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Highlights: [•] A sensor was developed for melamine direct and selective detection in real samples. [•] The sensor displayed a selectivity towards melamine compared with other interferents. [•] The sensor showed a linear relationship between the signal and the melamine concentration. [Copyright &y& Elsevier]

A novel molecular imprinted polymer (MIP) based thermo-sensitive electrochemical sensor was fabricated by an electropolymerization method using N-isopropylacryamide and theophylline as the monomer and the template molecule, respectively. The [Fe(CN)6]3−/[Fe(CN)6]4−was used as an electrochemical probe to investigate the electrochemical behavior of the prepared sensor. The influence factors including electropolymerization cycles, the utilization of cross-linkers, and the extraction solution were investigated in detail. The sensor exhibited excellent thermo-sensitive behavior to environmental temperature stimuli and displayed a good recognition capacity for template molecules from its analogues. This approach may allow the application of this type of intelligent electrochemical sensor for stimulus-responsive recognition of template molecules. [ABSTRACT FROM AUTHOR]

Molecular imprinting and sol-gel technique were combined to develop a molecular imprinted polymer (MIP) based electrochemical sensor in this work. With the successive modification of multi-walled carbon nanotubes (MWNTs) and gold nanoparticles (GNPs), a modified glassy carbon electrode (GCE) was immersed in a sol-gel solution in the presence of paracetamol (PR) for the electropolymerization to fabricate an imprinted sensor. Scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) were employed to characterize the constructed sensor. The factors for the sensor preparation, the electropolymerization potential range, the monomer concentration, and the scan rate for the sensor preparation were optimized. The sensor displayed an excellent recognition capacity toward PR compared with other analogues. Additionally, the DPV peak current was linear to the PR concentration in the range from 8.0 × 10−8to 5.0 × 10−5 mol/L, with a detection limit of 4.0 × 10−8 mol/L. The prepared sensor also showed satisfactory reproducibility and regeneration capacity. [ABSTRACT FROM AUTHOR]

Abstract: A simple and efficient molecularly imprinted polymers (MIPs) based electrochemical sensor were proposed and prepared by electropolymerization of pyrrole in the presence of bovine hemoglobin (BHb) in an aqueous solution. The fabrication process of the sensor was characterized by differential pulse voltammetry and electrochemical impedance spectroscopy, in which [Fe(CN)6]3−/[Fe(CN)6]4− was used as an electrochemical active probe. The influence factors including electropolymerization cycles, scan rate, the concentration of pyrrole, and the extraction conditions were investigated in detailed. Under the optimized conditions, the experimental results showed that the MIPs based sensor possessed a fast rebinding dynamics and an excellent recognition capacity to BHb, compared to the other non-template proteins. Moreover, the prepared sensor also exhibited a dependent relationship between the concentration of template protein and peak current of [Fe(CN)6]3−/[Fe(CN)6]4−. [Copyright &y& Elsevier]