Simultaneous determination of Tl(I) and In(III) using a voltammetric sensor array

Abstract

A sensor array consisting of a chemically modified sensor in which 4-carboxybenzo-18-crown-6 was immobilized onto a screen-printed carbon nanofiber-modified electrode (crown-6-SPCNFE) and an ex-situ antimony film deposited on a screen-printed carbon nanofiber-modified electrode (ex-situ-SbSPCNFE) was applied for the resolution of the strong overlapped signals resulting from the simultaneous determination of Tl(I) and In(III) by stripping voltammetry. A Partial Least Squares model was constructed and good calibration curves of predicted vs. expected concentrations of the considered metal ions, with correlation coefficients higher than 0.98 for both training and test sets, were obtained. These results provided by the sensor array were compared with those obtained by a single electrode. Moreover, this sensor array was successfully applied for the voltammetric determination of both Tl(I) and In(III) in tap water, providing comparable results to those obtained by ICP-MS measurements.

Voltammetric determination of metal ions beyond mercury electrodes. A review

“…References [238][239][240][241][242] Tables 1-2 and Tables 3-12 which are of increasing concern in pharmaceutic industry and environmental protection due to their intensive use as catalysers.…”

“…In references[239,240] crown ethers are considered as modifiers and deposited via electrografting through diazonium salts. In[241] the electronic tongue comprises SPCNFEs modified with both antimony via ex-situ and a crown ether, whereas in[242] the four electrodes of the array are a SPCE, an ex-situ antimony SPCNFE and two peptide modified SPCNFEs. For data treatment artificial neural network (ANNs)[238][239][240] and partial least squares (PLS)[241,242] were considered.…”

Towards improving the electroanalytical speciation analysis of indium

“…Electroanalytical sensors offer great opportunities to quantify the total indium amount at micromolar concentrations levels, using ex-situ plated antimony film [18][19][20] or bismuth film [21] electrodes. Another study reported the analytical performance of the adsorptive stripping electrochemical techniques (AdSV) in terms of linear ranges of calibration and limits of detection [22].…”

Screen-Printed Electrodes Modified with “Green” Metals for Electrochemical Stripping Analysis of Toxic Elements

“…The working carbon layer can also be modified with novel carbon nanomaterials based on graphene, graphene oxide [ 112 ], carbon nanotubes, and carbon nanofibers [ 115 ], or carbon nanotubes/ionic liquid [ 116 ] that are added into the graphite carbon ink. Various sensor arrays, consisting of a combination of chemically modified SPEs and a commercial nanofiber-loaded SPE ex situ plated with Sb, have been applied for the simultaneous determination of metals that produce strongly overlapping stripping signals (Tl, In, Cd, Pb, Bi) in combination with chemometrical data treatment [ 115 , 117 ].…”