Direct Injection of Redissolved Cell Culture Media into a Single-Column Liquid Chromatography Coupled to Mass Spectrometry for the Measurement of PGE2

The traditional approach to assessing eicosanoids in cell cultures by liquid or gas chromatography coupled to mass spectrometry involves time-consuming procedures such as derivatisation, degradation, solid-phase extraction, liquid- liquid extraction, thin layer chromatography and sometimes, combination of all these procedures prior to the injection of the sample in the chromatography system. The performance of a method that allows the direct injection of redissolved cell culture media into a single-column liquid chromatography instrument coupled to mass spectrometry is evaluated. The ex- ternal standard calibration curves were linear between 1-50 ng/ml for Williams' medium E and L-15 medium. The limit of detection and quantification were 0.5 and 1 ng/ml in both media respectively. The recovery values were 98.6% for Wil- liams' medium E and 100.3% for L-15 medium. The internal standard method was not used for quantitative purposes due to the variability of the response factor. The proposed method has potential for broad implementation in monitoring bio- markers in cell cultures.