Inter-day precision was evaluated by repeating the intra-day
precision study on five different days. Precision was assessed by
calculating the mean, standard deviation (SD), and the coefficient of
variation (RSD%) of these values.
Intra-day precision was determined by preparing and
analyzing, on the same day, five replicates of three different concentrations
in the range 0.1e3.0 mg/mL for octopamine, tyramine,
N-methyl-tyramine, hordenine and 10.0, 40.0, 80.0 mg/mL for
synephrine.