Microextraction by packed sorbent of drugs and peptides in biological fluids

Detta är en avhandling från Universitetsservice US-AB, Stockholm, Sweden

Sammanfattning: Sample preparation as the first step in an analytical procedure has an important role, particularly in bioanalysis, because of the complexity of biological samples (blood plasma and urine). Biological matrix such as plasma and blood contains proteins, organic and inorganic salts, acids, bases and various organic compounds with similar chemistry to the analytes of interest. Thus the basic concept of a sample preparation method is to convert a real matrix into a format that is suitable for analysis by an analytical technique. Therefore the choice of an appropriate sample preparation method greatly influences the reliability and accuracy of the analysis results.The aim of this thesis was to develop and validate of microextraction by packed syringe (MEPS) as a fast, selective, accurate and fully automated sample preparation technique for determination of BAM peptides in human plasma and local anaesthtics in human plasma and urine samples using silica and polymer sorbents.First work presents use of MEPS technique online with LC-MS/MS as a tool for the quantification of BAM peptide in plasma samples. MEPS technique provides significant advantages such as the speed and the simplicity of the sample-preparation process. Compared with other extraction techniques, such as protein precipitation and ultrafiltration, MEPS gave cleaner samples and higher recovery.In the second work, MEPS technique was developed by using synthesized molecularly imprinted polymer (MIP) as a sorbent for selective quantification of a homologous series of local anaesthetics, containing lidocaine, ropivacaine, mepivacaine, and bupivacaine in human plasma and urine samples. Compared with other conventional sorbent, the use of MIP provides high selectivity of the extraction and decrease the matrix effect.