ON-LINE SOLID PHASE EXTRACTION COUPLED WITH LIQUID CHROMATOGRAPHY TANDEM MASS SPECTROMETRY FOR THE DETERMINATION OF CODEINE IN HUMAN PLASMA

A specific LC-MS/MS method was developed and validated for automated determination of codeine in human plasma, using on-line solid phase extraction (SPE) system coupled with positive ion electrospray ionization tandem mass spectrometry. The method allowed plasma direct injection onto cartridge without sample pre-treatment. Total analysis time per run was 3 min, allowing high-throughput for codeine determination. SPE on-line along a monolithic column (Chromolith Performance RP-18e, 100 mm x 4.6 mm) demonstrated to be highly effective in terms of backpressure, separation speed and peak asymmetry...