The Effect of Salt on Microextraction Dopamine in Human Blood Plasma Sampels with Dispersive Liquid- liquid Microextraction

A new method of dispersive liquid-liquid microextraction (DLLME) combined with Spectrophotometry UV-Vis was proposed for the dopamin determination using (6 [monoboromo-panta-N-acotil-L-phenil alanino] -α-cyclodextrin) (3a-e-CD) as chelating agent from human blood plasma samples. This is a very simple and rapid method for the extraction and preconcentration of dopamin from human blood plasma sample. In this method، theappropriate mixture of extraction solvent (including 3a-e-CD) and disperser solvent (acton) was injected rapidly into the aqueous sample by syringe. Then، cloudy solution was formed. The mixture was centrifuged and the sediment on the bottom of the conical test tube removedthen injected to the cell sphectrophotometry and diluted with organic solvent. Some important parameters، such as kind and volume of extraction and disperser solvent، concentration of the chelating agent، extraction time، centrifuge time، pH and ionic strength of the aqueous solution were optimized. Under the optimal conditions، the enrichment factor and extraction recoveries were 295، %98-102% respectively. The linear range 10-400ppm and limit detection 0. 265 ppm were determined. The relative standard detection (R. S. D%) for 50 ppm of dopamine was 4/49% (n=5). The performance of the proposed technique was evaluated for determination of dopamine in blood plasma.