US5366601A
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US
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Method for separating ionic species using capillary electrophoresis
Assignee: Waters Technologies Corp
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Filing: 1992-10-20
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Granted: 1994-11-22
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Expires: 2012-10-20
Abstract
Abstract A technique for separating, identifying and measuring ions in solution by capillary zone electrophoresis is described, which provides improved sensitivity and resolution of anionic species. The method involves introducing a sample containing the ionic species into a narrow bore capillary filled with a carrier electrolyte containing a selected light-absorbing anion. An electrical potential is applied across the capillary column causing the ions to elute according to their ionic mobility. Both UV absorbing and UV-transparent ions can be detected and quantitated by UV/visible photometric monitoring.
Inventors
- 👤 William R. Jones
- 👤 Petr Jandik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:54
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/447; G01N27/44704; G01N27/44717; G01N27/44721
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
90 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary; b) immersing the capillary in a carrier electrolyte containing a salt selected from the group consisting of molybdate, tungstate, ferrocyanide, ferricyanide, bromide, iodide and dichromate; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
Claim 2
Independent Claim
90 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary; b) immersing the capillary in a carrier electrolyte containing a salt selected from the group consisting of molybdate, tungstate, ferrocyanide, ferricyanide, bromide, iodide and dichromate; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein the salt is a sodium salt having a concentration of from about 1.0 mM to about 20 mM.
Claim 4
Dependent Claim
17 words
The method of claim 1 wherein electrical voltage is from about 5 KV to about 40 KV.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein an electromigration additive is added to the sample.
Claim 6
Dependent Claim
26 words
The method of claim 4 wherein the electromigration additive is selected from the group consisting of an octanesulfonate salt, a carbonate salt and a citrate salt.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein the carrier electrolyte additionally contains an electroosmotic flow modifier.
Claim 8
Dependent Claim
26 words
The method of claim 6 wherein the electroosmotic flow modifier is selected from the group consisting of a cellulose, a glycol, a surfactant and a polyacrylamide.
Claim 9
Dependent Claim
22 words
The method of claim 7 wherein the electroosmotic flow modifier is selected from the group consisting of methylcellulose, hydroxypropylmethylcellulose and Tween 20.
Claim 10
Dependent Claim
23 words
The method of claim 6 wherein the electroosmotic flow modifier is selected from the group consisting of guanidine, diaminononane, di-n-butylamine and 3-N,N-dimethylpalmitylammonia propanesulfonate.
Claim 11
Dependent Claim
18 words
The method of claim 1 wherein the capillary has an electroosmotic flow modification to the capillary inner surface.
Claim 12
Dependent Claim
35 words
The method of claim 10 wherein the electroosmotic flow modification is a coating of the capillary inner surface with a substance selected from the group consisting of polyethylene glycol, polymethylsiloxane and polybutadiene maleic acid copolymer.
Claim 13
Independent Claim
104 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary; b) immersing the capillary in a carrier electrolyte containing a chromate or vanadate salt and an electroosmotic flow modifier selected from the group consisting of a cellulose, a glycol, a surfactant, a polyacrylamide, guanidine, diaminononane, di-n-butylamine and 3-N,N-dimethylpalmitylammonia propanesulfonate; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
Claim 14
Independent Claim
104 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary; b) immersing the capillary in a carrier electrolyte containing a chromate or vanadate salt and an electroosmotic flow modifier selected from the group consisting of a cellulose, a glycol, a surfactant, a polyacrylamide, guanidine, diaminononane, di-n-butylamine and 3-N,N-dimethylpalmitylammonia propanesulfonate; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
Claim 15
Independent Claim
101 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary whose inner surface is coated with a substance selected from the group consisting of polyethylene glycol, polymethylsiloxane and polybutadiene maleic acid copolymer; b) immersing the capillary in a carrier electrolyte containing a chromate or vanadate salt; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
Claim 16
Independent Claim
101 words
A method for detecting anions in a sample using capillary zone electrophoresis comprising the steps of: a) introducing the sample into a capillary whose inner surface is coated with a substance selected from the group consisting of polyethylene glycol, polymethylsiloxane and polybutadiene maleic acid copolymer; b) immersing the capillary in a carrier electrolyte containing a chromate or vanadate salt; c) applying an electrical current under conditions appropriate for the anions in the sample to move along the capillary toward the detection electrode, thereby causing separation of the anions to occur; and d) detecting the anions indirectly using a UV/visible photometric detector.
References Cited (Backward Citations)
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