Development of Electrochemical Platform Based on Molecularly Imprinted Poly(methacrylic acid) Grafted on Iniferter‐modified Carbon Nanotubes for 17β‐Estradiol Determination in Water Samples

Abstract

This paper describes the development of a new electrochemical sensor for 17β‐estradiol (E2) determination based on glassy carbon electrode (GCE) modified with molecularly imprinted polymer grafted onto iniferter‐multiwall carbon nanotubes surface (MIP‐MWCNT) and dihexadecyl‐hydrogen‐phosphate (DHP). The electrochemical method was based on closed‐circuit preconcentration of E2 in 0.1 mol L−1 phosphate buffer (pH 7.0) during 500 s. Upon preconcentration, E2 was determined by differential pulse voltammetry (DPV) exhibiting a limit of detection of 0.01 μmol L−1. The sensor exhibited higher selectivity toward E2 and it was applied for E2 determination in natural water samples, with accuracy attested by HPLC‐DAD.

Development of a Novel Molecularly Imprinted Polyvinylimidazole/Functionalized Carbon Black Nanocomposite‐based Paste Electrode for Electrochemical Sensing of Imazethapyr in Rice Samples

“…Similar results were obtained in other works reported in the literature [30, 45]. With the insertion of MIP in both CB and fCB paste electrodes the R ct (10930 and 341 Ω, respectively), increases about 1.5 fold due to the insulating properties of the MIP [40]. With regard the electroactive area (Ae) obtained by the Randles‐Sevcik equation, fCB presented higher Ae than CB (0.064 and 0.056 cm 2 , respectively) and the presence of MIP diminishes the Ae in 0.059 cm 2 for MIP‐fCB and 0.054 cm 2 for MIP‐CB.…”

“…Electron Impedance Spectroscopy (EIS) was carried out by using 1 mmol L −1 of Fe(CN) 6 3−/4− redox probe in 0.1 mol L −1 of KCl in the frequency range of 0.1 Hz to 100 kHz with and a.c. signal amplitude of 10 mV. The fitting of the spectra to equivalent theoretical circuits was made using the EIS Spectrum Analyzer 1.0 software [40]. The electroactive area of the electrodes was estimated by applying the Randles‐Sevcik equation (Equation 1) [41].…”

Disposable Saliva Sensors for Early Cancer Diagnosis Using Hyper-Cross-Linked Molecularly Imprinted Polymeric Electrocatalysts

“…Pristine PMA2TA reveals the highest charge transfer resistance (R ct = 3515 Ω), primarily due to its nonconductive nature and limited electron-transfer interactions at the electrode−electrolyte interface. 21 In the case of PMA2TA@g-C 3 N 4 , the inclusion of g-C 3 N 4 nanosheets decreases the R ct to 2426 Ω, which not only signifies the impact of conductive g-C 3 N 4 on its electrochemical properties but also validates its preparation. Spermine-imprinted analogues, on the other hand, show substantially reduced R ct values, i.e., 245 and 69 Ω for sPMA2TA and sPMA2TA@g-C 3 N 4 , respectively.…”

Development of a bio‐inspired magnetic nanocomposite synthesized through semi‐covalent imprinting for electrochemical determination of cholesterol in water samples

“…In this sense, studies with a focus on molecularly imprinted polymers-based voltammetric sensors for CHO have been increasingly reported [20]. These materials have gained notable attention due to their high selectivity, cost-effectiveness, mechanical robustness, and chemical inertness [21][22][23].…”