Subnanomolar detection of ions using thin voltammetric membranes with reduced Exchange capacity

Xu, Kequan; Crespo, Gastón A.; Cuartero, María

doi:10.1016/j.snb.2020.128453

Cited by 14 publications

(23 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[80] Applications of voltammetric mode in relation to ISEs were developed mainly by Bakker, Crespo and Cuartero with coworkers. [79,[81][82][83] A significant advantage of direct voltammetric mode for ISE is application of a membrane with a few ionophores, opening possibility of effective determination of a series of ions, in one measurement cycle. Figure 2 shows exemplary voltammetric curves for ISE with lithium, sodium and potassium ionophores, recorded in solutions containing Li + , Na + and K + -ions.…”

Section: 2voltammetric Methodsmentioning

confidence: 99%

Solid‐Contact Ion‐Selective Electrodes Paving the Way for Improved Non‐Zero Current Sensors: A Minireview

2021

View full text Add to dashboard Cite

Potentiometric ion-selective electrodes (ISEs) are established tools useful for the determination of activity of many ions with high selectivity. These sensors, developed originally for zerocurrent conditions, are of interest for other sensing protocols, requiring tailored construction optimization with the ultimate goal to offer higher sensitivity, extended response range, offering more robust sensors, or minimizing calibration and pretreatment procedures. Among the different possibilities, the proposed electrochemical trigger applied for the sensing of "redox inactive ions" offers important advantages and gains significant attention. The non-zero current applications of ISEs are typical for internal-solution free systems; thus, the optimization of all-solid-state transducers receives significant research attention. The aim of this Minireview is to summarize recent research in in the field, focusing on improvements of transducers and electrochemically triggered ion-selective sensors.

show abstract

Section: 2voltammetric Methodsmentioning

confidence: 99%

Solid‐Contact Ion‐Selective Electrodes Paving the Way for Improved Non‐Zero Current Sensors: A Minireview

2021

View full text Add to dashboard Cite

show abstract

“…Xu et al explored the possibility of lowering the limit of detection of thin ion-selective membranes back-contacted with POT. , The authors used an electrochemical protocol reported earlier based on the accumulation of Ag + by diffusional mass transport and stripping. During the accumulation step, a constant potential was applied to keep POT in its neutral form, followed by anodic stripping.…”

Section: New Ion-selective Readout Principles and Methodologiesmentioning

confidence: 99%

“…29 In later work, the same authors reported on a lowering of the abovementioned detection limit down to 0.05 nM by reducing the amount of the cation exchanger in the membrane phase from 40 to 10 mmol/kg. 30 The optimized electrochemical protocol was used for the detection of nanomolar levels of silver in environmental water samples.…”

Section: Analytical Chemistrymentioning

confidence: 99%

Potentiometric Sensing

2020

View full text Add to dashboard Cite

“…In recent years, increasing progress has been made in the research field of ion-selective electrodes (ISEs) based on polymeric ion-selective membranes (ISMs) that are interrogated using dynamic electrochemical techniques. 1 The measurements go beyond the traditional zero-current interrogation in potentiometry to pursue challenging analyses based on calibration-free sensors, 2 titration of confined samples, 3 the improvement of the limit of detection, 4 the simultaneous determination of multiple analytes, 5 high-concentration discrimination, 6 and the extension of the linear range of response, 7 among others. Principally, the use of all-solid-state electrodes based on a conducting polymer as the ion-to-electron transducer material with the ISM on top (i.e., a double-layer design) seems to stand out over other design options.…”

mentioning

confidence: 99%

“… 18 Silver-selective membranes formulated with a reduced exchange capacity and interrogated under an accumulation/stripping protocol were demonstrated to be responsive at nanomolar concentrations in water samples. 4 , 19 Notably, the thickness of the membrane used in these successful cases was claimed to be crucial to preventing any mass transport limitation on charge carrier rearrangement within the membrane domain: ca. 250 nm.…”

mentioning

confidence: 99%

Spectroelectrochemistry with Ultrathin Ion-Selective Membranes: Three Distinct Ranges for Analytical Sensing

2022

Self Cite

View full text Add to dashboard Cite

We present spectroelectrochemical sensing of the potassium ion (K + ) at three very distinct analytical ranges—nanomolar, micromolar, and millimolar—when using the same ion-selective electrode (ISE) but interrogated under various regimes. The ISE is conceived in the all-solid-state format: an ITO glass modified with the conducting polymer poly(3-octylethiophene) (POT) and an ultrathin potassium-selective membrane. The experimental setup is designed to apply a potential in a three-electrode electrochemical cell with the ISE as the working electrode, while dynamic spectral changes in the POT film are simultaneously registered. The POT film is gradually oxidized to POT + , and this process is ultimately linked to K + transfer at the membrane-sample interface, attending to electroneutrality requirements. The spectroelectrochemistry experiment provides two signals: a voltammetric peak and a transient absorbance response, with the latter of special interest because of its correspondence with the generated charge in the POT and thus with the ionic charge expelled from the membrane. By modifying how the ion analyte (K + but also others) is initially accumulated into the membrane, we found three ranges of response for the absorbance: 10–950 nM for an accumulation-stripping protocol, 0.5–10 μM in diffusion-controlled cyclic voltammetry, and 0.5–32 mM with thin-layer cyclic voltammetry. This wide response range is a unique feature, one that is rare to find for a sensor and indeed for any analytical technique. Accordingly, the developed sensor is highly appealing for many analytical applications, especially considering the versatility of samples and ion analytes that may be spotted.

show abstract

Subnanomolar detection of ions using thin voltammetric membranes with reduced Exchange capacity

Cited by 14 publications

References 37 publications

Solid‐Contact Ion‐Selective Electrodes Paving the Way for Improved Non‐Zero Current Sensors: A Minireview

Solid‐Contact Ion‐Selective Electrodes Paving the Way for Improved Non‐Zero Current Sensors: A Minireview

Potentiometric Sensing

Spectroelectrochemistry with Ultrathin Ion-Selective Membranes: Three Distinct Ranges for Analytical Sensing

Contact Info

Product

Resources

About