High-throughput liquid-absorption preconcentrator sampling methods
OwnerSolomon Zarombinventor
Life of this patent
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Abstract
A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis.
Claims19
A method for preconcentrating an analyte in a gaseous medium comprising the steps of:
- providing a length of wettable material within an inner wall surface of a container,
- wetting one part of the wettable material with an analyte-sorbing liquid so that the liquid moves toward one end of the wettable material for wetting substantially the length thereof,
- flowing the gaseous medium through an inlet opening into the container, over the liquid that is wetting said material in direct contact therewith for trapping and preconcentrating traces of analyte in the sorbing liquid, and collecting from the one end of the wettable material the sorbing liquid containing the preconcentrated traces of analyte,
- limiting any dry surfaces within or connected to said container that the gaseous medium may encounter before contacting the liquid to a negligibly small area, or maintaining the dry surfaces at a temperature at which adsorption of the analyte is negligibly low, and
- detecting said analyte, preconcentrated within said sorbing liquid by an analyte detection means, producing a signal indicative of the presence of said analyte, wherein the volume of sorbing liquid is reduced by allowing the liquid to collect within a portion of the container and to partially evaporate.
A method for preconcentrating an analyte in a gaseous medium comprising the steps of:
- providing a length of wettable material within an inner wall surface of a container,
- wetting one part of the wettable material with an analyte-sorbing liquid so that the liquid moves toward one end of the wettable material for wetting substantially the length thereof,
- flowing the gaseous medium through an inlet opening into the container, over the liquid that is wetting said material in direct contact therewith for trapping and preconcentrating traces of analyte in the sorbing liquid, and collecting from the one end of the wettable material the sorbing liquid containing the preconcentrated traces of analyte,
- limiting any dry surfaces within or connected to said container that the gaseous medium may encounter before contacting the liquid to a negligibly small area, or maintaining the dry surfaces at a temperature at which adsorption of the analyte is negligibly low, and
- detecting said analyte, preconcentrated within said sorbing liquid by an analyte detection means, producing a signal indicative of the presence of said analyte, wherein said temperature is at least 50.degree. C.
A method of collecting liquid or solid particulates from a gaseous medium comprising the steps of:
- providing a cylindrical container with a cylindrical wettable interior wall surface,
- substantially wetting said interior wall surface with a liquid film that is moving toward one end of said container,
- flowing the gaseous medium through an inlet opening into the container over the wetted interior wall surface so that a significant fraction of particulates from the gaseous medium is transferred into the liquid film,
- collecting from the one end of the container a liquid sample that is enriched in said particulates, and,
- detecting said particulates, collected within said liquid sample by a detection means, producing a signal indicative of the presence of said particulates, wherein the volume of the liquid sample is reduced by allowing the liquid sample to collect at the end of the container and to partially evaporate.
A method of collecting an analyte from a gaseous medium comprising the steps of:
- providing a cylindrical container with a cylindrical wettable interior wall surface,
- wetting said interior wall surface with a liquid film that is moving toward one end of said container,
- flowing the gaseous medium through an inlet opening into the container over the wetted interior wall surface in a swirling and highly turbulent motion, so that a significant fraction of the analyte from the gaseous medium is transferred into the liquid film, and
- withdrawing from the one end of the container a liquid sample that is enriched in said analyte, and
- detecting said analyte within said liquid sample by an analyte detection means, producing a signal indicative of the presence of said analyte, wherein the volume of the liquid sample is reduced by allowing the liquid sample to collect within a portion of the container and to partially evaporate.
Dependencies are inferred from the claim text.