Deiene Garcia Mutio | University of the Basque Country, Euskal Herriko Unibertsitatea (original) (raw)

Papers by Deiene Garcia Mutio

Research paper thumbnail of Solid-phase synthesis of imprinted nanoparticles grafted on gold substrates for voltammetric sensing of 4-ethylphenol

Sensors and Actuators B: Chemical, 2016

Highlights-Imprinted nanoparticles for 4-ethylphenol synthesised by solid-phase imprinting.-Impri... more Highlights-Imprinted nanoparticles for 4-ethylphenol synthesised by solid-phase imprinting.-Imprinted nanoparticles are used as recognition elements in voltammetric sensors.-Gold electrode modification was followed by EIS and CV.-MIP nanoparticles favoured 4-ethylphenol determination by DPV.-The MIN-based sensor showed excellent selectivity for the target compound.

Research paper thumbnail of Molecularly imprinted nanoparticles grafted to porous silica as chiral selectors in liquid chromatography

Journal of chromatography. A, Jan 28, 2017

The work presented here explores the grafting of molecularly imprinted nanoparticles (MIN) on sil... more The work presented here explores the grafting of molecularly imprinted nanoparticles (MIN) on silica beads for the development of new chiral stationary phases (CSP). Both solid-phase imprinting and precipitation polymerisation were tested for MIN synthesis though the latter approach was the only one that provided efficient chiral selectors. MIN particles were prepared by iniferter polymerisation initiated by UV radiation, using itaconic acid as functional monomer and ethylene dimethacrylate as cross-linker. This resulted in particles with an average size of 249.0±4.0nm which were covalently immobilised onto chromatographic silica beads. The resultant CSP based on the composite silica beads-MIN was capable of resolving the racemate of the antidepressant drug citalopram and also separating its major metabolites by liquid chromatography, with better efficiency and peak symmetry than other MIP based CSP. The methodology presented here allowed for the quantification of the pharmacologica...

Research paper thumbnail of Molecularly Imprinted High Affinity Nanoparticles for 4-Ethylphenol Sensing

Procedia Engineering, 2015

A novel sensor for 4-ethylphenol (4EP) was developed based on molecularly imprinted nanoparticles... more A novel sensor for 4-ethylphenol (4EP) was developed based on molecularly imprinted nanoparticles produced via the solid phase imprinting method. The nanoparticles were immobilised on the surface of a gold electrode previously modified with a self assembled monolayer of lipoic acid coupled to EDC/NHS ((1-ethyl-3-[dimethylaminopropyl]carbodiimide)/Nhydroxysuccinimide). Each step of the process was characterised by electrochemical impedance spectroscopy and cyclic voltammetry. The electrode was used to selectively determine 4EP by differential pulse voltammetry; a quite remarkable sensitivity improvement was observed in the nanoparticle-modified electrode in reference to the non modified bare gold electrode.

Research paper thumbnail of Controlled grafting of molecularly imprinted films on gold microelectrodes using a self-assembled thiol iniferter

Electrochimica Acta, 2018

Herein, a straightforward approach for the controlled coating of gold microelectrodes with molecu... more Herein, a straightforward approach for the controlled coating of gold microelectrodes with molecularly imprinted polymer (MIP) thin films is presented. To this end, a new iniferter has been synthesised, 3mercaptopropyl diethylcarbamodithioate, which contains terminal thiol groups capable of forming self-assembled monolayers (SAM) on gold substrates. The iniferter SAM was activated under UV radiation after the immersion of the microelectrode in the polymerisation solution, containing 4-ethylphenol (4EP) as template and 4-vinylpyridine and ethylene dimethacrylate as functional monomer and crosslinker respectively. The voltammetric behaviour of the resulting MIP-coated microsensor was assessed next, finding that electrochemical response was linear to the concentration of the target analyte (4EP) in a range comprised between 10 À6 and 10 À3 mol L À1 , showing a sensitivity of 1.02 ± 0.02 (nA L mmol À1) (R 2 : 0.9983). Measurement repeatability was also evaluated performing a series of measurements with the same sensor at two concentrations levels of 4EP, 5 Â 10 À6 mol L À1 and 10 À4 mol L À1 , obtaining relative standard deviations (RSD) of 3.41% and 1.92% respectively. Similarly, sensor-to-sensor repeatability was also determined obtaining RSD values of 10.02% and 16.97% respectively. Sensor selectivity was finally studied comparing the peak current intensity of 4EP with current intensities registered with structural analogues. It was found that sensor was capable of discriminating the target compound from structural analogues presenting remarkable selectivity, even for almost identical compounds such as 4-vinylphenol.

Research paper thumbnail of Solid-phase synthesis of imprinted nanoparticles grafted on gold substrates for voltammetric sensing of 4-ethylphenol

Sensors and Actuators B: Chemical, 2016

Highlights-Imprinted nanoparticles for 4-ethylphenol synthesised by solid-phase imprinting.-Impri... more Highlights-Imprinted nanoparticles for 4-ethylphenol synthesised by solid-phase imprinting.-Imprinted nanoparticles are used as recognition elements in voltammetric sensors.-Gold electrode modification was followed by EIS and CV.-MIP nanoparticles favoured 4-ethylphenol determination by DPV.-The MIN-based sensor showed excellent selectivity for the target compound.

Research paper thumbnail of Molecularly imprinted nanoparticles grafted to porous silica as chiral selectors in liquid chromatography

Journal of chromatography. A, Jan 28, 2017

The work presented here explores the grafting of molecularly imprinted nanoparticles (MIN) on sil... more The work presented here explores the grafting of molecularly imprinted nanoparticles (MIN) on silica beads for the development of new chiral stationary phases (CSP). Both solid-phase imprinting and precipitation polymerisation were tested for MIN synthesis though the latter approach was the only one that provided efficient chiral selectors. MIN particles were prepared by iniferter polymerisation initiated by UV radiation, using itaconic acid as functional monomer and ethylene dimethacrylate as cross-linker. This resulted in particles with an average size of 249.0±4.0nm which were covalently immobilised onto chromatographic silica beads. The resultant CSP based on the composite silica beads-MIN was capable of resolving the racemate of the antidepressant drug citalopram and also separating its major metabolites by liquid chromatography, with better efficiency and peak symmetry than other MIP based CSP. The methodology presented here allowed for the quantification of the pharmacologica...

Research paper thumbnail of Molecularly Imprinted High Affinity Nanoparticles for 4-Ethylphenol Sensing

Procedia Engineering, 2015

A novel sensor for 4-ethylphenol (4EP) was developed based on molecularly imprinted nanoparticles... more A novel sensor for 4-ethylphenol (4EP) was developed based on molecularly imprinted nanoparticles produced via the solid phase imprinting method. The nanoparticles were immobilised on the surface of a gold electrode previously modified with a self assembled monolayer of lipoic acid coupled to EDC/NHS ((1-ethyl-3-[dimethylaminopropyl]carbodiimide)/Nhydroxysuccinimide). Each step of the process was characterised by electrochemical impedance spectroscopy and cyclic voltammetry. The electrode was used to selectively determine 4EP by differential pulse voltammetry; a quite remarkable sensitivity improvement was observed in the nanoparticle-modified electrode in reference to the non modified bare gold electrode.

Research paper thumbnail of Controlled grafting of molecularly imprinted films on gold microelectrodes using a self-assembled thiol iniferter

Electrochimica Acta, 2018

Herein, a straightforward approach for the controlled coating of gold microelectrodes with molecu... more Herein, a straightforward approach for the controlled coating of gold microelectrodes with molecularly imprinted polymer (MIP) thin films is presented. To this end, a new iniferter has been synthesised, 3mercaptopropyl diethylcarbamodithioate, which contains terminal thiol groups capable of forming self-assembled monolayers (SAM) on gold substrates. The iniferter SAM was activated under UV radiation after the immersion of the microelectrode in the polymerisation solution, containing 4-ethylphenol (4EP) as template and 4-vinylpyridine and ethylene dimethacrylate as functional monomer and crosslinker respectively. The voltammetric behaviour of the resulting MIP-coated microsensor was assessed next, finding that electrochemical response was linear to the concentration of the target analyte (4EP) in a range comprised between 10 À6 and 10 À3 mol L À1 , showing a sensitivity of 1.02 ± 0.02 (nA L mmol À1) (R 2 : 0.9983). Measurement repeatability was also evaluated performing a series of measurements with the same sensor at two concentrations levels of 4EP, 5 Â 10 À6 mol L À1 and 10 À4 mol L À1 , obtaining relative standard deviations (RSD) of 3.41% and 1.92% respectively. Similarly, sensor-to-sensor repeatability was also determined obtaining RSD values of 10.02% and 16.97% respectively. Sensor selectivity was finally studied comparing the peak current intensity of 4EP with current intensities registered with structural analogues. It was found that sensor was capable of discriminating the target compound from structural analogues presenting remarkable selectivity, even for almost identical compounds such as 4-vinylphenol.