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US4448691A
Expired / Lapsed
US
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Liquid chromatographic method and apparatus with hollow fiber device for post-column derivatization
Assignee: Dow Chemical Co
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Filing: 1983-02-14
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Granted: 1984-05-15
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Expires: 2003-02-14
Abstract
Abstract Reagent is added to liquid chromatographic effluent to increase detection sensitivity of sample bands, or to enhance sensitivity with respect to interfering bands which overlap sample bands of interest, using one or more hollow fibers immersed within mobile reagent which is permeated through the walls of the fibers and, thus, ultimately diffused into the column effluent.
Inventors
- 👤 James C. Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:23
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/84; B; B01; B01D; B01D15/00; B01D15/08; B01D15/10; B01D15/24; B01D15/245; B01J; B01J19/00; B01J19/24; B01J19/2475; B01J4/00; B01J4/001; B01J4/04; B01J2219/00; B01J2219/00049; B01J2219/00051; B01J2219/00159; G01N1/00; G01N1/28; G01N1/38; G01N2001/381; G01N2030/8423; G01N2030/8429; G01N2030/8435
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
108 words
Liquid chromatographic apparatus comprising a chromatographic column means, means to add sample to the chromatographic column means, means to add eluent to the chromatographic column means, whereby the sample is eluted through the chromatographic column means, and component species thereof appear in chromatographically displaced form in the effluent of the chromatographic column means, the improvement which comprises a post-column reactor comprising a hollow fiber membrane through which the effluent of the chromatographic column means is fed to a liquid chromatographic detector, mobile reagent, said hollow fiber being in permeation contact with the mobile reagent for permeation transfer of the reagent into the effluent of the chromatographic column means.
Claim 2
Dependent Claim
108 words
Liquid chromatographic apparatus comprising a chromatographic column means, means to add sample to the chromatographic column means, means to add eluent to the chromatographic column means, whereby the sample is eluted through the chromatographic column means, and component species thereof appear in chromatographically displaced form in the effluent of the chromatographic column means, the improvement which comprises a post-column reactor comprising a hollow fiber membrane through which the effluent of the chromatographic column means is fed to a liquid chromatographic detector, mobile reagent, said hollow fiber being in permeation contact with the mobile reagent for permeation transfer of the reagent into the effluent of the chromatographic column means.
Claim 3
Dependent Claim
14 words
The apparatus of claim 1 wherein said post-column reactor comprises multiple hollow fiber membranes.
Claim 4
Dependent Claim
24 words
The apparatus of claim 1 comprising a reservoir means containing mobile reagent, wherein the reservoir means is of a type noncontinuously replenished by reagent.
Claim 5
Dependent Claim
110 words
Method of analyzing samples by liquid chromatography comprising adding sample to a chromatographic column means, adding eluent to the chromatographic column means effective to chromatographically displace species of the sample from the chromatographic column means, whereby chromatographically displaced sample species appear ultimately in the effluent of the chromatographic column means, the improvement which comprises feeding the effluent of the chromatographic column means through the internal bore of a hollow fiber membrane, ultimately to a liquid chromatographic detector, and prior to detection, using the hollow fiber membrane for permeation transfer of a mobile reagent into the effluent of the chromatographic column means to enhance the sensitivity of detection of the method.
Claim 6
Dependent Claim
110 words
Method of analyzing samples by liquid chromatography comprising adding sample to a chromatographic column means, adding eluent to the chromatographic column means effective to chromatographically displace species of the sample from the chromatographic column means, whereby chromatographically displaced sample species appear ultimately in the effluent of the chromatographic column means, the improvement which comprises feeding the effluent of the chromatographic column means through the internal bore of a hollow fiber membrane, ultimately to a liquid chromatographic detector, and prior to detection, using the hollow fiber membrane for permeation transfer of a mobile reagent into the effluent of the chromatographic column means to enhance the sensitivity of detection of the method.
Claim 7
Dependent Claim
23 words
The method of claim 4 using multiple hollow fiber membranes connected between the chromatographic column means and detector and immersed within mobile reagent.
Claim 8
Dependent Claim
16 words
The method of claim 4 wherein said mobile reagent is contained within a noncontinuously replenished reservoir.
References Cited (Backward Citations)
US4251218A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |