Inventors

• Davis Cristina E
• Levasseur Michael K
• Cumeras Raquel
• Zrodnikov Yuriy
• Mccartney Mitchell M
• Fung Alexander G
• Peirano Daniel J

Classifications

• A61B5/082

  Evaluation by breath analysis, e.g. determination of the chemical composition of exhaled breath (A61B5/083, A61B5/091 take precedence) · CPC title

• G01N33/497

  of gaseous biological material, e.g. breath · CPC title

• G05D27/00

  Simultaneous control of variables covered by two or more of main groups G05D1/00 - G05D25/00 · CPC title

• G05D23/00

  Control of temperature · CPC title

• G05D22/00

  Control of humidity · CPC title