DEVELOPMENT OF AN INNOVATIVE QUANTITATIVE METHOD FOR DOPAMINE AND A DOPAMINE AGONIST USING LIQUID CHROMATOGRAPHY COUPLED TO MASS SPECTROMETRY

Depression Disorder is a frequent debilitating condition worldwide posing a significant global health burden. Along the years there have been different ways to alleviate the symptoms even though treatment options are challenged by the complex and poorly understood nature of its physiological pathology. Based on what is known and the current medication available, this study introduces a new highly sensitive LC-MS/MS method that has been developed and validated for the quantification of Dopamine and (-)-OSU6162 a potential breakthrough compound for a more efficient antidepressant therapy. Protein precipitation with acetonitrile of a plasma sample where the internal standard was added was performed followed centrifugation, supernatant evaporation until dry and reconstituted in milli-Q water + 0.1% formic acid for HPLC analysis. The chromatography was performed with a hypersil BDS C18 column with gradient elution of 0.1% formic acid in water or in methanol. Multiple reaction monitoring (MRM) was performed using mass spectrometry and source, curtain and exhaust gas, compound specific mass spectrometric parameters and MRM transitions for Dopamine and (-)-OSU6162 were optimized. The method was developed and validated based on the current FDA guidelines, ensuring accuracy, precision, sensitivity, selectivity, recovery, matrix effects, stability, carry-over and dilution for a linear range of 10nM-250nM for Dopamine and 50nM-2000nM for (-)-OSU6162. Applicability of the described method was demonstrated through analysis of serum samples from a previous study where (-)-OSU6162 was administrated. The new developed LC-MS/MS method represents a significant advancement in antidepressant research, offering a rapid and accurate means of quantifying Dopamine and (-)-OSU6162. This methodology gives us an opening for a deeper understanding of the underlying mechanisms of depression and the exploration of more effective treatment options.