Automated sample concentrator for trace components

Claim 3

Apparatus for concentrating the solutes contained in a liquid solvent other than supercritical fluid before they are applied to chromatographic apparatus for analysis, comprising: a first trapping means containing material for adsorbing and accumulating at least some solutes from said liquid solvent other than supercritical fluid passing through it, means for causing the liquid solvent, when present, to flow through said first trapping means and out to waste, second trapping means, means for changing a liquid-gas combination into supercritical fluid and to cause said supercritical fluid to flow through said first trapping means and into said second trapping means, said means for changing a liquid-gas combination into supercritical fluid being operative when a source of liquid-gas is coupled thereto, said second trapping means being such as to reduce the density of any supercritical fluid entering it so as to reduce its solubility parameter and thus retain at least some of the solutes.

Claim 4

Apparatus for concentrating the solutes contained in a liquid solvent other than supercritical fluid before they are applied to chromatographic apparatus for analysis, comprising: a first trapping means containing material for adsorbing and accumulating at least some solutes from said liquid solvent other than supercritical fluid passing through it, means for causing the liquid solvent, when present, to flow through said first trapping means and out to waste, second trapping means, means for changing a liquid-gas combination into supercritical fluid and to cause said supercritical fluid to flow through said first trapping means and into said second trapping means, said means for changing a liquid-gas combination into supercritical fluid being operative when a source of liquid-gas is coupled thereto, said second trapping means being such as to reduce the density of any supercritical fluid entering it so as to reduce its solubility parameter and thus retain at least some of the solutes.

Claim 5

Apparatus as set forth in claim 2 wherein said first trapping means is of the reverse phase type.

Claim 6

Apparatus as set forth in claim 3 wherein said second trapping means contains polyphenoxy ether material.

Claim 7

Apparatus as set forth in claim 2 wherein said first trapping means is of the normal phase type.

Claim 8

Apparatus as set forth in claim 5 wherein said second trapping means contains polyphenoxy ether material.

Claim 9

Apparatus as set forth in claim 2 wherein said first trapping means and said second trapping means contain material of the reverse bonded phase type.

Claim 10

Apparatus as set forth in claim 2 wherein said first trapping means and said second contain material of the normal phase type.

Claim 11

Apparatus as set forth in claim 2 wherein said first trapping means contains silica.

Claim 12

Apparatus as set forth in claim 2 wherein said first trapping means contains alumina.

Claim 13

Apparatus as set forth in claim 2 wherein said first trapping means contains charcoal.

Claim 14

Apparatus for concentrating solutes contained in a liquid solvent other than supercritical fluid and conveying them to chromatographic detection means, comprising: trapping means for adsorbing and accumulating solutes from the liquid solvent when it passes therethrough, means for causing the liquid solvent, when present, to pass through said trapping means and out to waste, supercritical fluid chromatographic apparatus having a separation column, and means for causing supercritical fluid to pass through said trapping means and to the separation column of said chromatographic apparatus after the solutes have been accumulated in said trapping means.

Claim 15

Apparatus for concentrating solutes contained in a liquid solvent other than supercritical fluid and conveying them to chromatographic detection means, comprising: trapping means for adsorbing and accumulating solutes from the liquid solvent when it passes therethrough, means for causing the liquid solvent, when present, to pass through said trapping means and out to waste, supercritical fluid chromatographic apparatus having a separation column, and means for causing supercritical fluid to pass through said trapping means and to the separation column of said chromatographic apparatus after the solutes have been accumulated in said trapping means.

Claim 16

In a chromatographic system, a method for deriving an amount of a solute that is above the minimum detectable level for the detector involved from a solvent other than a supercritical fluid in which the amount of solute contained in the largest sample volume of the solvent that can be injected is less than the minimum detectable level for the detector, the said method comprising: passing solvent through a first trapping means until the amount of solute accumulated therein is greater than the minimum detectable level, passing supercritical fluid through said first trapping means so as to adsorb at least a portion of the solute and then into a second trapping means, and reducing the solubility parameter of the supercritical fluid in said second trapping means so that an amount of the solute at least equal to the minimum detectable level is left in the second trapping means.

Claim 17

In a chromatographic system, a method for deriving an amount of a solute that is above the minimum detectable level for the detector involved from a solvent other than a supercritical fluid in which the amount of solute contained in the largest sample volume of the solvent that can be injected is less than the minimum detectable level for the detector, the said method comprising: passing solvent through a first trapping means until the amount of solute accumulated therein is greater than the minimum detectable level, passing supercritical fluid through said first trapping means so as to adsorb at least a portion of the solute and then into a second trapping means, and reducing the solubility parameter of the supercritical fluid in said second trapping means so that an amount of the solute at least equal to the minimum detectable level is left in the second trapping means.

Claim 18

Apparatus for deriving an amount of solute that is above a given minimum detectable level for a given detector from a solvent in which the amount of solute contained in the largest sample volume of the solvent that can be used is less than the minimum detectable level for the detector, the said apparatus comprising: a first trapping means, means for causing solvent to pass through said first trapping means until the amount of solute contained therein exceeds the minimum detectable level, a second trapping means, a source of supercritical fluid and means for causing it to pass through said first trapping means and into said second trapping means, said second trapping means being such as to reduce the density of supercritical fluid entering it so as to reduce its solubility parameter.

Claim 19

Apparatus for deriving an amount of solute that is above a given minimum detectable level for a given detector from a solvent in which the amount of solute contained in the largest sample volume of the solvent that can be used is less than the minimum detectable level for the detector, the said apparatus comprising: a first trapping means, means for causing solvent to pass through said first trapping means until the amount of solute contained therein exceeds the minimum detectable level, a second trapping means, a source of supercritical fluid and means for causing it to pass through said first trapping means and into said second trapping means, said second trapping means being such as to reduce the density of supercritical fluid entering it so as to reduce its solubility parameter.

Claim 20

Apparatus as set forth in claim 14 wherein said first trapping means is of the reverse phase type.

Claim 21

Apparatus as set forth in claim 15 wherein said second trapping means contains polyphenoxy ether material.

Claim 22

Apparatus as set forth in claim 14 wherein said first trapping means is of the normal phase type.

Claim 23

Apparatus as set forth in claim 17 wherein said second trapping means contains polyphenoxy ether material.

Claim 24

Apparatus as set forth in claim 14 wherein said first trapping means and said second trapping means contain material of the reverse bonded phase type.

Claim 25

Apparatus as set forth in claim 14 wherein said first trapping means and said second trapping means contain material of the normal phase type.

Claim 26

Apparatus as set forth in claim 14 wherein said first trapping means contains silica.

Claim 27

Apparatus as set forth in claim 14 wherein said first trapping means contains alumina.

Claim 28

Apparatus as set forth in claim 14 wherein said first trapping means contains charcoal.

Claim 29

Apparatus as set forth in claim 14 wherein said first trapping means is an HPLC column and said second trapping means contains polyphenoxyether polymer.