Simplified micro-scale procedure for preparing samples for theophylline determination by liquid chromatography.

Abstract:

:We describe an improved procedure for the preparation of plasma or serum for determination of theophylline by reverse phase high-performance liquid chromatography. Quantitative results are available in less than 30 min from receipt of sample. The chromatogram is complete in 8 to 16 min, which includes the use of an internal standard. Sample preparation consists of simple solvent denaturation of the sample proteins, and centrifugation to remove protein before chromatography. No precolumn is required to pretect the separating column. No interference was noted when sodium or lithium heparin or ethylenediaminetetraacetate were used as anticoagulants, but citrate treatment proved to be unsatisfactory because of a highly absorbing band that eluted with the same retention volume as theophylline.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Nelson JW,Cordry AL,Aron CG,Bartell RA

subject

Has Abstract

pub_date

1977-01-01 00:00:00

pages

124-6

issue

1

eissn

0009-9147

issn

1530-8561

journal_volume

23

pub_type

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