DIRECT DRUG DETERMINATION BY SELECTIVE SAMPLE ENRICHMENT ON AN IMPRINTED POLYMER

A new approach to sample enrichment and analyte determination is reported. An imprinted dispersion polymer capable of molecular recognition of pentamidine (PAM), a drug used for the treatment of AIDS-related pneumonia, was used in solid-phase extraction in order to selectively retain PAM from a dilute solution. At a physiological concentration (30 nM) this gave an enrichment factor of 54 using a PAM-selective polymer whereas the enrichment factor on a benzamidine- (BAM-) imprinted reference polymer was only 14. The high selectivity of the polymer allowed the drug to be detected directly in the desorption step, thus eliminating the need for a successive chromatographic analysis. In this way,; PAM could be enriched and directly analyzed when present in low concentration in a urine sample.