Analytical Sciences

Spectrophotometric Determination of Dopamine Hydrochloride in Pharmaceutical, Banana, Urine and Serum Samples by Potassium Ferricyanide-Fe(III)

Li GUO,* Yan ZHANG,** and Quanmin LI*

*College of Chemistry and Environmental Science, Henan Normal University, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, P. R. China
**College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, P. R. China

In the present work, we developed a simple, sensitive and inexpensive method to determine dopamine hydrochloride using potassium ferricyanide-Fe(III) by spectrophotometry. The results show that Fe(III) is deoxidized to Fe(II) by dopamine hydrochloride at pH 4.0, and then Fe(II) reacts with potassium ferricyanide to form a soluble prussian blue (KFe^III[Fe^II(CN)₆]). The absorbance of this product was monitored over time using a spectrophotometer at an absorption maximum of 735 nm, and the amount of dopamine hydrochloride could be calculated based on the absorbance. A good linear relationship of the concentration of dopamine hydrochloride versus absorbance was observed, and a linear regression equation of A = 0.022 + 0.16921C (μg mL⁻¹) was obtained. Moreover, the apparent molar absorption coefficient for the indirect determination of dopamine hydrochloride was 3.2 × 10⁴ L mol⁻¹ cm⁻¹. This described method has been used to determine dopamine hydrochloride in pharmaceutical, banana, urine and serum samples with satisfactory results.

J-STAGE: View this article in J-STAGE