A Rapid and Sensitive HPLC-Fluorescence Method for Determination of Mirtazapine and Its two Major Metabolites in Human Plasma

A rapid and sensitive hplc method has been developed for the quantification of mirtazapine (mrz), a noradrenergic and specific serotonergic inhibitor antidepressant (nassa) and its two major metabolites n-desmethyl mirtazapine (ndm) and 8-hydroxymirtazapine (8-ohm) in human plasma. the separation was achieved using chromolith c18 column and a mobile phase of acetonitrile: phosphate buffer (ph = 3, 20:80, v/v) in isocratic mode at a flow rate of 2 ml/min. a fluorescence detector was set at 290 and 350 nm for excitation and emission, respectively. zolpidem was used as the internal standard. liquid-liquid extraction was applied for sample clean up. all analytes were eluted in less than 5 minutes with loq of 1 ng/ml for mrz and 2 ng/ml for both ndm and 8-ohm. the developed method was successfully applied to quantify mrz and its metabolites in plasma of a healthy volunteer.