Spectroelectrochemical data of dopamine/epinephrine mixtures by combining amperometry and molecular fluorescence
Description
This dataset contains emission spectra obtained through the amperometry-based spectroelectrochemical analysis of solutions containing mixtures of dopamine and epinephrine in a phosphate buffer (pH 7.0). The analysis consisting in measuring emission spectra while amperograms were being measured at a fixed potential, doing so in three different potentials. These measurements used an Cary Eclipse spectrofluorometer (Agilent Technologies), an Autolab PGSTAT 101 (Metrohm), DRP-110 screen printed electrodes (DropSens) and a custom-made cell. Also provided are the 3D model of an angular holder to support the optical fiber probe and the arduino code for an Arduino Pro Micro used to syncronize the measurements through the PGSTAT's DB15 DIO port.
Files
Steps to reproduce
Two sets of standard solutions, one for calibration, containing a set of eight orthogonal mixtures of both analytes, and a set of 4 mixtures for validation and comparison were prepared by diluting water-based stock solutions in volumetric flasks. The solutions were prepared in a 0.1 mol.L-1 phosphate buffer, pH 7.0. The spectroelectrochemical cell was 3D printed in polylactic acid, with a female SMA (SubMiniature version A) connector attached to the top piece, allowing for replicable optical fibre threading. It was also projected for an incidence angle of 30°, facilitating the insertion and change of samples from the top opening. The space around the electrodes’ surface was sealed with an o-ring held in place by compressive tension around its outside diameter and against the screen printed electrode (DRP-110 SPEs made by DropSens), avoiding leakage during its use. Also present is an angular adapter to compensate for the Cary Eclipse optic fibre support angle. The spectrofluorometer (Agilent's Cary Eclipse) was set for excitation at 280 nm, with emission being measured from 297 to 400 nm in a loop, using excitation and emission slits set at 10 and 5 nm of bandpass respectively. Measurements were performed using amperograms with a potentiostat (Metrohm's Autolab PGSTAT 101) at potentials around the oxidation peak, at +0.1 V, +0.3 V and +0.5 V, each lasting 400 seconds. The solution on the electrode surface was renewed between potential changes.
Institutions
- Universidade Federal da ParaibaPB, Joao Pessoa