Matching thermally modulated variable restrictors to chromatography separation columns

Patent metadata

Field	Value
Publication number	US-2020333301-A1
Application number	US-202016917178-A
Country	US
Kind code	A1
Filing date	Jun 30, 2020
Priority date	Mar 12, 2013
Publication date	Oct 22, 2020
Grant date	—

Abstract

Thermally modulated variable restrictors used in chromatography systems enable independent control of system pressure and linear velocity of a compressible mobile phase passing through a chromatography column. A method for configuring a chromatography system with independent control of system pressure and mass flow rate of a compressible mobile phase includes determining a type of chromatography separation column to be used in the chromatography system, matching a thermally modulated variable restrictor to the type of chromatography separation column for use together during operation of the chromatography system, and bundling the chromatography column with its matching thermally modulated variable restrictor for distribution as a single package.

First claim

What is claimed is:

1 . A method for configuring a chromatography system with independent control of system pressure and mass flow rate of a compressible mobile phase, comprising:
determining a type of chromatography separation column to be used in the chromatography system; matching a thermally modulated variable restrictor to the type of chromatography separation column for use together during operation of the chromatography system; and bundling the chromatography separation column with the thermally modulated variable restrictor for distribution together as a single unit.

2 . The method of claim 1 , wherein the matching of a thermally modulated variable restrictor to the type of chromatography separation column is based on a mass flow rate of the compressible mobile phase through the chromatography separation column during operation of the chromatography system.

3 . The method of claim 1 , wherein each different type of chromatographic separation column is bundled with a matching thermally modulated variable restrictor of a different temperature-pressure characteristic.

4 . The method of claim 1 , wherein the matching of a thermally modulated variable restrictor to the type of chromatography separation column includes determining a temperature range over which to operate the thermally modulated variable restrictor in order to regulate system pressure.

5 . The method of claim 1 , wherein the matching of a thermally modulated variable restrictor to the type of chromatographic separation column includes determining a length of the thermally modulated variable restrictor to be heated.

6 . The method of claim 1 , wherein the matching of a thermally modulated variable restrictor to the type of chromatography separation column includes determining a size of an internal diameter of the thermally modulated variable restrictor.

7 . The method of claim 1 , wherein the thermally modulated variable restrictor that is matched to the type of chromatography separation column achieves a constant linear velocity of mobile phase through the chromatography separation column during operation of the chromatography system.

8 . A method comprising:
configuring a chromatography system by matching a type of chromatography separation column to be used in a chromatography system with a thermally modulated variable restrictor to achieve a desired performance of the chromatography system.

9 . The method of claim 8 , wherein the desired performance is selected from the group consisting of: a desired mass flow rate of a compressible mobile phase through the chromatography separation column, a constant linear velocity of a compressible mobile phase through the chromatography separations column, a control of over the compressible mobile phase flow rate, a target system pressure, and a combination thereof.

10 . The method of claim 8 , wherein the thermally modulated variable restrictor is constructed to match the chromatography separation column by varying structural features of the thermally modulated variable restrictor, including at least one of: a size of an opening of the thermally modulated variable restrictor, a length of the thermally modulated variable restrictor to be heated, and a size of an internal diameter of the thermally modulated variable restrictor.

11 . The method of claim 8 , wherein the restrictor is a thermally modulated variable restrictor comprising:
a restrictor body having a fluidic channel with an inlet end that receives a compressible mobile phase from the chromatography separation column and an outlet end through which the mobile phase leaves the fluidic channel; a restrictor tip disposed adjacent the restrictor body at the outlet end of the fluidic channel, the restrictor tip having an egress opening that is smaller than an internal diameter of the fluidic channel; and a heating element thermally coupled to a subsection of the fluidic channel between the inlet and outlet ends to heat the compressible mobile phase passing through that subsection of the fluidic channel.

12 . A method comprising:
configuring a chromatography system by matching a chromatography separation column to be used in the chromatography system with a thermally modulated variable restrictor, the thermally modulated restrictor comprising: a restrictor body having a fluidic channel with an inlet end that is configured to receive a compressible mobile phase from the chromatography separation column, and an outlet end through which the compressible mobile phase leaves the fluidic channel, a restrictor tip having an inlet end disposed adjacent to an outlet end of the restrictor body, the restrictor tip having an egress opening that is smaller than an internal diameter of the fluidic channel, wherein the restrictor tip is unheated, and a heating element thermally coupled to a subsection of the fluidic channel between the inlet end and the outlet end to heat the compressible mobile phase passing through that subsection of the fluidic channel, the heating element directly contacting an outer surface of the restrictor body, and extending along the subsection of the fluidic channel and ending prior to reaching the inlet end of the restrictor tip.

13 . The method of claim 8 , wherein the restrictor body comprises tubing to provide the fluidic channel, and wherein the heating element includes a wire coiled around the tubing.

14 . The method of claim 8 , wherein the restrictor body comprises a microfluidic substrate within which the fluidic channel is formed.

15 . The method of claim 8 , wherein the desired performance is selected from the group consisting of: a desired mass flow rate of a compressible mobile phase through the chromatography separation column, a constant linear velocity of the compressible mobile phase through the chromatography separation column, a control of over a compressible mobile phase flow rate, a target system pressure, and a combination thereof.

Assignees

• Waters Technologies Corp

Inventors

• Fogwill Michael O
• Michienzi Joseph D
• Gerhardt Geoff
• Murphy James P

Classifications

• G01N30/8658

  Optimising operation parameters · CPC title

• B01D15/08

  Selective adsorption, e.g. chromatography · CPC title

• B01D15/163

  Pressure or speed conditioning · CPC title

• G01N2030/025

  Gas chromatography · CPC title

• B01D15/161

  Temperature conditioning · CPC title