RAMOS PAYÁN , María Dolores

El objetivo de esta Tesis Doctoral es el estudio y puesta a punto de diferentes metodologías de microextracción que implican el uso de membranas líquidas soportadas (supported liquid membrane, SLM) sobre fibras huecas de polipropileno, y su aplicación a l

This tutorial discusses how to integrate different microextraction procedures into millifluidic platforms and the applicability of such systems for the determination of acidic and basic drugs. Sample preparation techniques have been downscaled into a millifluidic format and the replacement of conventional analytical systems by miniaturized...

Development of green approaches have emerged as a challenge that highlight the pressing need for nontoxic solvents, miniaturized method and bio-degradable materials. In this regard, an environmentally-friendly microfluidic system based on natural deep eutectic solvents (DESs) immobilized in agarose membranes was developed to extract parabens...

Microfluidic devices as sample treatment have showed significant advancements in recent years, becoming an important tool in pharmaceutical analysis. In this work, a green microfluidic method for the simultaneous extraction of basic polar and non-polar compounds is proposed for the first time, offering a new and more sustainable and...

In this work, for the first time, a microchip device integrating liquid-liquid-solid phase microextraction is presented. As a novel approach to microchip systems, liquid-liquid-solid microextraction was performed in a sandwiched microchip device. The microchip device consisted of three poly(methyl methacrylate) layers along with a double...

For the first time, liquid phase microextraction miniaturized into a microfluidic chip device (μLPME) combined with a HPLC procedure using diode array (DAD) has been developed for the determination of four fluoroquinolones: marbofloxacin (MRB), norfloxacin (NRF), ciprofloxacin (CPR) and danofloxacin (DNF). The microfluidic chip consisted of two...

A fast double-flow microfluidic based liquid phase microextraction (DF-µLPME) combined with a HPLC-UV procedure using diode array detection has been developed for the determination of the four most widely used parabens: Ethyl 4-hydroxybenzoate (EtP), Propyl 4-hydroxybenzoate (PrP), Butyl 4-hydroxybenzoate (BuP) and IsoButyl 4-hydroxybenzoate...

In this work, the traditional liquid phase microextraction (LPME) has been miniaturized into a microfluidic device (μLPME) where liquid phase microextraction is combined with an HPLC procedure. This integration enables extraction and determination of acid drugs by μLPME and HPLC, respectively. The analytes selected for the test are five widely...

The simultaneous extraction of acidic and basic compounds is considered a great challenge. In this work, an efficient and fast microfluidic device is described for the simultaneous determination of acidic and basic drugs by two electromembrane extraction, offering extraction efficiencies over 98% for all analytes in human urine samples and...

In this work, hippuric acid (log P = 0.5), anthranilic acid (log P = 1.3), ketoprofen (log P = 3.6), and naproxen (log P = 3.0) were simultaneously extracted by a green microfluidic device based on the principles of liquid-phase microextraction (LPME). Different deep eutectic solvents (DESs) were investigated as supported liquid membrane (SLM),...

Liquid phase microextraction (LPME) into a microfluidic has undergone great advances focused on downscaled and miniaturized devices. In this work, a microfluidic device was developed for the extraction of sulfonamides in order to accelerate the mass transfer and passive diffusion of the analytes from the donor phase to the acceptor phase. The...

Introducing a myriad array of chemicals in different industrial fields has made sample preparation inevitable for trace analysis. Classical extraction techniques such as solid phase extraction (SPE) and liquid-liquid extraction (LLE) techniques often suffer from tedious procedures (huge workload) and hazards to personnel and environment...

Frequent consumption of pharmaceuticals and personal care products (PPCPs) have emerged as a current problem that highlights the pressing need for new multi-residue analytical methods that allow their simultaneous determination to assess their overall effect on human health. In this regard and for the first time, a versatile microfluidic based-...

In liquid-phase microextraction (LPME), the sample and the acceptor are separated by a synthetic organic solvent, which is immobilized in a porous polymeric membrane of polypropylene or polyvinylidene fluoride. The organic solvent serves as extraction phase, while the polymeric membrane serves as support membrane. The combination of extraction...

In sample preparation, simultaneous extraction of analytes of very different polarity from biological matrixes represents a challenge. In this work, verapamil hydrochloride (VRP), amitriptyline (AMP), tyramine (TYR), atenolol (ATN), metopropol (MTP) and nortriptyline (NRP) were used as basic model analytes and simultaneously extracted from...

For thefirst time, a novel and versatile microfluidic device wasdeveloped to achieve the possibility of combining different extraction principlesusing a miniaturized approach for the extraction of different classes of analytes.This novel microchip is composed of a sandwich of three poly(methylmethacrylate) (PMMA) layers. Four channels allowed...

A new geometry for a versatile microfluidic-chip device based liquid phase microextraction was developed in order to enhance the preconcentration in microfluidic chips and also to enable double-flow and stopped-flow working modes. The microchip device was combined with a HPLC procedure for the simultaneous determination of two different...

Sample preparation plays a pivotal role in chemical analysis, serving to isolate target analytes from diverse matrices and enhance measurement selectivity and sensitivity. This review examines microextraction's eco-friendliness versus tradition, focusing on LPME and EME systems for acidic compounds. Different solid supports (polymeric and gel...

A new geometry for a versatile microfluidic-chip device based liquid phase microextraction was developed in order to enhance the preconcentration in microfluidic chips and also to enable double-flow and stopped-flow working modes. The microchip device was combined with a HPLC procedure for the simultaneous determination of two different...

Liquid phase microextraction (LPME) and electromembrane microextraction (EME) can be considered as two of the most popular techniques in sample treatment today. Both techniques can be configurated as membrane-assisted techniques to carry out the extraction. These supports provide the required geometry and stability on the contact surface...

In this work, a microfluidic-chip based system for liquid-phase microextraction (LPME-chip) was developed. Sample solutions were pumped into the LPME-chip with a micro-syringe pump at a flow rate of 3–4 μL min−1. Inside the LPME chip, the sample was in direct contact with a supported liquid membrane (SLM) composed of 0.2 μL dodecyl acetate...

An automated liquid-phase microextraction (LPME) device in a chip format has been developed and coupled directly to high performance liquid chromatography (HPLC). A 10-port 2-position switching valve was used to hyphenate the LPME-chip with the HPLC autosampler, and to collect the extracted analytes, which then were delivered to the HPLC...

In this work, we investigated for the first time hydrophobic deep eutectic solvents (DES) as supported liquid membrane (SLM) for electromembrane extraction (EME). Camphor, coumarin, DL-menthol, and thymol were used as non-ionic DES components. Different DESs compositions were tested, to study systematically the importance of hydrogen bonding...

The paper describes a comprehensive study of the importance of cations to improve the efficiency and mass transfer in the electromembrane extraction for the determination of non-steroidal antiinflammatory. The procedure has been demonstrated to be adequate for the analysis of the selected non-steroidal anti-inflammatory drugs in human urine...