Systems and methods for refractive index detection

Patent metadata

Field	Value
Publication number	US-11268902-B2
Application number	US-201815953276-A
Country	US
Kind code	B2
Filing date	Apr 13, 2018
Priority date	Mar 15, 2013
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

The invention provides differential refractive index detectors and methods for the use of differential refractive index detectors. In an exemplary embodiment, a differential refractive index detector includes a flow cell body having a proximal end, a distal end, and a flow axis extending between the proximal and the distal end. The flow cell body includes a first chamber and a second chamber and the fluid conduits coupled to the flow cell body can be tapered to reduce dispersion.

First claim

What is claimed is:

1. A differential refractive index detector, comprising:
a flow cell body having a proximal end, a distal end and a flow axis extending between the proximal end and the distal end, the flow cell body comprising a flow cell assembly having discrete optically transmissive elements and comprising:
a first assembly including a sample chamber having a cross-sectional profile that includes at least a curved portion and is configured to permit a sample flow in a direction parallel to the flow axis; and
a second assembly including a reference chamber to receive a reference liquid, the reference chamber having a cross-sectional profile that is different from the cross-sectional profile of the sample chamber,

wherein the first assembly and the second assembly are joined, and the discrete optically transmissive elements provide for passage of an optical beam which interrogates a refractive index of the sample flow and a reference liquid in a direction perpendicular to the flow axis.

2. The differential refractive index detector of claim 1 , wherein at least one of the sample chamber and the reference chamber is formed by at least one of a circular bore and an elliptical bore provided through a long axis of the flow cell body.

3. The differential refractive index detector of claim 1 , further comprising:
a first window fluidically separating the sample chamber from the reference chamber.

4. The differential refractive index detector of claim 3 , further comprising:
a second window preventing fluidic leakage from the sample chamber outside of the flow cell body.

5. The differential refractive index detector of claim 4 , further comprising:
a third window preventing fluidic leakage from the reference chamber outside of the flow cell body.

6. The differential refractive index detector of claim 5 , wherein the third window is sealed to the reference chamber by at least one of an edge seal and a gasket interposed between the third window and a receiving surface.

7. The differential refractive index detector of claim 4 , wherein the second window is sealed to the sample chamber by at least one of an edge seal and a gasket interposed between the second window and a receiving surface.

8. The differential refractive index detector of claim 5 , wherein at least one of:
the second window is received in a cavity of the first assembly including the sample chamber; and
the third window is received in a cavity of the second assembly including the reference chamber.

9. The differential refractive index detector of claim 1 , wherein the first assembly including the sample chamber and the second assembly including the reference chamber are joined by at least one of: a fastener; a screw; and a clamp.

10. The differential refractive index detector of claim 1 , further comprising
a main joint joining the first assembly including the sample chamber and the second assembly including the reference chamber, the main joint including an O-ring seal and a corresponding groove.

11. The differential refractive index detector of claim 1 , further comprising:
at least one counterbore accommodating at least one of a clamp and a retaining mechanism to maintain at least one of a first window and a second window in a recess of at least one of the first assembly and the second assembly.

12. The differential refractive index detector of claim 1 , wherein sharp corners have been eliminated from at least one of the sample chamber and the reference chamber.

13. The differential refractive index detector of claim 1 , wherein a volume of at least one of the sample chamber and the reference chamber is at least one of: less than or equal to about 5 uL; in a range of about 2 uL to 5 uL; and less than or equal to about 2 uL.

14. The differential refractive index detector of claim 1 , wherein the at least a curved portion comprises at least a portion of a circle.

15. The differential refractive index detector of claim 1 , wherein the at least a curved portion comprises at least a portion of an ellipse.

16. A differential refractive index detector, comprising:
a flow cell body having a proximal end, a distal end and a flow axis extending between the proximal and the distal end, the flow cell body comprising a flow cell assembly having discrete optically transmissive elements and including:
a sample chamber;
a first connector having a tapered connector bore and being in fluid communication with the sample chamber;
a reference chamber;
a second connector having a tapered connector bore and being in communication with the reference chamber;
a first window fluidically separating the sample chamber from the reference chamber;
a second window preventing fluidic leakage from the sample chamber outside of the flow cell body; and
a third window preventing fluidic leakage from the reference chamber outside of the flow cell body;

the flow cell assembly comprising:
a first assembly including the sample chamber and second window, the first assembly configured to permit a sample flow in a direction parallel to the flow axis;
a second assembly including the reference chamber and the third window, the second assembly configured to permit a reference flow in a direction parallel to the flow axis;

wherein the first assembly and the second assembly are joined by a fastener and a cross-sectional profile of the sample chamber taken perpendicular to the flow axis includes at least one curved portion, the reference chamber having a cross-sectional profile that is different from the cross-sectional profile of the sample chamber, and the discrete optically transmissive elements provide for passage of an optical beam which interrogates a refractive index of the sample flow and a reference liquid in a direction perpendicular to the flow axis.

Assignees

• Waters Technologies Corp

Inventors

• Jeannotte Anthony C
• Basile Mark
• Bala Senthil
• Fredette Colin

Classifications

• G01N21/05 Primary

  Flow-through cuvettes (G01N21/09 takes precedence; handling fluid samples G01N1/10) · CPC title

• G01N21/4133 Primary

  Refractometers, e.g. differential · CPC title

• G01N2021/4146

  Differential cell arrangements · CPC title

• G01N30/74

  Optical detectors {(measurement of intensity, velocity, spectral content, polarisation, or phase of infrared, visible or ultraviolet light G01J)} · CPC title