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We report here the synthesis and characterisation of ion imprinted polymers nanoparticles (nanoIIPs) and their application as electrochemical sensors for Cu2+ ions determination. Imprinted nanoparticles were developed following a free radical polymerisation in water and subsequently immobilised on the surface of gold screen printed electrodes (SPAuE). Characterisation of nanoIIPs was performed using dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Electrochemical determination of Cu2+ was achieved in water samples using differential pulse voltammetry (DPV). Voltammetric responses demonstrate different current responses for copper(II)‐imprinted polymers nanoparticles (Cu‐nanoIIPs) and non‐imprinted polymer nanoparticles. The nanoIIPs sensor responds to copper (II) in a linear range between 1.9 and 61 nM, with a sensitivity of 0.0618 μA nM−1. The limit of detection (LOD) and limit of quantification (LOQ) of the electrochemical sensor tested in buffer solution were 74 pM and 247 pM, respectively. Furthermore, the sensor presents high selectivity when tested against other ions such as Ni2+, Zn2+, NO3−, and CrO42−, and it is potentially suitable for environmental monitoring of heavy metals and food control. The sensor responses were also successfully evaluated in spiked commercialised drinking water. [ABSTRACT FROM AUTHOR]

Caffeic acid (CA), a member of the hydroxycinnamic acid family, has garnered attention in the medical community for its wide‐ranging health benefits. However, its application in pharmaceutical and nutraceutical products has been hampered by its distinctly bitter taste, which deters many consumers. This study investigates the taste‐masking of caffeic acid (CA) using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD). A CA micro‐conductometric sensor was developed. This advanced technology demonstrated remarkable sensitivity, capable of detecting CA at concentrations as low as 10−5 M, with a rapid response time between 10 and 50 seconds. The binding constant of the CA‐HP‐β‐CD complex was determined to be 240±24. 1H NMR spectroscopy analysis provided concrete evidence of the formation of a 1 : 1 inclusion complex between CA and HP‐β‐CD. These findings collectively suggest that HP‐β‐CD is highly effective in masking CA's bitterness, thereby significantly enhancing its palatability. [ABSTRACT FROM AUTHOR]

The adsorption of amino-functionalized poly(methyl methacrylate) particles prepared by emulsion polymerization onto polyamide/elastane fibres was investigated. The influence of several physicochemical parameters (pH, ionic strength) on the colloidal stability and surface properties of the cationic latex particles was first examined. Then, particle adsorption was studied as a function of particle concentration, particle size, time, pH and salinity. The results obtained demonstrated that the adsorption process was mainly governed by electrostatic interactions and the adsorption isotherms were analysed on the basis of a Langmuir model. Finally, the effect of washing steps on the adsorbed particles was investigated. The results obtained indicated strong interactions between particles and textile fibres. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]