The objective of the project was to develop a method for solid-phase extraction of local anaesthetics in plasma samples, based on the use of molecular imprinted polymers (MIPs). The MIP is developed to get more selective extraction and higher degree of sample clean-up compared with already existing methods. A template, pentycaine, was present during the polymerisation and was washed off and binding sites remain which are complementary to the template. The polymer was ground and sieved, particles between 25-40 mm were collected and packed in SPE columns. In this work a method was developed for SPE of bupivacaine and ropivacaine in human plasma. During development of the method the activation, the wash step and the elution step were investigated. The best activation was found to be 1 ml methanol followed by 1 ml water. The best wash step was found to be 2 ml 20% methanol in water followed by 0.5 ml 10% ethanol in acetonitrile. The use of 2 ml acetonitrile with 2% TEA and 6% water as elution solvent was found to be the best. During the investigation the recovery of the analyte and the appearance of the chromatogram was studied. The method obtained 89% recovery of the analyte and clean chromatogram. A validation of the method was made. Nine calibration points with different concentrations, between 2.0-498.7 nM, of ropivacaine and bupivacaine in human plasma were used. Four levels, between 4.5-300.0 nM, of control samples (QC) were analysed. The accuracy and the precision, both intra-day and inter-day, were calculated. The calculated accuracy was better than 10%, except for the QC sample of ropivacaine with concentration 4.5 nM which was difficult to analyse. The precision was better than 15% intra-day and 20% inter-day, except for QC sample 4.5 nM of ropivacaine. The limit of quantification (LOQ) for bupivacaine was 3.9 nM and for ropivacaine was 7.8 nM.