Method and apparatus for comprehensive two-dimensional gas chromatography
AssigneeOakland University
InventorJohn V. Seeley
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Abstract
A two-dimensional gas chromatograph with a primary column (14) and dual secondary columns (26, 28) is described. Flow rates in the primary column are less than those in the secondary columns due to an accumulation valve (16). Typically the ratio of second and third column flow capacities combined to primary column flow capacities between about 10 to 1 and 30 to 1. Volatile organic compounds are detected in environmental samples of air water, soil and in body fluids of animals and humans.
Claims12
A method for comprehensive two-dimensional gas chromatography comprising the steps of;
- injecting a sample into a primary column to obtain a first dimension;
- communicating said sample from said primary column through a valve which accumulates the sample;
- injecting at least a portion of said accumulated sample from said valve through a single connection to the valve simultaneously into a first and a second secondary column to obtain pair of second dimensions and wherein the first secondary column has a selectivity different from the second secondary column.
A comprehensive two-dimensional gas chromatograph apparatus, said apparatus comprising:
- a primary column, said primary column interacting with a sample to provide a first dimension result;
- a first secondary column and a second secondary column, said sample interacting with each of said first and second secondary columns to provide a pair of second dimension results;
- and
- a valve, said valve providing fluid communication of said sample from said primary column simultaneously to each said first and second secondary columns by accumulation of the sample in the valve and then transfer into the secondary columns, whereby said secondary columns are in a parallel arrangement through a single connection to the valve and wherein the first secondary column has a selectivity different from the second secondary column.
A comprehensive two-dimensional gas chromatograph apparatus, said apparatus comprising:
- a primary non-polar column, said primary column interacting with sample to provide a first dimension result;
- a first polar secondary column and a second polar secondary column, said sample interacting with each of said first and second secondary columns to provide a pair of second dimension results;
- and
- a valve, said valve providing fluid communication of said sample from said primary column to each said first and second secondary columns by accumulation of the sample in the valve and simultaneous periodic injection from the valve into the secondary columns, whereby said secondary columns are in a parallel arrangement through a single connection to the valve and wherein the first secondary column has a selectivity different from the second secondary column.
Dependencies are inferred from the claim text.