LIQUID-CHROMATOGRAPHIC DETERMINATION OF TACRINE AND ITS METABOLITES IN RAT BILE MICRODIALYSATES

A microbore liquid chromatographic method using a phenyl stationary ph ase was developed for the determination of 9-amino-1,2,3,4-tetrahydroa cridine (tacrine, THA) and its metabolites in microdialysis samples of bile. Analysis of microdialysis samples requires analytical methods w ith low detection limits and small sample volume requirements. The met hod uses a 1-mm I.D. phenyl column and fluorescence detection. A detec tion limit of 0.25 ng/ml in a 5-mu l sample was achieved for THA. This method was then used to determine THA and THA-1-ol in the bile dialys ate of a rat. Because of the small sample volume requirements, a 10-mi n temporal resolution was achieved for the microdialysis experiment. T he low detection limit allowed the THA concentration in the bile to be monitored for more than 4 h following a 1.0 mg/kg i.v. dose of THA.