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Fernando Benito-Lopez

Fernando Benito-Lopez
CIC microGUNE · Microfluidics Unit

PhD

About

166
Publications
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3,400
Citations

Publications

Publications (166)
Article
Full-text available
A portable, wireless system capable of in situ reagent-based colorimetric analysis is demonstrated. The system is based on a reconfigurable low cost optical detection method employing a paired emitter detector diode device, which allows a wide range of centrifugal microfluidic layouts to be implemented. Due to the wireless communication, acquisitio...
Article
This work presents the fabrication, characterisation and the performance of a wearable, robust, flexible and disposable chemical barcode device based on a micro-fluidic platform that incorporates ionic liquid polymer gels (ionogels). The device has been applied to the monitoring of the pH of sweat in real time during an exercise period. The device...
Article
Full-text available
In this work the development of an autonomous, robust and wearable micro-fluidic platform capable of performing on-line analysis of pH in sweat is discussed. Through the means of an optical detection system based on a surface mount light emitting diode (SMD LED) and a light photo sensor as a detector, a wearable system was achieved in which real-ti...
Article
Full-text available
In this paper we present a microfluidic device that has integrated pH optical sensing capabilities based on polyaniline. The optical properties of polyaniline coatings change in response to the pH of the solution that is flushed inside the microchannel offering the possibility of monitoring pH in continuous flow over a wide pH range throughout the...
Article
Full-text available
Additive manufacturing technology is an emerging method for rapid prototyping, which enables the creation of complex geometries by one-step fabrication processes through a layer-by-layer approach. The simplified fabrication achieved with this methodology opens the way towards a more efficient industrial production, with applications in a great numb...
Article
Full-text available
Optical fiber-based Localized Surface Plasmon Resonance (OF-LSPR) biosensors have emerged as an ultra-sensitive miniaturized tool for a great variety of applications. Their fabrication by the chemical immobilization of gold nanoparticles (AuNPs) on the optic fiber end face is a simple and versatile method. However, it can render poor reproducibilit...
Article
Full-text available
Remote manipulation of superhydrophobic surfaces provides fascinating features in water interface-related applications. A superhydrophobic magnetic nanoparticle colloid layer is able to float on the water-air interface and form a stable water-solid-air interface due to its inherent water repulsion, buoyancy, and lateral capillarity properties. More...
Article
Nowadays, miniaturization and portability are crucial characteristics that need to be considered for the development of water monitoring systems. In particular, the use of handheld technology, including microfluidics, is exponentially expanding due to its versatility, reduction of reagents and minimization of waste, fast analysis times and portabil...
Article
Low cost and user-friendly paper microfluidic devices, combined with DNA-based biosensors with binding capacities for specific molecules, have been proposed for the developing of novel platforms that ease and speed-up the process of cell secretion monitoring. In this work, we present the first cellulose microfluidic paper-based analytical device fo...
Article
The accumulation and deposition of undesired air bubbles on the surface of microfluidic channels and on underwater functional systems is a major drawback, which worsen their performance. Present de-bubbling strategies...
Article
Biocompatible magnetic hydrogels provide a great source of synthetic materials, which facilitate remote stimuli, enabling safer biological and environmental applications. Prominently, the ex situ and in situ magnetic phase integration are used to fabricate magneto-driven hydrogels, exhibiting varied behaviours in aqueous media. Therefore, it is ess...
Article
Full-text available
Lactate is present in sweat at high concentrations, being a metabolite of high interest in sport science and medicine. Therefore, the potential to determine lactate concentrations in physiological fluids, at the point of need with minimal invasiveness, is very valuable. In this work, the synthesis and performance of an alginate bead biosystem was i...
Article
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The manipulation of droplets via a magnetic field forms the basis of a fascinating technology that is currently in development. Often, the movement of droplets with magnets involves adding magnetic particles in or around the droplet; alternatively, magneto responsive surfaces may also be used. This work, presents and characterizes experimentally th...
Article
Full-text available
Droplet Manipulation In article number 2100178, Fernando Benito-Lopez, Lourdes Basabe-Desmonts, and Vahid Nasirimarekani show that the interaction between an oil-based ferrofluid and a drop of water results in the formation of a ferrofluid ring around the drop of water. The ring behaves like a soft matter dipole, disappearing once the magnetic fiel...
Article
Full-text available
Versatile sensing matrixes are essential for the development of enzyme-immobilized optical biosensors. A novel three-dimensional titanium dioxide nanotubes/alginate hydrogel scaffold is proposed for the detection of sweat biomarkers, lactate, and glucose in artificial sweat. Hydrothermally synthesized titanium dioxide nanotubes were introduced to t...
Article
Non-invasive collection of target cells is crucial for research in biology and medicine. In this work, we combine a thermo-responsive material, poly(N-isopropylacrylamide), with an electroactive material, poly(3,4-ethylene-dioxythiopene):poly(styrene sulfonate), to generate a smart and conductive copolymer for the label-free and non-invasive detect...
Article
The effect of cell‐cell contact on gene transfection is mainly unknown. Usually, transfection is carried out in batch cell cultures without control over cellular interactions, and efficiency analysis relies on complex and expensive protocols commonly involving flow cytometry as the final analytical step. Novel platforms and cell patterning are bein...
Article
A microfluidic, label-free optical sensor for water pollutants, which is based on a packed micro-column of microspheres with refractive index similar to that of water, is presented. The perfluoropolyether microspheres are synthetized by membrane emulsification followed by UV irradiation. The microfluidic channel hosting the packed column is transpa...
Article
Water quality monitoring of drinking, waste, fresh and, seawaters is of great importance to ensure safety and wellbeing for humans, fauna and, flora. Researchers are developing robust water monitoring microfluidic devices but, the delivery of a cost-effective, commercially available platform has not yet been achieved. Conventional water monitoring...
Article
Full-text available
The main problem for the expansion of the use of microfluidic paper-based analytical devices and, thus, their mass production is their inherent lack of fluid flow control due to its uncontrolled fabrication protocols. To address this issue, the first step is the generation of uniform and reliable microfluidic channels. The most common paper microfl...
Article
Microfluidic microsystems are often designed to analyze samples of small volumes of fluids; however, some applications require the analysis of larger volumes. The ideal miniaturized microfluidic analytical device should be autonomous and capable of integrating all the required functions within a single fluidic network. While a number of self-powere...
Article
Full-text available
In vitro cytotoxicity testing is essential in the pharmaceutical and environmental industry to study the effects of potential harmful compounds for human health. Classical assays present several disadvantages: they are commonly based on live-death labelling, are highly time consuming and/or require skilled personnel to be performed. The current tre...
Article
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Lipid membrane nanotubes (NTs) are a widespread template for in vitro studies of cellular processes happening at high membrane curvature. Traditionally NTs are manufactured one by one, using sophisticated membrane micromanipulations, while simplified methods for controlled batch production of NTs are in growing demand. Here we propose a lab-on-a-ch...
Article
Full-text available
Low cost easy to use cell viability tests are needed in the pharmaceutical, biomaterial and environmental industry to measure adverse cellular effects. We present a new methodology to track cell death with high resolution. Adherent cells commonly detach from the surface when they die. However some toxic compounds promote adhesion of dead cells. A m...
Article
Nowadays, there are strong efforts in developing new technology for rapid detection of specific DNA sequences for environmental monitoring, forensic analysis and rapid biomedical diagnosis applications. That is where microfluidic paper-based analytical devices are positioned as suitable platforms for the development of point of care analytical devi...
Article
Full-text available
The facet of optical fibers coated with nanostructures enable the development of ultraminiature and sensitive (bio)chemical sensors. The reported sensors until now lack of specificity and the fabrication methods offer poor reproducibility. Here, we demonstrate that by transforming the facet of conventional multimode optical fibers onto plasmon reso...
Article
Full-text available
The high sensitivity of silicon microcantilever sensors has expanded their use in areas ranging from gas sensing to bio-medical applications. Photochromic molecules also represent promising candidates for a large variety of sensing applications. In this work, the operating principles of these two sensing methods are combined in order to detect the...
Article
In the search of biomaterials that promote cell adhesion, it is crucial to explore the integrin-substrate dynamic interactions given in a certain cell type to design successful biofunctionalization strategies. Here, we use a microarray platform for a thorough characterization of cell adhesion to a particular substrate. A biosensor based on an array...
Article
Full-text available
A combination of atomic layer deposition and photolithography is applied to fabricate interdigitated electrodes of aluminum‐doped zinc oxide embedded in polyethylene terephthalate substrates. Various designs with different gap to widths ratios are realized and important characteristics of the electrodes, including thickness, surface roughness, and...
Article
Paper microfluidics technology requires effective handling and control of fluids, and this remains as a significant obstacle for their accessibility by end-users, inhibiting their transition from the laboratory into the market. Here, the synthesis, characterisation and performance as negative passive pumps of cholinium based poly(ionic liquid) hydr...
Article
Full-text available
Micro-capillaries, capable of light-regulated binding and qualitative detection of divalent metal ions in continuous flow, have been realised through functionalisation with spiropyran photochromic brush-type coatings. Upon irradiation with UV light, the coating switches from the passive non-binding spiropyran form to the active merocyanine form, wh...
Article
Herein, we present the synthesis of linear photochromic norbornene polymers bearing spiropyran side groups (poly(SP-R)), and their assembly into LbL films on glass substrates when converted to the poly(MC-R) under UV irradiation. The LbL films were composed of bilayers of poly(allylamine hydrochloride) (PAH) and poly(MC-R), forming (PAH/poly(MC-R))...
Article
While the microfluidic device itself may be small, often the equipment required to control fluidics in the chip unit is large e.g. pumps, valves and mixing units, which can severely limit practical use and functional scalability. In addition, components associated with fluidic control of the device, more specifically the valves and pumps, contribut...
Article
This paper describes the design, fabrication and performance of a reusable ionogel-based photo-actuator, in-situ photopolymerised into a lab-on-a-disc microfluidic device, for flow control. The ionogel provides an effective barrier to liquids during storage of reagents and spinning of the disc. A simple LED (white light) triggers actuation of the i...
Article
Paper-based analytical devices introduce an innovative platform technology for fluid handling and analysis, with wide range of applications, promoting low cost, ease of fabrication/operation and equipment independence. This review gives a general overview on the fabrication techniques reported to date, revealing and discussing their weak points as...
Chapter
Ionic liquids provide ion-rich media, which can control the system properties based on the size, charge, and shape of the ions. Owing to the versatility in their architecture, they can offer rare opportunities for designing smart materials which respond to external signals for specific applications. Polymerizing the ionic liquids can subtly arrange...
Article
Full-text available
A great breadth of questions remains in cellular biology. Some questions cannot be answered using traditional analytical techniques and so demand the development of new tools for research. In the near future, the development of highly integrated microfluidic analytical platforms will enable the acquisition of unknown biological data. These microflu...
Article
In this study we report the synthesis, characterisation and performance of thermo-responsive crosslinked tributylhexyl phosphonium sulfopropylacrylate (PSPA) poly(ionic liquid) (PILc) hydrogels as temperature controlled actuators in microfluidic devices. The hydrogel size is modulated by localised changes in its temperature due to the lower critica...
Article
Herein we investigate the feasibility of detecting photo-induced surface stress changes using the deflection response of cantilevers. For this purpose, silicon microcantilevers have been functionalised with spiropyran photochromic molecules, using both a monolayer and a polymeric brushes approach. Upon ultraviolet light irradiation, the spiropyran...
Article
Microfluidic devices are poised to dramatically influence the future of the process industry. Therefore the understanding and proper evaluation of the flow and mixing behaviour at microscale becomes a very important issue. In this study, the diffusion behaviour of two reacting solutions of HCl and NaOH were directly observed in a glass/polydimethyl...
Article
Full-text available
This study focuses on improving the speed of actuation of poly(N-isopropylacrylamide)-based photoresponsive gels containing copolymerised spiropyran as the photoswitch and acrylic acid as the proton source. The improvement is realised by introducing pores into the material. For this purpose, polyethylene glycol (PEG) of two molecular weights (2000...
Chapter
The possibility of using photo-stimulus to control flow in microfluidics devices is very appealing as light can provide contactless stimulation, is biocompatible and can be applied in a non-invasive and highly precise manner. One of the most popular ways to achieve photo-control flow in microfluidic channels is throughout the use of photo-responsiv...
Conference Paper
Self-powered microfluidics is an emerging field of special interest in the field of rapid analysis. In this line we are witnessing the development of paper and capillary driven microfluidics. A new type of system in on the rise, degas driven flow microfluidics. We report the development of disposable place and play (PnP) micropumps with high flow....
Chapter
Wearable chemical and biochemical sensors are a relatively new area of sensor research that poses unique challenges to the field of wearable sensing. The reason is that chemical sensors have a different mode of operation compared to physical transducers, and thus must be directly exposed, and interact with, specific molecular components in (usually...
Article
A study was conducted to demonstrate the first example of photo-driven chemopropulsion in which photo irradiation in close proximity to the micro-vehicle, a lipophilic droplet initiated a rapid pH change in the aqueous channel fluid in which the vehicle sat, as a result of the photo-induced dissociation of a water soluble organic acid. This led to...
Article
Full-text available
This paper reports for the first time the use of a cross-linked poly(N-isopropylacrylamide) ionogel encapsulating the ionic liquid 1-ethyl-3-methylimidazolium ethyl sulphate as a thermoresponsive and modular microfluidic valve. The ionogel presents superior actuation behaviour to its equivalent hydrogel. Ionogel swelling and shrinking mechanisms an...
Data
Full-text available
Photolithography set-up and photomasks used for fabrication of ionogel microstructures, contact angle results, details of ionogel microstructures, SEM of ionogels, experimental kinetics curves of ionogel swelling and shrinking, images of ionogel microstructures after swelling and shrinking.
Article
Full-text available
This paper presents an extended study on the ion effects of a series of biocompatible hydrated choline based ionic liquids (ILs) on lactate oxidase (LOx), an important enzyme in biosensing technology for the in vitro detection of lactic acid. Secondary structural analysis revealed changes in the protein conformation in hydrated ILs, while thermal u...
Article
Full-text available
Here we describe, for the first time, intriguing solvato-morphological control of spiropyran-based microcrystalline structures. These microstructures exhibit reversible photoisomerization upon light irradiation (UV/Vis) in the solid-state. Finally, light-guided aggregation of these microstructures at the liquid/air interface is also demonstrated.
Data
Full-text available
Microfluidics is advantageous for immunoassay processing (e.g., reducing immunoreagent consumption/assay times) [1], but the fact that most clinically relevant bioassays are developed for well-plate technologies poses significant challenges for integration within μTAS platforms. Assays developed for 96-well plates must be downscaled and adapted for...
Data
Full-text available
Electronic Supplement Information including: Scheme of CMAS platform components, CMAS Graphical User Interface, Griess Reaction Scheme, First generation PEDD system versus CMAS, UV-Vis spectra, Repeatability of PEDD measurements. Kinetic Study and CMAS cost breakdown.
Data
Video File of CMAS in action. Check it out!
Article
Full-text available
Up to now, photoresponsive hydrogels and ionogels based on poly(N-isopropylacrylamide) copolymerised with pendant spiropyran groups require exposure to external acidic solution (usually milimolar HCl) to generate the swollen gel prior to photo-triggered contraction. This serious functional limitation has been solved by copolymerising acrylic acid i...
Article
Here we present a fast and cheap prototyping technique for the realisation of paper-based microfluidic devices simply by using a stamp and indelible ink. The proposed mechanism involves contact stamping of indelible ink to laboratory filter paper using a PDMS stamp, which defines the microfluidic structure. It is a cleanroom and washing steps-free...
Conference Paper
The photo-patterning of photoresponsive N-isopropylacrylamide based ionogel microstructures is investigated. The ionogels are synthesised using phosphonium based room temperature ionic liquids together with a photochromic compound benzospiropyran. These stimuli responsive materials can be actuated simply by using light irradiation, facilitating non...