Catecholamines dopamine, norepinephrine and epinephrine serve as the most important neurotransmitters in the central and peripheral nervous systems [1]. Several psychiatric, neurological and cardiovascular diseases are associated with dopamine, epinephrine and serotonin levels and their concentrations in plasma are often useful for diagnosis and monitoring of therapeutic and pharmacodynamics effects. [2,3]. In presented work, dispersive micro solid phase extraction (DMSPE) was applied. In DMSPE in order to extract target analytes, the defined amount of solid sorbent is dispersed in the aqueous sample solution by ultrasound energy, a magnetic stirrer or a vortex device. In the following, for detection analytes high performance liquid chromatography (HPLC-UV) was used. For the sensitive and selective extraction and determination of target analytes, MNPs have been combined with the syringe–to–syringe magnetic solid–phase microextraction (SS–MSPME) method. The sorbent was characterized using fourier transform-infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Various parameters affecting the extraction efficiency such as pH, ionic strength of sample solution, amount of sorbent (mg), volume of eluent solvent (µl), adsorption and desorption time (min) were optimized. Under optimum conditions, calibration graphs of target analytes were found to be linear in the concentration of range of 0.5-300 µg. L-1 with correlation coefficients (r2) of more than 0.9990.
