Electroanalysis of Norepinephrine at Bare Gold Electrode Pure and Modified with Gold Nanoparticles and S‐Functionalized Self‐Assembled Layers in Aqueous Solution

Abstract

Gold nanoparticles (Au-NPs), cystamine (CA) and 3,3'-dithiodipropionic acid (DTDPA) modified gold bare electrodes were applied in voltammetric sensors for simultaneous detection of norepinephrine (NEP), ascorbic (AA) and uric (UA) acids. A linear relationship between norepinephrine concentration and current response was obtained in the range of 0.1 mM to 600 mM M with the detection limit 0.091 mM for the electrodes modified at 2D template and in the range of 0.1 mM to 700 mM M with the detection limit 0.087 mM for the electrodes modified at 3D template The results have shown that using modified electrodes it is possible to perform electrochemical analysis of norepinephrine without interference of ascorbic and uric acids, whose presence is the major limitation in norepinephrine determination at a bare gold electrode. The modified SAMs electrodes show good selectivity, sensitivity, reproducibility and high stability.

Electroanalysis of Norepinephrine at Bare Gold Electrode Pure and Modified with Gold Nanoparticles and S‐Functionalized Self‐Assembled Layers in Aqueous Solution. Part II

“…This is in agreement with literature data, as it has been shown that the Au nanoparticles of diameters between 2.6 nm and 20 nm could be expected when the absorption maximum appears between 514 nm and 530 nm, respectively [33,34]. The diameter of the Au-NPs particles used in this study was the same as that reported in the earlier studies [22,33,35] when the same procedure of Au colloidal solution preparation as in the present paper was used.…”

“…Au=Au À NPs : ðAu The electrodes treatment after modification and electrochemical experiments as well as the way of electrodes storage were the same as described earlier [22].…”

“…The solutions were prepared prior to use from deionized water purified in a Millipore Milli-Q system. A monodispersed Au-colloidal solution was prepared according to procedure described elsewhere [22,23,24]. All solutions under investigation were deaerated by blowing highly pure argon before measurements.…”

“…The new voltammetric sensors are applied for simultaneous detection of norepinephrine, AA and UA in aqueous solutions. A comparison with the earlier published results on the modified electrodes using dithiodipropionic acid (DTDPA) is made [22].…”

Epinephrine Oxidation in the Presence of Interfering Molecules on Gold and Gold Electrodes modified with Gold Nanoparticles and Thiodipropionic Acid in Aqueous Solution. A Comparative Study

“…As shown, the colloidal gold gives the maximum absorbance at about 520 nm. This length was the same as that obtained earlier [29,30,33,34]. It is known that the Au nanoparticles of diameters between 2.6 nm and 20 nm could be expected when the absorption maximum appears between 514 nm and 530 nm.…”