Determination of serum tulobuterol concentrations by mass fragmentography: comparison with an electron-capture gas chromatographic method.

A simple and sensitive method is reported for the quantitative determination of the bronchodilator tulobuterol in human serum. Tulobuterol and an internal standard were extracted from alkalinized serum with ether and then back-extracted into dilute hydrochloric acid. After alkalinization and extraction of the aqueous solution, the extract was evaporated to dryness. The residue was silylated and subjected to mass fragmentography.