RAMOS PAYÁN , María Dolores

In this study, an electro assisted liquid phase microextraction (EA-LPME) procedure to determine seven parabens (methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and benzyl paraben) and three of their key hydroxy metabolites (4-hydroxy, 3,4-dihydroxy, and 3,4,5-trihydroxy benzoic acid) was optimised in maternal urine and amniotic fluid...

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...

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

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),...

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, a novel solvent-free microfluidic method based liquid phase microextraction has been proposed for the first time. A comprehensive study of liquid phase microextraction (LPME) and electromembrane extraction (EME) implemented in microfluidic formats has been carried out to investigate the efficiency of biodegradable membranes (such...

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...

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...

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...

Liquid-phase microextraction (LPME) in microfluidic devices involves extraction of acids or bases by diffusion in a pH gradient, from aqueous sample, through a supported liquid membrane (SLM), and into aqueous acceptor phase. The SLM is an integrated part of the device, and separates the donor (sample) and acceptor phase channels. In this work,...

Los alumnos deben aprender a aplicar conceptos teóricos en la resolución de problemas analíticos, clave para la innovación docente universitaria. Esta integración teoría-práctica potencia una comprensión profunda y se identificaron deficiencias en la transferencia de conocimiento entre teoría y práctica. Por ello, proponemos innovaciones...

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...

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...

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...

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-...