EP0177344A2
Expired / Lapsed
EP
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Serum pretreatment for tricyclic antidepressant drug assays and kit therefor
Assignee: Syntex USA LLC
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Filing: 1985-10-02
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Granted: —
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Expires: 2005-10-02
Abstract
Abstract Serum is passed through a column containing alkylated silica gel. The column is then washed with a mixture comprising from about 50 to 85 volume percent of an aqueous buffered medium of pH from about 3.5 to 5.0 and from about 15 to 50 volume percent of an organic solvent containing from 1 to 6 carbon atoms and from 1 to 5 heteroatoms selected from oxygen, nitrogen, and sulfur. The tricyclic antidepressant drug is removed from the column with an eluent mixture comprising from about 0 to 75 volume percent of an aqueous buffered medium of pH of about from 6 to 8 and from about 25 to 100 volume percent of one or more organic solvents containing from 1 to 6 carbon atoms and from 1 to 5 heteroatoms selected from oxygen, nitrogen, and sulfur. In this way, a tricyclic antidepressant drug sample, free from interfering metabolites, for use in assay determinations is obtained.
Inventors
- 👤 Christine Glen Collins
- 👤 Susan Pankay
- 👤 Anna Jaklitsch
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 19:28
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/94; G01N33/9466; Y; Y10; Y10T; Y10T436/00; Y10T436/14; Y10T436/141111
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
209 words
A method for preparing a serum sample for determination of a tricyclic antidepressant drug in an assay, which method comprises: (a) adding said serum sample to a chromatographic column containing alkylated silica gel; (b) washing the column with a wash solution comprising from about 15 to 50 volume percent of an organic solvent of from 1 to 6 carbon atoms and from 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 50 to 85 volume percent of an aqueous buffered medium having a pH of about from 3.5 to 5.0, in an amount sufficient to substantially remove metabolites of the tricyclic antidepressant drug from said column but insufficient to remove the tricyclic antidepressant drug from the column; and (c) eluting the tricyclic antidepressant drug with an elution solution comprising from about 25 to 100 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 0 to 75 volume percent of an aqueous buffered medium having a pH of from about 6 to 8 in an amount sufficient to elute a substantial portion of the tricyclic antidepressant drug from the column.
Claim 2
Independent Claim
209 words
A method for preparing a serum sample for determination of a tricyclic antidepressant drug in an assay, which method comprises: (a) adding said serum sample to a chromatographic column containing alkylated silica gel; (b) washing the column with a wash solution comprising from about 15 to 50 volume percent of an organic solvent of from 1 to 6 carbon atoms and from 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 50 to 85 volume percent of an aqueous buffered medium having a pH of about from 3.5 to 5.0, in an amount sufficient to substantially remove metabolites of the tricyclic antidepressant drug from said column but insufficient to remove the tricyclic antidepressant drug from the column; and (c) eluting the tricyclic antidepressant drug with an elution solution comprising from about 25 to 100 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 0 to 75 volume percent of an aqueous buffered medium having a pH of from about 6 to 8 in an amount sufficient to elute a substantial portion of the tricyclic antidepressant drug from the column.
Claim 3
Dependent Claim
21 words
The method of Claim 1 wherein the silica gel is alkylated with alkyl groups of from 1 to 6 carbon atoms.
Claim 4
Dependent Claim
14 words
The method of claim 1 or Claim 2 wherein said alkyl group is ethyl.
Claim 5
Independent Claim
16 words
The method of any one of the preceding claims, wherein said organic solvent is an alkylnitrile.
Claim 6
Dependent Claim
11 words
The method of Claim 4 wherein said organic solvent is acetonitrile.
Claim 7
Independent Claim
25 words
The method of any one of the preceding claims, wherein said aqueous buffered medium in Step b contains a metal salt of a carboxylic acid.
Claim 8
Dependent Claim
12 words
The method of Claim 6 wherein said metal salt is sodium acetate.
Claim 9
Independent Claim
29 words
The method of any one of the preceding claims, wherein said aqueous buffered medium in Step b additionally contains an alkyl sulfonate of from 5 to 7 carbon atoms.
Claim 10
Dependent Claim
12 words
The method of Claim 8 wherein said alkyl sulfonate is heptane sulfonate.
Claim 11
Independent Claim
29 words
The method of any one of the preceding claims, wherein the elution solution in Step c comprises two different organic solvents in the ratio of about 1:1 to 1:2.
Claim 12
Dependent Claim
16 words
ll. The method of Claim 10 wherein the organic solvents are an alkylnitrile and an alcohol.
Claim 13
Dependent Claim
13 words
The method of Claim 10 wherein the organic solvents are acetonitrile and methanol.
Claim 14
Independent Claim
22 words
The method of any one of the preceding claims, wherein the aqueous buffered medium in Step c is an aqueous phosphate buffer.
Claim 15
Dependent Claim
19 words
The method of Claim 1 wherein said tricyclic antidepressant drug is selected from amitriptyline, impramine, desmethylimipramine, doxepin and desmethyldoxepin.
Claim 16
Dependent Claim
157 words
A kit for purifying a serum sample to give a tricyclic antidepressant drug sample for use in an assay for said drug, which kit comprises - (a) a column containing silica gel alkylated with alkyl groups, (b) a wash solution comprising from about 15 to 50 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 50 to 85 volume percent of an aqueous buffered medium having a pH of about from 3.5 to 5.0; and (c) an eluent solution comprising about from 25 to 100 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur, and about from 0 to 75 volume percent of an aqueous buffered medium having a pH of about from 6 to 8.
Claim 17
Dependent Claim
157 words
A kit for purifying a serum sample to give a tricyclic antidepressant drug sample for use in an assay for said drug, which kit comprises - (a) a column containing silica gel alkylated with alkyl groups, (b) a wash solution comprising from about 15 to 50 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur and from about 50 to 85 volume percent of an aqueous buffered medium having a pH of about from 3.5 to 5.0; and (c) an eluent solution comprising about from 25 to 100 volume percent of an organic solvent of from 1 to 6 carbon atoms and 1 to 5 heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur, and about from 0 to 75 volume percent of an aqueous buffered medium having a pH of about from 6 to 8.
Claim 18
Dependent Claim
21 words
A tricyclic antidepressant drug sample obtained from a serum sample by the method of any one of Claims 1 to 14.
References Cited (Backward Citations)
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