A simple, fast and cost effective method for detection and determination of dopamine in bovine serum

Abstract

In this work a simple, fast, sensitive and inexpensive method for determination of dopamine hydrochloride (DPH) by using potassium ferricyanide is described. The results showed that Fe(III) reduced to Fe(II) by dopamine hydrochloride at pH 1.5 and then Fe(II) reacted with potassium ferricyanide to form Prussian blue (KFe^III[Fe^II(CN)₆]). In this method the cells containing the sample solution were scanned with a scanner, then the color of each cell was analyzed with software written in visual basic (VB 6) media to red, green and blue values. The cells were built by creating holes in the Plexiglas® sheet using a laser. The dimensions of the identical cells were examined by Cr(III) solution with known concentrations. The results showed that the system had a linear range of 2–20 µg mL⁻¹ of DPH with a detection limit of 0.5 µg mL⁻¹. We obtained the reaction time for this system of 45 min when the solution pH was 1.5. This reaction time was previously reported as 35 min at pH 4. In the current method not only reaction time was reduced to 5 seconds but one of the serious interference species was removed by applying the microwave radiation. The scanner was used instead of spectrophotometer.