Sample injection with fluidic connection between fluid drive unit and sample accommodation volume

• US 10,641,746 B2
• Filed: 05/30/2017
• Issued: 05/05/2020
• Est. Priority Date: 05/30/2016
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Thielsch, Daniel, Ortmann, Thomas
• Primary Examiner(s): Gibson, Randy W
• Assistant Examiner(s): Kidanu, Gedeon M
• Application Number:
  US15/608,903
• Publication Number:
  US 20170343518A1
• Time in Patent Office: 1,071 Days
• CPC Class Codes: F16K 11/074 with flat sealing faces
• CPC Class Codes: G01N 2030/201 multiport valves, i.e. having more than two ports
• CPC Class Codes: G01N 2030/202 rotary valves
• CPC Class Codes: G01N 2030/207 with metering cavity, e.g. sample loop
• CPC Class Codes: G01N 30/06 Preparation
• CPC Class Codes: G01N 30/20 using a sampling valve
• CPC Class Codes: G01N 30/22 in high pressure liquid systems
• CPC Class Codes: G01N 30/32 of pressure or speed G01N30/36 takes precedence

Abstract

An injector, for injecting a fluidic sample into a flow path between a fluid drive and a sample separation unit, includes a sample accommodation volume, a sample drive, and a fluidic valve switchable to selectively couple the volume with the flow path or decouple the volume from the flow path. In an injection switching state, the fluid drive, the separation unit and the sample drive are coupled by the valve so that fluid driven by the sample drive and flowing from the volume to the separation unit and further fluid driven by the fluid drive and flowing from the fluid drive to the separation unit are combined at a fluidic connection upstream of the separation unit. A control unit controls a pressure of the fluid and/or the further fluid during injecting.

Claims

1. An injector for injecting a fluidic sample into a main flow path between a fluid drive and a separation unit of a sample separation apparatus, the injector comprising:

a sample accommodation volume configured to accommodate the fluidic sample prior to injecting;

a sample drive configured to intake the fluidic sample into the sample accommodation volume, and to drive the intaken fluidic sample along a metering flow path from the sample accommodation volume to the main flow path;

a fluidic valve switchable between multiple switching states to thereby selectively couple the sample accommodation volume with the main flow path or decouple the sample accommodation volume from the main flow path, wherein in an injection switching state of the fluidic valve, the fluid drive, the separation unit and the sample drive are fluidically coupled by the fluidic valve so that the intaken fluidic sample, driven by the sample drive and flowing from the sample accommodation volume to the separation unit along the metering flow path, and further fluid driven by the fluid drive and flowing from the fluid drive to the separation unit along the main path are combined at a fluidic connection upstream of the separation unit; and

a control unit configured to control a pressure during injecting the fluidic sample from the sample accommodation volume into the main flow path, the pressure selected from the group consisting of;

the pressure of the intaken fluidic sample driven by the sample drive;

the pressure of the further fluid driven by the fluid drive; and

the pressure of the combined fluid as the combination of the intaken fluidic sample driven by the sample drive and the further fluid driven by the fluid drive.

2. The injector according to claim 1, wherein the control unit is configured to control the pressure at the fluidic connection during injection.

3. The injector according to claim 1, wherein the control unit is configured to synchronize operation of the fluid drive and the sample drive for controlling the pressure.

4. The injector according to claim 1, wherein the further fluid driven by the fluid drive comprises a mobile phase, and the control unit is configured to adjust a mixing ratio between the mobile phase and the fluidic sample at the fluidic connection.

5. The injector according to claim 1, wherein the control unit is configured to adjust at least one of a predefined total pressure value and a predefined outlet flow rate value according to which a mixture or combination between mobile phase and fluidic sample is driven through the separation unit.

6. The injector according to claim 1, wherein the fluidic valve is configured to be switchable in another injection switching state in which the fluidic sample is injected towards the separation unit driven by the fluid drive while the sample accommodation volume is located downstream of the fluid drive and upstream of the separation unit.

7. The injector according to claim 1, comprising at least one of the following features:

wherein the sample drive is configured to intake an amount of fluidic sample into the sample accommodation volume and to subsequently inject multiple portions of the intaken amount of fluidic sample towards the separation unit, which portions are to be separated spaced by one or more predefined delay times;

wherein the fluidic valve comprises a stator and a rotor being rotatable relative to one another, wherein the fluidic valve comprises one of the following features;

the stator comprises a plurality of ports and at least one fluid conduit in permanent fluid communication with at least part of the plurality of ports, and the rotor comprises at least one fluid conduit;

the stator comprises a plurality of ports but no fluid conduits, and the rotor comprises at least one fluid conduit.

8. The injector according to claim 1, wherein the fluid drive and the sample drive are controllable for injecting a predefined fluidic sample-mobile phase mixture by mixing, at the fluidic connection, the fluidic sample driven by the sample drive and a mobile phase driven by the fluid drive with a predefined mixing ratio.

9. The injector according to claim 8, configured to adjust the mixing ratio by adjusting a volume-over-time displacement characteristic by which the sample drive drives the fluidic sample.

10. The injector according to claim 1, wherein the sample drive is operable and the fluidic valve is switchable into a pressure adjustment switching state in which a predefined overpressure for injection is adjustable in the sample accommodation volume before switching the fluidic valve for injecting the fluidic sample towards the separation unit.

11. The injector according to claim 10, wherein the sample drive is operable and the fluidic valve is switchable so that the predefined overpressure for injection triggers injection of the fluidic sample from the sample accommodation volume towards the separation unit by pressure equilibration, without piston motion and/or exclusively by pressure equilibration.

12. A sample separation apparatus for separating a fluidic sample, the sample separation apparatus comprising:

the injector according to claim 1;

the fluid drive configured to drive a mobile phase; and

the separation unit configured to separate the fluidic sample in the mobile phase;

wherein the further fluid driven by the fluid drive comprises the mobile phase.

13. The sample separation apparatus of claim 12, further comprising at least one of the following features:

the detector configured to detect separated fractions of the fluidic sample;

the fractionating unit configured to collect separated fractions of the fluidic sample;

a degassing apparatus configured to degas the mobile phase;

the sample separation apparatus is configured as a chromatography sample separation apparatus.

14. An injector for injecting a fluidic sample into a main flow path between a fluid drive and a separation unit of a sample separation apparatus, the injector comprising:

a sample accommodation volume configured to accommodate the fluidic sample prior to injecting;

a sample drive configured to intake the fluidic sample into the sample accommodation volume, and to drive the intaken fluidic sample along a metering flow path from the sample accommodation volume to the main flow path;

a fluidic valve switchable between multiple switching states to thereby selectively couple the sample accommodation volume with the main flow path or decouple the sample accommodation volume from the main flow path, wherein in an injection switching state of the fluidic valve, the fluid drive, the separation unit and the sample drive are fluidically coupled at a fluidic coupling point defined by a port of the fluidic valve so that the intaken fluidic sample driven by the sample drive and flowing from the sample accommodation volume to the separation unit and along the metering flow path, further fluid driven by the fluid drive and flowing from the fluid drive to the separation unit along the main flow path, are combined at the fluidic coupling point upstream of the separation unit; and

a control unit configured to control a pressure during injecting the fluidic sample from the sample accommodation volume into the main flow path, the pressure selected from the group consisting of;

the pressure of the intaken fluidic sample driven by the sample drive;

the pressure of the further fluid driven by the fluid drive; and

the pressure of the combined fluid as the combination of the intaken fluidic sample driven by the sample drive and the further fluid driven by the fluid drive.

15. The injector according to claim 14, wherein the fluidic coupling point is located in an interior of the fluidic valve.

16. The injector according to claim 14, wherein the fluidic valve is a rotatable fluidic valve having a rotor and a stator being rotatable relative to one another so as to bring different fluid ports of the stator in alignment with at least one respective fluidic conduit in the rotor.

17. The injector according to claim 16, wherein the fluidic coupling point is at least partially defined by one fluid port being fluidically coupled to one fluid conduit at a central position of this fluid conduit in the injection switching state, wherein the fluid port is further fluidically connected to a capillary guiding towards the separation unit.

18. A method of injecting a fluidic sample into a flow path between a fluid drive and a separation unit of a sample separation apparatus, the method comprising:

intaking fluidic sample in a sample accommodation volume of an injector by a sample drive;

switching a fluidic valve of the injector into an injection switching state in which the fluidic valve fluidically couples the fluid drive, the sample drive and the separation unit so that the intaken fluidic sample driven by the sample drive and flowing from the sample accommodation volume to the separation unit and further fluid driven by the fluid drive and flowing from the fluid drive to the separation unit are combined at a fluidic connection upstream of the separation unit to thereby inject the fluidic sample from the sample accommodation volume in the flow path in the injection switching state; and

controlling a pressure during the injecting, the pressure selected from the group consisting of;

the pressure of the intaken fluidic sample driven by the sample drive;

the pressure of the further fluid driven by the fluid drive; and

the pressure of the combined fluid as the combination of the intaken fluidic sample driven by the sample drive and the further fluid driven by the fluid drive.

19. The method according to claim 18, wherein the fluidic connection comprises a fluidic coupling point defined by a port of the fluidic valve.

20. The method according to claim 18, comprising switching the fluidic valve in another injection switching state in which fluidic sample is injected towards the separation unit driven by the fluid drive while the sample accommodation volume is located downstream of the fluid drive and upstream of the separation unit.