Luminescent determination of dopamine using a camera

It is shown that the interaction of dopamine with fluorescamine can be used as a basis for the luminescent determination of dopamine using a camera, since the product formed as a result of this interaction is characterized by a luminescence maximum in the visible region (485 nm), and a light-emitting diode emitting light in the near ultraviolet region (395 nm) is sufficient to excite the luminescence. The reaction should be carried out at pH 8–8.5 in a phosphate buffer solution for 5 min; fluorescamine should be added to the reaction mixture last. Some analytical characteristics of the determination using a camera are assessed and compared with the characteristics of a similar determination of dopamine using a professional spectrofluorometer and spectrophotometer. The detection limits of dopamine using a camera, spectrophotometer and spectrofluorometer were 1.8, 1.6 and 0.5 μM, the range of determined contents was 5.4–50 μM, 4.8–100 μM, 1.5–100 μM, respectively. The presence of common inorganic ions, the content of which is 10 times higher than the content of dopamine, does not interfere with the determination. The proposed method for determining dopamine can be used for quality control of drugs.