Spectrofluorimetric determination of dopamine receptor antagonist LE 300 in mice plasma.

A simple, rapid and highly sensitive spectrofluorimetric method was developed for determination of a novel type of dopamine receptor antagonist LE300 in mouse plasma. The method is based on measuring the native fluorescence of LE-300 in methanol at 343 nm after excitation at 280 nm. The fluorescence concentration plot was rectilinear over the range of 3.5-100 ng/mL with a lower detection limit of 1.0 ng/mL and quantification limit of 3.5 ng/mL. The method was statistically validated for linearity, accuracy, precision and selectivity according to the International Conference on Harmonization guidelines. The accuracy and precision results was expressed as % recovery and relative standard deviation (RSD). The accuracy for LE-300 was in the range 95.5-103.6% and RSD values were in the range of 0.21-1.55% of the theoretical value. The method was successfully applied to the analysis of LE-300 in mice plasma. The results were compared statistically with those obtained by the reported method and were found to be in good agreement, which could be applied in a pharmacokinetic study.