US3830369A - High pressure gradient chamber for liquid chromatography - Google Patents

High pressure gradient chamber for liquid chromatography Download PDF

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US3830369A
US3830369A US00423794A US42379473A US3830369A US 3830369 A US3830369 A US 3830369A US 00423794 A US00423794 A US 00423794A US 42379473 A US42379473 A US 42379473A US 3830369 A US3830369 A US 3830369A
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chamber
cap
set forth
recess
passage
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US00423794A
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E Pfadenhauer
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/34—Control of physical parameters of the fluid carrier of fluid composition, e.g. gradient
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/04—Preparation or injection of sample to be analysed
    • G01N30/16—Injection
    • G01N30/22—Injection in high pressure liquid systems
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/34—Control of physical parameters of the fluid carrier of fluid composition, e.g. gradient
    • G01N2030/347—Control of physical parameters of the fluid carrier of fluid composition, e.g. gradient mixers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/50—Conditioning of the sorbent material or stationary liquid
    • G01N30/56—Packing methods or coating methods
    • G01N2030/562—Packing methods or coating methods packing
    • G01N2030/565—Packing methods or coating methods packing slurry packing

Definitions

  • the present invention is concerned with a simple, efficient gradient device which can be produced at a fraction of the cost of known devices and which permits accurate mixing for a precise gradient without introducing voids which would interfere with subsequent detection in the chromatographic column.
  • This is accomplished by combining an element having a chamber therein and a cap device.
  • the cap is provided with a suitable passage to direct a solvent under high pressure into the chamber to be mixed by a magnetic stirrer with an eluant within the chamber, the pressure forcing the mix from the chamber through a second passage in the cap to the liquid column where the analysis is made.
  • FIG. 1 is a top plan view of a high pressure gradient chamber according to the invention.
  • FIG. 2 is a view partially in section taken along line 2-2 of FIG. 1;
  • FIG. 3 is a view in section taken along lines 3-3 of FIG. 2.
  • cap 10 the basic components of the device are a cap 10, element 12, retainer 14, stem 16, and magnetic stirring bar 18.
  • element 12 the basic components of the device are a cap 10, element 12, retainer 14, stem 16, and magnetic stirring bar 18.
  • FIGS. 2 and 3 the basic components of the device are a cap 10, element 12, retainer 14, stem 16, and magnetic stirring bar 18. The structural details of these elements can most clearly be seen in FIGS. 2 and 3.
  • Cap is a generally cylindrical element.
  • a cylindrical recess is provided at one end of the cap, this recess being threaded along a portion of its length as indi- 'cated at 22.
  • a pair of passages are machined in the cap,
  • passages communicating with the recess 20.
  • One of these passages is designated as an inlet passage 24, while the other passage 26 serves as an outlet.
  • the ends of passages 24 and 26 remote from the recess 20 communicate with internally threaded cavities 28 and 30 which receive conventional fittings 32 and 34, respectively.
  • Fitting 32 is associated with a conduit 36 which is joined to a source of solvent moved under high pressure by a pump (not shown), while fitting 34 couples the outlet passage 26 to a liquid chromatographic column (not shown) via conduit 38.
  • Element 12 is generally cylindrical and has an annular flange portion 40 at one end thereof.
  • the external diameter of the flange is slightly less than the diameter of the recess 20 in cap 10. Consequently, element 12 is received within recess 20 as shown.
  • retainer 14 is employed.
  • This retainer IS an annularly shaped device having external threads which cooperate with threads 22 within recess 20.
  • the diameter of the passage through retainer 14 substantially corresponds to the diameter of the cylindrical portion of element 12. Consequently, retainer 14 is slipped over the end of element 12 and is screwed into recess 20 so as to engage the shoulders of the element which are defined by flange 40. Thus, element 12 is held in position within the recess 20 of cap 10.
  • the retainer 14 is provided with recesses 42 in one face thereof, these recesses serving to accept a suitable tool for tightening the threaded retainer, and thus the element 12 within recess 20.
  • Element 12 is provided with a central cavity which defines a mixing chamber 44 and which is co-axial with the cylindrical portion of the element extending a greater part of the length thereof.
  • the chamber 44 is of sufficient diameter to communicate with the inlet and outlet passages 24 and 26.
  • Magnetic stirring bar 18 rests at the bottom of chamber 44, the bar being a conventional stirring bar as can be seen more clearly by reference to FIG. 3.
  • stem 16 Also located within chamber 44 is stem 16. This stem is generally cylindrical in shape and is threaded at one end to be received within a threaded cavity 46 formed at the end of passage 24 in cap 10. A passage 48 extends the length of stem 16 and completes a path from inlet passage 24 through the stem to the interior of chamber 44.
  • the upper surface of flange 40 is provided with an annular groove within which an O-ring 50 is positioned. This O-ring prevents the passage of fluid between the mating surfaces of recess 20 and flange 40 when the retainer 14 positions the element 12 within the recess.
  • the cap 10 is provided with a plurality of holes 54 through which suitable bolts 56 project, the entire assembly being held to support 52 by nuts 58 secured to the bolts.
  • the cap, mixing chamber, stem and retainer are preferably made of stainless steel and O-ring 50 is a material such as polysulfide which exhibits high solvent resistance.
  • the mixing chamber 44 is filled with a starting eluant and a solvent of high elution power is pumped at high pressure via conduit 36, inlet passage 24, and passage 48 into the chamber.
  • Mixing is accomplished by the actuation of stirring bar 18 by means of a magnetic field external to the assembly, the stainless steel being non-magnetic and therefore not interfering with the operation of stirrer 18.
  • the high pressure mixture is forced out of the chamber 44 through passage 26 and conduit 38 to the chromatographic column.
  • the actual size of the chamber is determined by the shape of the gradient desired. The larger the chamber, the less steep is the gradient developed.
  • the device described is particularly adapted to a liquid chromatography, it also can be used for slurry packing small packing materials into columns.
  • the packing material is added to a carrier solvent in the desired slurry consistency and is poured into the mixing chamber. The slurry is then pumped from the mixing chamber to the column.
  • a device for developing a high pressure gradient 5 for liquid chromatography comprising:
  • a cap an element having a chamber therein; means for securing the element to said cap;
  • said securing means comprises a retainer operatively related to the recess and the element to hold said element within the recess.

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Fluid Mechanics (AREA)
  • Treatment Of Liquids With Adsorbents In General (AREA)

Abstract

An element having a chamber therein is secured to a device which is provided with inlet and outlet passages communicating with the chamber. A stirrer is positioned in the chamber and serves to mix liquid within the chamber with a fluid introduced to the chamber under high pressure via the inlet passage, the resultant mix being forced out of the chamber through the outlet passage.

Description

United States Patent Pfadenhauer [451 Aug. 20, 1974 Pri mary Examiner-John Adee Attorney, Agent, or FirmCushman, Darby &
[76] Inventor: Ernest H. Pfadenhauer, 2157 Miner Cushman St., Costa Mesa, Calif. 92627 [22] Filed: Dec. 11, 1973 [57] ABSTRACT [21] Appl' 423794 An element having a chamber therein is secured to a device which is provided with inlet and outlet passages [52] US. Cl. 210/198 C, 55/386 communicating with the chamber, A stirrer is posi- [51] Int. Cl B0ld 15/08 tioned in the chamber and serves to mix liquid within [58] Field of Search 210/31 C, 198 C; 55/386 the chamber with a fluid introduced to the chamber under high pressure via the inlet passage, the resultant [56] References Cited mix being forced out of the chamber through the out- UNITED STATES PATENTS let P 3,504,799 4 1970 Ogle 210/198 c 8 Claims, 3 Drawing Figures 3,583,230 6/1971 Patterson 210/198 C X HIGH PRESSURE GRADIENT CHAMBER FOR LIQUID CHROMATOGRAPHY BACKGROUND AND SUMMARY OF THE INVENTION Gradient elution is a useful technique in many applications of chromatography and is particularly applicable to high pressure liquid chromatography where high resolution and speed of analysis are obtainable. However, available gradient devices are complex and expensive. For example, one such device requires a substantial number of high pressure valves, a holding coil and a gradient chamber, whereas another known arrangement utilizes a plurality of pumps to develop the gradient.
The present invention is concerned with a simple, efficient gradient device which can be produced at a fraction of the cost of known devices and which permits accurate mixing for a precise gradient without introducing voids which would interfere with subsequent detection in the chromatographic column. This is accomplished by combining an element having a chamber therein and a cap device. The cap is provided with a suitable passage to direct a solvent under high pressure into the chamber to be mixed by a magnetic stirrer with an eluant within the chamber, the pressure forcing the mix from the chamber through a second passage in the cap to the liquid column where the analysis is made.
The invention now will be described in greater detail with reference to the accompanying drawings which illustrate a preferred embodiment of the invention and wherein:
FIG. 1 is a top plan view of a high pressure gradient chamber according to the invention;
FIG. 2 is a view partially in section taken along line 2-2 of FIG. 1; and
FIG. 3 is a view in section taken along lines 3-3 of FIG. 2.
Referring to the drawings, the basic components of the device are a cap 10, element 12, retainer 14, stem 16, and magnetic stirring bar 18. The structural details of these elements can most clearly be seen in FIGS. 2 and 3.
Cap is a generally cylindrical element. A cylindrical recess is provided at one end of the cap, this recess being threaded along a portion of its length as indi- 'cated at 22. A pair of passages are machined in the cap,
these passages communicating with the recess 20. One of these passages is designated as an inlet passage 24, while the other passage 26 serves as an outlet. The ends of passages 24 and 26 remote from the recess 20 communicate with internally threaded cavities 28 and 30 which receive conventional fittings 32 and 34, respectively. Fitting 32 is associated with a conduit 36 which is joined to a source of solvent moved under high pressure by a pump (not shown), while fitting 34 couples the outlet passage 26 to a liquid chromatographic column (not shown) via conduit 38.
' Element 12 is generally cylindrical and has an annular flange portion 40 at one end thereof. The external diameter of the flange is slightly less than the diameter of the recess 20 in cap 10. Consequently, element 12 is received within recess 20 as shown. In order to hold theelement within recess 20, retainer 14 is employed.
. 6 This retainer IS an annularly shaped device having external threads which cooperate with threads 22 within recess 20. The diameter of the passage through retainer 14 substantially corresponds to the diameter of the cylindrical portion of element 12. Consequently, retainer 14 is slipped over the end of element 12 and is screwed into recess 20 so as to engage the shoulders of the element which are defined by flange 40. Thus, element 12 is held in position within the recess 20 of cap 10. The retainer 14 is provided with recesses 42 in one face thereof, these recesses serving to accept a suitable tool for tightening the threaded retainer, and thus the element 12 within recess 20.
Element 12 is provided with a central cavity which defines a mixing chamber 44 and which is co-axial with the cylindrical portion of the element extending a greater part of the length thereof. The chamber 44 is of sufficient diameter to communicate with the inlet and outlet passages 24 and 26.Magnetic stirring bar 18 rests at the bottom of chamber 44, the bar being a conventional stirring bar as can be seen more clearly by reference to FIG. 3.
Also located within chamber 44 is stem 16. This stem is generally cylindrical in shape and is threaded at one end to be received within a threaded cavity 46 formed at the end of passage 24 in cap 10. A passage 48 extends the length of stem 16 and completes a path from inlet passage 24 through the stem to the interior of chamber 44.
In order to prevent leakage from the mixing chamber, the upper surface of flange 40 is provided with an annular groove within which an O-ring 50 is positioned. This O-ring prevents the passage of fluid between the mating surfaces of recess 20 and flange 40 when the retainer 14 positions the element 12 within the recess.
To mount the unit to a suitable support, shown as 52 in FIG. 2, the cap 10 is provided with a plurality of holes 54 through which suitable bolts 56 project, the entire assembly being held to support 52 by nuts 58 secured to the bolts.
The cap, mixing chamber, stem and retainer are preferably made of stainless steel and O-ring 50 is a material such as polysulfide which exhibits high solvent resistance.
In operation, the mixing chamber 44 is filled with a starting eluant and a solvent of high elution power is pumped at high pressure via conduit 36, inlet passage 24, and passage 48 into the chamber. Mixing is accomplished by the actuation of stirring bar 18 by means of a magnetic field external to the assembly, the stainless steel being non-magnetic and therefore not interfering with the operation of stirrer 18. The high pressure mixture is forced out of the chamber 44 through passage 26 and conduit 38 to the chromatographic column.
The actual size of the chamber is determined by the shape of the gradient desired. The larger the chamber, the less steep is the gradient developed.
While the device described is particularly adapted to a liquid chromatography, it also can be used for slurry packing small packing materials into columns. In such an arrangement, the packing material is added to a carrier solvent in the desired slurry consistency and is poured into the mixing chamber. The slurry is then pumped from the mixing chamber to the column.
What is claimed is: v
1. A device for developing a high pressure gradient 5 for liquid chromatography comprising:
a cap; an element having a chamber therein; means for securing the element to said cap;
4. A device as set forth in claim 3, wherein said securing means comprises a retainer operatively related to the recess and the element to hold said element within the recess.
5. A device as set forth in claim 3, further comprising sealing means within said recess engaging the element and the cap to prevent escape of fluid fromthe chamber except through the outlet passage.
6. A device as set forth in claim 1, wherein said element is provided with a cylindrical cavity to define the chamber, the device further comprisinga stern secured to said cap and projecting within the cavity, said stem having a passage therethrough communicating with the inlet passage to introduce the fluid under pressure to the interior of the chamber.
7. A device as set forth in claim 6, wherein said stirring means is located between the stem and the bottom of said cavity and is magnetically operable.
8. A device as set forth in claim 1, further comprising sealing means engaging the element and the cap to prevent escape of fluid from the chamber except through the outlet passage.

Claims (8)

1. A device for developing a high pressure gradient for liquid chromatography comprising: a cap; an element having a chamber therein; means for securing the element to said cap; inlet and outlet passages in said cap, said passages communicating with the chamber; and stirring means within said chamber for mixing fluid within the chamber with fluid introduced under pressure to the chamber through the inlet.
2. A device as set forth in claim 1, wherein said stirring means is magnetically operable.
3. A device as set forth in claim 1, wherein said cap includes a recess within which said element is secured.
4. A device as set forth in claim 3, wherein said securing means comprises a retainer operatively related to the recess and the element to hold said element within the recess.
5. A device as set forth in claim 3, further comprisiNg sealing means within said recess engaging the element and the cap to prevent escape of fluid from the chamber except through the outlet passage.
6. A device as set forth in claim 1, wherein said element is provided with a cylindrical cavity to define the chamber, the device further comprising a stem secured to said cap and projecting within the cavity, said stem having a passage therethrough communicating with the inlet passage to introduce the fluid under pressure to the interior of the chamber.
7. A device as set forth in claim 6, wherein said stirring means is located between the stem and the bottom of said cavity and is magnetically operable.
8. A device as set forth in claim 1, further comprising sealing means engaging the element and the cap to prevent escape of fluid from the chamber except through the outlet passage.
US00423794A 1973-12-11 1973-12-11 High pressure gradient chamber for liquid chromatography Expired - Lifetime US3830369A (en)

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3934456A (en) * 1974-07-22 1976-01-27 Varian Associates Solvent gradient generator for chromatography systems
US4628726A (en) * 1984-03-29 1986-12-16 Etd Technology, Inc. Analysis of organic compounds in baths used in the manufacture of printed circuit board using novel chromatographic methods
US4694682A (en) * 1984-03-29 1987-09-22 Etd Technology, Inc. Analysis of organic additives in plating baths using novel chromatographic methods in a mass balance approach
US4842730A (en) * 1986-09-17 1989-06-27 U.S. Philips Corporation Liquid chomatograph apparatus
US4857187A (en) * 1987-09-28 1989-08-15 The Government Of The U.S. As Represented By The Secretary Of The Department Of Health And Human Services Multistage mixer-settler centrifuge
US5112492A (en) * 1990-12-11 1992-05-12 Biotage Inc. Automated bubble trap
US5275723A (en) * 1992-07-06 1994-01-04 Sp Industries Ltd. Partnership Mobile phase reservoir
WO1996030757A2 (en) * 1995-03-31 1996-10-03 The Perkin-Elmer Corporation High-pressure micro-volume syringe pump
US6048496A (en) * 1996-06-05 2000-04-11 Gi Sciences Incorporated Mixer for liquid chromatograph
US10295512B2 (en) 2015-12-08 2019-05-21 Dionex Corporation Multi-lumen mixing device for chromatography
US11185830B2 (en) 2017-09-06 2021-11-30 Waters Technologies Corporation Fluid mixer
US11555805B2 (en) 2019-08-12 2023-01-17 Waters Technologies Corporation Mixer for chromatography system
US11821882B2 (en) 2020-09-22 2023-11-21 Waters Technologies Corporation Continuous flow mixer
US11898999B2 (en) 2020-07-07 2024-02-13 Waters Technologies Corporation Mixer for liquid chromatography
US11988647B2 (en) 2020-07-07 2024-05-21 Waters Technologies Corporation Combination mixer arrangement for noise reduction in liquid chromatography

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3504799A (en) * 1968-04-02 1970-04-07 Beckman Instruments Inc Sample injector
US3583230A (en) * 1968-06-12 1971-06-08 Sondell Research Dev Co Sample injection method and apparatus

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3504799A (en) * 1968-04-02 1970-04-07 Beckman Instruments Inc Sample injector
US3583230A (en) * 1968-06-12 1971-06-08 Sondell Research Dev Co Sample injection method and apparatus

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3934456A (en) * 1974-07-22 1976-01-27 Varian Associates Solvent gradient generator for chromatography systems
US4628726A (en) * 1984-03-29 1986-12-16 Etd Technology, Inc. Analysis of organic compounds in baths used in the manufacture of printed circuit board using novel chromatographic methods
US4694682A (en) * 1984-03-29 1987-09-22 Etd Technology, Inc. Analysis of organic additives in plating baths using novel chromatographic methods in a mass balance approach
US4842730A (en) * 1986-09-17 1989-06-27 U.S. Philips Corporation Liquid chomatograph apparatus
US5080784A (en) * 1986-09-17 1992-01-14 U.S. Philips Corporation Solvent mixing device for liquid chromatography
US4857187A (en) * 1987-09-28 1989-08-15 The Government Of The U.S. As Represented By The Secretary Of The Department Of Health And Human Services Multistage mixer-settler centrifuge
US5112492A (en) * 1990-12-11 1992-05-12 Biotage Inc. Automated bubble trap
US5407569A (en) * 1992-07-06 1995-04-18 Sp Industries Ltd. Partnership Mobile phase reservoir
US5275723A (en) * 1992-07-06 1994-01-04 Sp Industries Ltd. Partnership Mobile phase reservoir
WO1996030757A2 (en) * 1995-03-31 1996-10-03 The Perkin-Elmer Corporation High-pressure micro-volume syringe pump
WO1996030757A3 (en) * 1995-03-31 1996-11-07 Perkin Elmer Corp High-pressure micro-volume syringe pump
US6048496A (en) * 1996-06-05 2000-04-11 Gi Sciences Incorporated Mixer for liquid chromatograph
US10295512B2 (en) 2015-12-08 2019-05-21 Dionex Corporation Multi-lumen mixing device for chromatography
US11185830B2 (en) 2017-09-06 2021-11-30 Waters Technologies Corporation Fluid mixer
US11555805B2 (en) 2019-08-12 2023-01-17 Waters Technologies Corporation Mixer for chromatography system
US11898999B2 (en) 2020-07-07 2024-02-13 Waters Technologies Corporation Mixer for liquid chromatography
US11988647B2 (en) 2020-07-07 2024-05-21 Waters Technologies Corporation Combination mixer arrangement for noise reduction in liquid chromatography
US11821882B2 (en) 2020-09-22 2023-11-21 Waters Technologies Corporation Continuous flow mixer

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