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Protein crystallization still remains mostly an empirical science, as the production of crystals with the required quality for X-ray analysis is dependent on the intensive screening of the best protein crystallization and crystal’s derivatization conditions. Herein, this demanding step was addressed by the development of a high-throughput and low-budget microfluidic platform consisting of an ion exchange membrane (117 Nafion® membrane) sandwiched between a channel layer (stripping phase compartment) and a wells layer (feed phase compartment) forming 75 independent micro-contactors. This microfluidic device allows for a simultaneous and independent screening of multiple protein crystallization and crystal derivatization conditions, using Hen Egg White Lysozyme (HEWL) as the model protein and Hg2+ as the derivatizing agent. This microdevice offers well-regulated crystallization and subsequent crystal derivatization processes based on the controlled transport of water and ions provided by the 117 Nafion® membrane. Diffusion coefficients of water and the derivatizing agent (Hg2+) were evaluated, showing the positive influence of the protein drop volume on the number of crystals and crystal size. This microfluidic system allowed for crystals with good structural stability and high X-ray diffraction quality and, thus, it is regarded as an efficient tool that may contribute to the enhancement of the proteins’ crystals structural resolution.
M. Polino; H. Rho; M. Pina; R. Mallada; A. Carvalho; M. Romão; Isabel Coelhoso; J. Gardeniers; J. Crespo; Carla Portugal. Protein Crystallization in a Microfluidic Contactor with Nafion®117 Membranes. Membranes 2021, 11, 549 .
AMA StyleM. Polino, H. Rho, M. Pina, R. Mallada, A. Carvalho, M. Romão, Isabel Coelhoso, J. Gardeniers, J. Crespo, Carla Portugal. Protein Crystallization in a Microfluidic Contactor with Nafion®117 Membranes. Membranes. 2021; 11 (8):549.
Chicago/Turabian StyleM. Polino; H. Rho; M. Pina; R. Mallada; A. Carvalho; M. Romão; Isabel Coelhoso; J. Gardeniers; J. Crespo; Carla Portugal. 2021. "Protein Crystallization in a Microfluidic Contactor with Nafion®117 Membranes." Membranes 11, no. 8: 549.
Surface-enhanced Raman scattering (SERS) is a powerful spectroscopic technique for selective detection and quantification of molecules at extremely low concentrations. However, practical SERS applications for gaseous chemicals with small cross section is still in its early stages. We herein report a plasmonic-sorbent thin-film platform with integrated Raman internal standard with outstanding SERS sensing capabilities for chemical warfare agents (CWA) simulants. The thin film is constituted of close-packed core–shell [email protected] nanorods individually encapsulated within a ZIF-8 framework ([email protected]@ZIF-8). While the [email protected] nanoparticles amplify the Raman signal of molecules located near their surface, the ZIF-8 framework plays a key role in the trapping of the dimethyl methylphosphonate (DMMP) or 2-chloroethyl ethyl sulfide (CEES) from the gas phase as well as Raman internal standard. The underlying adsorption mechanism of the molecules within the ZIF-8 framework as well as the interaction between DMMP and Ag surface are investigated by computational simulations. Outstanding SERS sensing capabilities of [email protected]@ZIF-8 thin films, in terms of response time, quantification limit, reproducibility, and recyclability, are demonstrated for dimethyl methylphosphonate (DMMP) and 2-chloroethyl ethyl sulfide (CEES), selected as CWA simulants of sarin gas and mustard gas, respectively. A limit of detection (LOD) of 0.2 ppbV is reported for DMMP. Additionally, experiments performed with portable Raman equipment detect 2.5 ppmV for DMMP in ambient air and 76 ppbV for CEES in N2, with response times of 21 and 54 s, respectively. This proof of concept opens the door for handheld SERS-based gas sensing at ultralow concentrations in practical applications, such as homeland security, critical infrastructure protection, chemical process monitoring, or personalized medicine.
Marta Lafuente; Sarah De Marchi; Miguel Urbiztondo; Isabel Pastoriza-Santos; Ignacio Pérez-Juste; Jesús Santamaría; Reyes Mallada; María Pina. Plasmonic MOF Thin Films with Raman Internal Standard for Fast and Ultrasensitive SERS Detection of Chemical Warfare Agents in Ambient Air. ACS Sensors 2021, 6, 2241 -2251.
AMA StyleMarta Lafuente, Sarah De Marchi, Miguel Urbiztondo, Isabel Pastoriza-Santos, Ignacio Pérez-Juste, Jesús Santamaría, Reyes Mallada, María Pina. Plasmonic MOF Thin Films with Raman Internal Standard for Fast and Ultrasensitive SERS Detection of Chemical Warfare Agents in Ambient Air. ACS Sensors. 2021; 6 (6):2241-2251.
Chicago/Turabian StyleMarta Lafuente; Sarah De Marchi; Miguel Urbiztondo; Isabel Pastoriza-Santos; Ignacio Pérez-Juste; Jesús Santamaría; Reyes Mallada; María Pina. 2021. "Plasmonic MOF Thin Films with Raman Internal Standard for Fast and Ultrasensitive SERS Detection of Chemical Warfare Agents in Ambient Air." ACS Sensors 6, no. 6: 2241-2251.
In this work, alveolar‐like microfluidic devices are studied with a horizontal membrane arrangement that demonstrate a great potential as small‐scale blood oxygenator. The design criteria for the fabricated devices are to maximize the oxygen saturation level and minimize liquid chamber volume while ensuring the physiological blood flow in order to avoid thrombus formation and channel blockage during operation. The liquid chamber architecture is iteratively modified upon analysis of the fluid dynamics by computer modeling. Accordingly, two alveolar type architectures are fabricated, Alveolar Design 1 (AD1) and Alveolar Design 2 (AD2), and evaluated for oxygenation of sheep blood. The attained O2 transfer rate at 1 mL min−1 of blood flow rate for both devices is rather similar: 123 and 127 mL min−1 m−2 for AD1 and AD2 microfluidic devices, respectively. Among the studied, AD2 type geometry would lead to the lowest pressure drop and shear stress value upon implementation in a scaled microfluidic artificial lung (μAL) to satisfy oxygenation requirements of a 2.0 kg neonate.
Magdalena Malankowska; Ismael Pellejero; Ignacio Julian; Hoon Suk Rho; Pedro Pinczowski; Roald M. Tiggelaar; Han Gardeniers; Reyes Mallada; Maria Pilar Pina. On the Improvement of Alveolar‐Like Microfluidic Devices for Efficient Blood Oxygenation. Advanced Materials Technologies 2021, 6, 2001027 .
AMA StyleMagdalena Malankowska, Ismael Pellejero, Ignacio Julian, Hoon Suk Rho, Pedro Pinczowski, Roald M. Tiggelaar, Han Gardeniers, Reyes Mallada, Maria Pilar Pina. On the Improvement of Alveolar‐Like Microfluidic Devices for Efficient Blood Oxygenation. Advanced Materials Technologies. 2021; 6 (5):2001027.
Chicago/Turabian StyleMagdalena Malankowska; Ismael Pellejero; Ignacio Julian; Hoon Suk Rho; Pedro Pinczowski; Roald M. Tiggelaar; Han Gardeniers; Reyes Mallada; Maria Pilar Pina. 2021. "On the Improvement of Alveolar‐Like Microfluidic Devices for Efficient Blood Oxygenation." Advanced Materials Technologies 6, no. 5: 2001027.
We present a simple, versatile and low-cost approach for the preparation of SERS-active regions within a microfluidic channel 50 cm in length. The approach involves the UV-light-driven formation of polyoxometalate-decorated gold nanostructures, [email protected] (POM: H3PW12O40 (PW) and H3PMo12O40 (PMo)), that self-assemble in situ on the surface of the PDMS microchannels without any extra functionalization procedure. The fabricated LoCs were characterized by SEM, UV-Vis, Raman, XRD and XPS techniques. The SERS activity of the resulting [email protected]–coated lab-on-a-chip (LoC) devices was evaluated in both static and flow conditions using Rhodamine R6G. The SERS response of [email protected]–based LoCs was found superior to [email protected] counterparts and outstanding when compared to reported data on [email protected] nanocomposites. We demonstrate the potentialities of both [email protected]–coated LoCs as analytical platforms for real time detection of the organophosphorous pesticide Paraoxon-methyl at 10-6 M concentration level.
Marta Lafuente; Ismael Pellejero; Alberto Clemente; Miguel A. Urbiztondo; Reyes Mallada; Santiago Reinoso; María P. Pina; Luis M. Gandía. In Situ Synthesis of SERS-Active [email protected] Nanostructures in a Microfluidic Device for Real-Time Detection of Water Pollutants. ACS Applied Materials & Interfaces 2020, 12, 36458 -36467.
AMA StyleMarta Lafuente, Ismael Pellejero, Alberto Clemente, Miguel A. Urbiztondo, Reyes Mallada, Santiago Reinoso, María P. Pina, Luis M. Gandía. In Situ Synthesis of SERS-Active [email protected] Nanostructures in a Microfluidic Device for Real-Time Detection of Water Pollutants. ACS Applied Materials & Interfaces. 2020; 12 (32):36458-36467.
Chicago/Turabian StyleMarta Lafuente; Ismael Pellejero; Alberto Clemente; Miguel A. Urbiztondo; Reyes Mallada; Santiago Reinoso; María P. Pina; Luis M. Gandía. 2020. "In Situ Synthesis of SERS-Active [email protected] Nanostructures in a Microfluidic Device for Real-Time Detection of Water Pollutants." ACS Applied Materials & Interfaces 12, no. 32: 36458-36467.
Cu-based Metal Organic Frameworks (MOF) microdevices are applied in sampling and preconcentration of nerve agents (NAs) diluted in gaseous streams. An in-situ electrochemical assisted synthesis of Cu-BTC thick film is carried out to functionalize a Cu modified glass substrate. This simple, rapid, reproducible and easy to integrate MOF synthesis approach, enables the microfabrication of functional microprenconcentrators with large BET surface area (above 2000 cm2) and active pore volume (above 90 nanoliters) for the efficient adsorption of nerve agent molecules along the microfluidic channel 2.5 cm in length. Equilibrium adsorption capacity of the bulk material has been characterized through thermogravimetric analysis after exposure to controlled atmospheres of a sarin gas surrogate, dimethyl methylphosphonate (DMMP), in both dry and humid conditions (30% RH at 293 K). Breakthrough tests at ppm level (162 mg/m3) reveal equilibrium adsorption capacities up to 691 mg/g. The preconcentration performance of such µ-devices when dealing with highly diluted surrogate atmosphere, i.e. 520 ppbV (2.6 mg/m3) at 298 K, leads to preconcentration coefficients up to 171 for sample volume up to 600 STP cm3. We demonstrate the potentialities of Cu-BTC micropreconcentrators as smart first responder tools for “on field” detection of nerve agents in gas phase at relevant conditions.
Fernando Almazán; Miguel A. Urbiztondo; Pablo Serra-Crespo; Beatriz Seoane; Jorge Gascon; Jesús Santamaría; M. P. Pina. Cu-BTC Functional Microdevices as Smart Tools for Capture and Preconcentration of Nerve Agents. ACS Applied Materials & Interfaces 2020, 12, 1 .
AMA StyleFernando Almazán, Miguel A. Urbiztondo, Pablo Serra-Crespo, Beatriz Seoane, Jorge Gascon, Jesús Santamaría, M. P. Pina. Cu-BTC Functional Microdevices as Smart Tools for Capture and Preconcentration of Nerve Agents. ACS Applied Materials & Interfaces. 2020; 12 (38):1.
Chicago/Turabian StyleFernando Almazán; Miguel A. Urbiztondo; Pablo Serra-Crespo; Beatriz Seoane; Jorge Gascon; Jesús Santamaría; M. P. Pina. 2020. "Cu-BTC Functional Microdevices as Smart Tools for Capture and Preconcentration of Nerve Agents." ACS Applied Materials & Interfaces 12, no. 38: 1.
Porous gold lamellar structure with high SERS performance is created by copper chemical etching of a pure gold and pure copper stacked layers. SERS response is recorded for trace level detection of probe molecule in liquid and gas phase.
Adrien Chauvin; Marta Lafuente; Jean Yves Mevellec; Reyes Mallada; Bernard Humbert; Maria Pilar Pina; Pierre-Yves Tessier; Abdelaziz El Mel. Lamellar nanoporous gold thin films with tunable porosity for ultrasensitive SERS detection in liquid and gas phase. Nanoscale 2020, 12, 12602 -12612.
AMA StyleAdrien Chauvin, Marta Lafuente, Jean Yves Mevellec, Reyes Mallada, Bernard Humbert, Maria Pilar Pina, Pierre-Yves Tessier, Abdelaziz El Mel. Lamellar nanoporous gold thin films with tunable porosity for ultrasensitive SERS detection in liquid and gas phase. Nanoscale. 2020; 12 (23):12602-12612.
Chicago/Turabian StyleAdrien Chauvin; Marta Lafuente; Jean Yves Mevellec; Reyes Mallada; Bernard Humbert; Maria Pilar Pina; Pierre-Yves Tessier; Abdelaziz El Mel. 2020. "Lamellar nanoporous gold thin films with tunable porosity for ultrasensitive SERS detection in liquid and gas phase." Nanoscale 12, no. 23: 12602-12612.
Surface-enhanced Raman spectroscopy (SERS) is gaining importance as an ultrasensitive analytical tool for routine high-throughput analysis of a variety of molecular compounds. One of the main challenges is the development of robust, reproducible and cost-effective SERS substrates. In this work, we study the SERS activity of 3D silver mirror-like micro-pyramid structures extended in the z-direction up to 3.7 μm (G0 type substrate) or 7.7 μm (G1 type substrate), prepared by Si-based microfabrication technologies, for trace detection of organophosphorous pesticides, using paraoxon-methyl as probe molecule. The average relative standard deviation (RSD) for the SERS intensity of the peak displayed at 1338 cm-1 recorded over a centimetre scale area of the substrate is below 13% for pesticide concentrations in the range 10-6 to 10-15 mol L-1. This data underlies the spatial uniformity of the SERS response provided by the microfabrication approach. According to finite-difference time-domain (FDTD) simulations, such remarkable feature is mainly due to the contribution on electromagnetic field enhancement of edge plasmon polaritons (EPPs), propagating along the pyramid edges where the pesticide molecules are preferentially adsorbed. Graphical
Marta Lafuente; Erwin J. W. Berenschot; Roald M. Tiggelaar; Sergio G. Rodrigo; Reyes Mallada; Niels R. Tas; María P. Pina. Attomolar SERS detection of organophosphorous pesticides using silver mirror-like micro-pyramids as active substrate. Microchimica Acta 2020, 187, 247 -10.
AMA StyleMarta Lafuente, Erwin J. W. Berenschot, Roald M. Tiggelaar, Sergio G. Rodrigo, Reyes Mallada, Niels R. Tas, María P. Pina. Attomolar SERS detection of organophosphorous pesticides using silver mirror-like micro-pyramids as active substrate. Microchimica Acta. 2020; 187 (4):247-10.
Chicago/Turabian StyleMarta Lafuente; Erwin J. W. Berenschot; Roald M. Tiggelaar; Sergio G. Rodrigo; Reyes Mallada; Niels R. Tas; María P. Pina. 2020. "Attomolar SERS detection of organophosphorous pesticides using silver mirror-like micro-pyramids as active substrate." Microchimica Acta 187, no. 4: 247-10.
In this work, the influence of surface topography on protein crystallization over Nafion® is investigated. Two types of Nafion® based membranes were modified by soft lithographic techniques in order to create different topographies at the micro and nano scale and subsequently tested. From the analysis of the induction time, nucleation and crystal growth rate of Trypsin from Bovine Pancreas, all the patterned Nafion® based membranes show an enhanced nucleation and crystal growth. To provide additional insight to the experimental observations, the wettability properties of the prepared samples and the ratio of the Gibbs free energy of heterogeneous nucleation to homogeneous nucleation were evaluated. The crystallization outcome results from the combined effect of both, the structural and chemical properties of the nucleant Nafion® surface.
M. Polino; C. A. M. Portugal; H. Le The; Roald M. Tiggelaar; J. Eijkel; J. G. Crespo; I. M. Coelhoso; M. P. Pina; R. Mallada. Enhanced Protein Crystallization on Nafion Membranes Modified by Low-Cost Surface Patterning Techniques. Crystal Growth & Design 2020, 20, 2174 -2186.
AMA StyleM. Polino, C. A. M. Portugal, H. Le The, Roald M. Tiggelaar, J. Eijkel, J. G. Crespo, I. M. Coelhoso, M. P. Pina, R. Mallada. Enhanced Protein Crystallization on Nafion Membranes Modified by Low-Cost Surface Patterning Techniques. Crystal Growth & Design. 2020; 20 (4):2174-2186.
Chicago/Turabian StyleM. Polino; C. A. M. Portugal; H. Le The; Roald M. Tiggelaar; J. Eijkel; J. G. Crespo; I. M. Coelhoso; M. P. Pina; R. Mallada. 2020. "Enhanced Protein Crystallization on Nafion Membranes Modified by Low-Cost Surface Patterning Techniques." Crystal Growth & Design 20, no. 4: 2174-2186.
The aim of the study is to develop a compact, robust and maintenance free gas concentration and humidity monitoring system for industrial use in the field of inert process gases. Our multiparameter gas-monitoring system prototype allows the simultaneous measurement of the fluid physical properties (density, viscosity) and water vapor content (at ppm level) under varying process conditions. This approach is enabled by the combination of functionalized and non-functionalized resonating microcantilevers in a single sensing platform. Density and viscosity measuring performance is evaluated over a wide range of gases, temperatures and pressures with non-functionalized microcantilevers. For the humidity measurement, microporous Y-type zeolite and mesoporous silica MCM48 are evaluated as sensing materials. An easily scalable functionalization method to high-throughput production is herein adopted. Experimental results with functionalized microcantilevers exposed to water vapor (at ppm level) indicate that frequency changes cannot be attributed to a mass effect alone, but also stiffness effects dependent on adsorption of water and working temperature must be considered. To support this hypothesis, the mechanical response of such microcantilevers has been modelled considering both effects and the simulated results validated by comparison against experimental data.
Christof Huber; Maria Pilar Pina; Juan José Morales; Alexandre Mehdaoui. A Multiparameter Gas-Monitoring System Combining Functionalized and Non-Functionalized Microcantilevers. Micromachines 2020, 11, 283 .
AMA StyleChristof Huber, Maria Pilar Pina, Juan José Morales, Alexandre Mehdaoui. A Multiparameter Gas-Monitoring System Combining Functionalized and Non-Functionalized Microcantilevers. Micromachines. 2020; 11 (3):283.
Chicago/Turabian StyleChristof Huber; Maria Pilar Pina; Juan José Morales; Alexandre Mehdaoui. 2020. "A Multiparameter Gas-Monitoring System Combining Functionalized and Non-Functionalized Microcantilevers." Micromachines 11, no. 3: 283.
Lung disease is one of the most important causes of high morbidity in preterm infants. In this work, we study a simple and easy to fabricate microfluidic device that demonstrates a great potential for blood oxygenation. A meander type architecture with double side vertical membrane arrangement has been selected as reference model to investigate the oxygenation process. The design criteria for the fabricated devices has been to maximize the oxygen saturation level while ensuring the physiological blood flow in order to avoid thrombus formation and channel blockage during operation. A mathematical model for the oxygen transfer has been developed and validated by the experimental study. The obtained results demonstrate that blood was successfully oxygenated up to approximately 98% of O2 saturation and that the oxygen transfer rate at 1 mL/min blood flow rate was approximately 92 mL/min·m2. Finally, a sensitivity analysis of the key parameters, i.e. size of the channel, oxygen concentration in the gas phase and oxygen permeation properties of the membrane, is carried out to discuss the performance limits and to settle the guidelines for future developments.
Magdalena Malankowska; I. Julian; Ismael Pellejero; H.S. Rho; S. Schlautmann; Roald M. Tiggelaar; M.P. Pina; H.J.G.E. Gardeniers; R. Mallada. Understanding blood oxygenation in a microfluidic meander double side membrane contactor. Sensors and Actuators B: Chemical 2019, 288, 414 -424.
AMA StyleMagdalena Malankowska, I. Julian, Ismael Pellejero, H.S. Rho, S. Schlautmann, Roald M. Tiggelaar, M.P. Pina, H.J.G.E. Gardeniers, R. Mallada. Understanding blood oxygenation in a microfluidic meander double side membrane contactor. Sensors and Actuators B: Chemical. 2019; 288 ():414-424.
Chicago/Turabian StyleMagdalena Malankowska; I. Julian; Ismael Pellejero; H.S. Rho; S. Schlautmann; Roald M. Tiggelaar; M.P. Pina; H.J.G.E. Gardeniers; R. Mallada. 2019. "Understanding blood oxygenation in a microfluidic meander double side membrane contactor." Sensors and Actuators B: Chemical 288, no. : 414-424.
This experimental study explores the potential of supported ionic liquid membranes (SILMs) based on protic imidazolium ionic liquids (ILs) and randomly nanoporous polybenzimidazole (PBI) supports for CH4/N2 separation. In particular, three classes of SILMs have been prepared by the infiltration of porous PBI membranes with different protic moieties: 1-H-3-methylimidazolium bis (trifluoromethane sulfonyl)imide; 1-H-3-vinylimidazolium bis(trifluoromethane sulfonyl)imide followed by in situ ultraviolet (UV) polymerization to poly[1-(3H-imidazolium)ethylene] bis(trifluoromethanesulfonyl)imide. The polymerization process has been monitored by Fourier transform infrared (FTIR) spectroscopy and the concentration of the protic entities in the SILMs has been evaluated by thermogravimetric analysis (TGA). Single gas permeability values of N2 and CH4 at 313 K, 333 K and 363 K were obtained from a series of experiments conducted in a batch gas permeance system. The results obtained were assessed in terms of the preferential cavity formation and favorable solvation of methane in the apolar domains of the protic ionic network. The most attractive behavior exhibited poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide polymeric ionic liquid (PIL) cross-linked with 1% divinylbenzene supported membranes, showing stable performance when increasing the upstream pressure. The CH4/N2 permselectivity value of 2.1 with CH4 permeability of 156 Barrer at 363 K suggests that the transport mechanism of the as-prepared SILMs is solubility-dominated.
Parashuram Kallem; Christophe Charmette; Martin Drobek; Anne Julbe; Reyes Mallada; Maria Pilar Pina. Exploring the Gas-Permeation Properties of Proton-Conducting Membranes Based on Protic Imidazolium Ionic Liquids: Application in Natural Gas Processing. Membranes 2018, 8, 75 .
AMA StyleParashuram Kallem, Christophe Charmette, Martin Drobek, Anne Julbe, Reyes Mallada, Maria Pilar Pina. Exploring the Gas-Permeation Properties of Proton-Conducting Membranes Based on Protic Imidazolium Ionic Liquids: Application in Natural Gas Processing. Membranes. 2018; 8 (3):75.
Chicago/Turabian StyleParashuram Kallem; Christophe Charmette; Martin Drobek; Anne Julbe; Reyes Mallada; Maria Pilar Pina. 2018. "Exploring the Gas-Permeation Properties of Proton-Conducting Membranes Based on Protic Imidazolium Ionic Liquids: Application in Natural Gas Processing." Membranes 8, no. 3: 75.
A surface-enhanced Raman scattering (SERS)-based sensor was developed for the label-free real-time gas phase detection of dimethyl methylphosphonate (DMMP); a surrogate molecule of the G-series nerve agents which are of particular concern due to its extreme toxicity, persistence and previous deployment. The SERS platform was designed using simple elements (Au nano-particles) coated with a citrate layer, and a self-assembly procedure that yields near- optimum distances among the nanoparticles. The citrate coating acts as an effective trap of the target molecules on the immediate vicinity of the Au nanoparticle surface under ambient conditions by reversible hydrogen bonding type interactions. For the first time, we have been able to detect sub-ppm concentrations of DMMP in gas phase (130 parts-per-billion), as might be found on potential emergency scenarios. The high sensitivity, simple preparation and reusability of the SERS platforms developed in this work open up the way for immediate detection of chemical warfare agents in realistic scenarios.
Marta Lafuente; Ismael Pellejero; Víctor Sebastián; Miguel A. Urbiztondo; Reyes Mallada; M. Pilar Pina; Jesús Santamaría. Highly sensitive SERS quantification of organophosphorous chemical warfare agents: A major step towards the real time sensing in the gas phase. Sensors and Actuators B: Chemical 2018, 267, 457 -466.
AMA StyleMarta Lafuente, Ismael Pellejero, Víctor Sebastián, Miguel A. Urbiztondo, Reyes Mallada, M. Pilar Pina, Jesús Santamaría. Highly sensitive SERS quantification of organophosphorous chemical warfare agents: A major step towards the real time sensing in the gas phase. Sensors and Actuators B: Chemical. 2018; 267 ():457-466.
Chicago/Turabian StyleMarta Lafuente; Ismael Pellejero; Víctor Sebastián; Miguel A. Urbiztondo; Reyes Mallada; M. Pilar Pina; Jesús Santamaría. 2018. "Highly sensitive SERS quantification of organophosphorous chemical warfare agents: A major step towards the real time sensing in the gas phase." Sensors and Actuators B: Chemical 267, no. : 457-466.
One of the main limitations of the technique surface-enhanced Raman scattering (SERS) for chemical detection relies on the homogeneity, reproducibility and reusability of the substrates. In this work, SERS active platforms based on 3D-fractal microstructures is developed by combining corner lithography and anisotropic wet etching of silicon, to extend the SERS-active area into 3D, with electrostatically driven [email protected] nanoparticles (NPs) assembly, to ensure homogeneous coating of SERS active NPs over the entire microstructured platforms. Strong SERS intensities are achieved using 3D-fractal structures compared to 2D-planar structures; leading to SERS enhancement factors for R6G superior than those merely predicted by the enlarged area effect. The SERS performance of Au monolayer-over-mirror configuration is demonstrated for the label-free real-time gas phase detection of 1.2 ppmV of dimethyl methylphosphonate (DMMP), a common surrogate of G-nerve agents. Thanks to the hot spot accumulation on the corners and tips of the 3D-fractal microstructures, the main vibrational modes of DMMP are clearly identified underlying the spectral selectivity of the SERS technique. The Raman acquisition conditions for SERS detection in gas phase have to be carefully chosen to avoid photo-thermal effects on the irradiated area.
Marta Lafuente; Erwin J. W. Berenschot; Roald M. Tiggelaar; Reyes Mallada; Niels R. Tas; Maria P. Pina. 3D Fractals as SERS Active Platforms: Preparation and Evaluation for Gas Phase Detection of G-Nerve Agents. Micromachines 2018, 9, 60 .
AMA StyleMarta Lafuente, Erwin J. W. Berenschot, Roald M. Tiggelaar, Reyes Mallada, Niels R. Tas, Maria P. Pina. 3D Fractals as SERS Active Platforms: Preparation and Evaluation for Gas Phase Detection of G-Nerve Agents. Micromachines. 2018; 9 (2):60.
Chicago/Turabian StyleMarta Lafuente; Erwin J. W. Berenschot; Roald M. Tiggelaar; Reyes Mallada; Niels R. Tas; Maria P. Pina. 2018. "3D Fractals as SERS Active Platforms: Preparation and Evaluation for Gas Phase Detection of G-Nerve Agents." Micromachines 9, no. 2: 60.
The novel concept of a microfluidic chip with an integrated three-dimensional fractal geometry with nanopores, acting as a gas transport membrane, is presented. The method of engineering the 3D fractal structure is based on a combination of anisotropic etching of silicon and corner lithography. The permeation of oxygen and carbon dioxide through the fractal membrane is measured and validated theoretically. The results show high permeation flux due to low resistance to mass transfer because of the hierarchical branched structure of the fractals, and the high number of the apertures. This approach offers an advantage of high surface to volume ratio and pores in the range of nanometers. The obtained results show that the gas permeation through the nanonozzles in the form of fractal geometry is remarkably enhanced in comparison to the commonly-used polydimethylsiloxane (PDMS) dense membrane. The developed chip is envisioned as an interesting alternative for gas-liquid contactors that require harsh conditions, such as microreactors or microdevices, for energy applications.
Magdalena Malankowska; Stefan Schlautmann; Erwin J. W. Berenschot; Roald M. Tiggelaar; Maria Pilar Pina; Reyes Mallada; Niels R. Tas; Han Gardeniers. Three-Dimensional Fractal Geometry for Gas Permeation in Microchannels. Micromachines 2018, 9, 45 .
AMA StyleMagdalena Malankowska, Stefan Schlautmann, Erwin J. W. Berenschot, Roald M. Tiggelaar, Maria Pilar Pina, Reyes Mallada, Niels R. Tas, Han Gardeniers. Three-Dimensional Fractal Geometry for Gas Permeation in Microchannels. Micromachines. 2018; 9 (2):45.
Chicago/Turabian StyleMagdalena Malankowska; Stefan Schlautmann; Erwin J. W. Berenschot; Roald M. Tiggelaar; Maria Pilar Pina; Reyes Mallada; Niels R. Tas; Han Gardeniers. 2018. "Three-Dimensional Fractal Geometry for Gas Permeation in Microchannels." Micromachines 9, no. 2: 45.
Liquid-induced phase-separation micromolding (LIPSμM) has been successfully used for manufacturing hierarchical porous polybenzimidazole (HPBI) microsieves (42–46% porosity, 30–40 μm thick) with a specific pore architecture (pattern of macropores: ∼9 μm in size, perforated, dispersed in a porous matrix with a 50–100 nm pore size). Using these microsieves, proton-exchange membranes were fabricated by the infiltration of a 1H-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide liquid and divinylbenzene (as a cross-linker), followed by in situ UV polymerization. Our approach relies on the separation of the ion conducting function from the structural support function. Thus, the polymeric ionic liquid (PIL) moiety plays the role of a proton conductor, whereas the HPBI microsieve ensures the mechanical resistance of the system. The influence of the porous support architecture on both proton transport performance and mechanical strength has been specifically investigated by means of comparison with straight macroporous (36% porosity) and randomly nanoporous (68% porosity) PBI counterparts. The most attractive results were obtained with the poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide PIL cross-linked with 1% divinylbenzene supported on HPBI membranes with a 21-μm-thick skin layer, achieving conductivity values up to 85 mS cm–1 at 200 °C under anhydrous conditions and in the absence of mineral acids.
Parashuram Kallem; Martin Drobek; Anne Julbe; Erik J. Vriezekolk; Reyes Mallada; Maria Pilar Pina. Hierarchical Porous Polybenzimidazole Microsieves: An Efficient Architecture for Anhydrous Proton Transport via Polyionic Liquids. ACS Applied Materials & Interfaces 2017, 9, 14844 -14857.
AMA StyleParashuram Kallem, Martin Drobek, Anne Julbe, Erik J. Vriezekolk, Reyes Mallada, Maria Pilar Pina. Hierarchical Porous Polybenzimidazole Microsieves: An Efficient Architecture for Anhydrous Proton Transport via Polyionic Liquids. ACS Applied Materials & Interfaces. 2017; 9 (17):14844-14857.
Chicago/Turabian StyleParashuram Kallem; Martin Drobek; Anne Julbe; Erik J. Vriezekolk; Reyes Mallada; Maria Pilar Pina. 2017. "Hierarchical Porous Polybenzimidazole Microsieves: An Efficient Architecture for Anhydrous Proton Transport via Polyionic Liquids." ACS Applied Materials & Interfaces 9, no. 17: 14844-14857.
Poly-ionic liquids (PILs) have triggered great interest as all solid state flexible electrolytes because of safety and superior thermal, chemical and electrochemical stability. It is of great importance to fabricate highly conductive electrolyte membranes capable to operate above 120°C under anhydrous conditions and in absence of mineral acids, without sacrificing the mechanical behavior. Herein, the diminished dimensional and mechanical stability of poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide has been improved thanks to its infiltration on a polybenzimidale (PBI) support with specific pore architecture. Our innovative solution is based on the synergic combination of an emerging class of materials and sustainable large scale manufacturing techniques (UV polymerization and replication by microtransfer-moulding). Following this approach, the PIL plays the proton conduction role and the PBI microsieve (SPBI) mainly provides the mechanical reinforcement. Among the resulting electrolyte membranes, conductivity values above 50 mS∙cm-1 at 200 °C and 10.7 MPa as tensile stress are shown by straight microchannels of poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide crosslinked with 1% of dyvinylbenzene embedded in a PBI microsieve with well-defined porosity (36%) and pore diameter (17 µm).
Parashuram Kallem; Adela Eguizabal; Reyes Mallada; Maria Pilar Pina. Constructing Straight Polyionic Liquid Microchannels for Fast Anhydrous Proton Transport. ACS Applied Materials & Interfaces 2016, 8, 35377 -35389.
AMA StyleParashuram Kallem, Adela Eguizabal, Reyes Mallada, Maria Pilar Pina. Constructing Straight Polyionic Liquid Microchannels for Fast Anhydrous Proton Transport. ACS Applied Materials & Interfaces. 2016; 8 (51):35377-35389.
Chicago/Turabian StyleParashuram Kallem; Adela Eguizabal; Reyes Mallada; Maria Pilar Pina. 2016. "Constructing Straight Polyionic Liquid Microchannels for Fast Anhydrous Proton Transport." ACS Applied Materials & Interfaces 8, no. 51: 35377-35389.
Flexible polybenzimidazole (PBI) micromonoliths prepared by microtransfer moulding are herein proposed for the first time as G-S contactors for catalytic applications. Macroporous polymeric supports with 20 μm as characteristic length and 70,000 m−1 as S/V ratio have been coated by covalent linkage with Pt supported on amino functionalized ETS-10 crystals. As a proof of concept, the catalytic performance of the Pt modified PBI micromonoliths has been successfully demonstrated for indoor quality control, i.e. n-hexane removal at ppm level.
A. Eguizábal; M.A. Urbiztondo; M.P. Pina. Pt based catalytic coatings on poly(benzimidazole) micromonoliths for indoor quality control. Catalysis Today 2014, 241, 114 -124.
AMA StyleA. Eguizábal, M.A. Urbiztondo, M.P. Pina. Pt based catalytic coatings on poly(benzimidazole) micromonoliths for indoor quality control. Catalysis Today. 2014; 241 ():114-124.
Chicago/Turabian StyleA. Eguizábal; M.A. Urbiztondo; M.P. Pina. 2014. "Pt based catalytic coatings on poly(benzimidazole) micromonoliths for indoor quality control." Catalysis Today 241, no. : 114-124.
A novel 4-step microfabrication process is proposed in this work to prepare arrays of c-oriented silicalite (SIL-1) micromembranes on customized silicon nitride (Si3Nx) microsieves. The arrays are integrated on chip and their overall porosity values can be tuned from 1.6% to 19.9%. A low stress Si3Nx microfabricated sieve has been used as support to reinforce via mechanical interlocking and to reduce the effects of the residual stress during membrane processing. The secondary hydrothermal growth over the Si3Nx microsieves also changes the SIL-1 chemistry, improving its affinity towards CO2 adsorption. As a result, the SIL-1/Si3Nx micromembranes integrated on chip facilitate the preferential permeation of CO2 in CO2/H2 mixtures, showing a maximum CO2/H2 separation factor of 16.9 and a CO2 permeance of 8.2×10−7 mol m−2 s−1 Pa−1 at ambient conditions.
Ismael Pellejero; M.A. Urbiztondo; M.P. Pina; J. Santamaria. Reinforced SIL-1 micromembranes integrated on chip: Application to CO2 separation. Journal of Membrane Science 2014, 460, 34 -45.
AMA StyleIsmael Pellejero, M.A. Urbiztondo, M.P. Pina, J. Santamaria. Reinforced SIL-1 micromembranes integrated on chip: Application to CO2 separation. Journal of Membrane Science. 2014; 460 ():34-45.
Chicago/Turabian StyleIsmael Pellejero; M.A. Urbiztondo; M.P. Pina; J. Santamaria. 2014. "Reinforced SIL-1 micromembranes integrated on chip: Application to CO2 separation." Journal of Membrane Science 460, no. : 34-45.
Microfabricated Si cantilevers with different sensitive layers have been used for the detection of volatile hydrocarbons (ethanol and toluene) in air at ppm concentration levels. A variety of coatings has been explored, including several polymers (PEUT, PECH, PIB) and zeolites both organophilic (silicalite) and hydrophilic (zeolite Y, zeolite A). Also, different sensor dimensions have been studied, in an attempt to understand the trade off between a larger sensor surface (and therefore a larger sensitive area) and better mechanical properties. The main sensor performance parameters have been calculated and compared for the different coatings and sensor designs. Also, some scarcely studied aspects such as the evolution of the Q factor with zeolite loading have been studied. Among the tested, detection limits below 24 ppmV for ethanol and 26 ppmV for toluene are obtained with zeolite type coatings; while the corresponding values for the polymer-coated are over 260 and 43 ppmV, respectively. The performance of zeolite-coated cantilevers could be further increased by degassing at a sufficiently high temperature to remove the adsorbed species, thus releasing their nanoporous structure for the next sensing cycle. To this end, cantilevers with integrated heaters have been developed which enabled lowering the limits of detection down to the single ppm level.
M.A. Urbiztondo; A. Peralta; I. Pellejero; J. Sesé; M.P. Pina; I. Dufour; J. Santamaría. Detection of organic vapours with Si cantilevers coated with inorganic (zeolites) or organic (polymer) layers. Sensors and Actuators B: Chemical 2012, 171-172, 822 -831.
AMA StyleM.A. Urbiztondo, A. Peralta, I. Pellejero, J. Sesé, M.P. Pina, I. Dufour, J. Santamaría. Detection of organic vapours with Si cantilevers coated with inorganic (zeolites) or organic (polymer) layers. Sensors and Actuators B: Chemical. 2012; 171-172 ():822-831.
Chicago/Turabian StyleM.A. Urbiztondo; A. Peralta; I. Pellejero; J. Sesé; M.P. Pina; I. Dufour; J. Santamaría. 2012. "Detection of organic vapours with Si cantilevers coated with inorganic (zeolites) or organic (polymer) layers." Sensors and Actuators B: Chemical 171-172, no. : 822-831.
Nanoporous microcantilevers entirely constituted by silicalite type zeolite have been fabricated by integrating the seeded growth hydrothermal zeolite synthesis step in a conventional microfabrication scheme using Si technologies. The mechanical properties of the as prepared polycrystalline beams, ranging from 200 μm to 2000 μm in length and 20 to 120 μm in width have been fully characterized. In particular, Young modulus and quality factor of silicalite-only cantilevers before and after detemplation process have been determined by using mechanical resonance excitation and optical read-out. As a “proof of concept”, the nanoporous zeolitic cantilevers have been applied to ethanol detection at ppm level. The sensing performance of the as prepared silicalite-only cantilevers has been compared with the exhibited by conventional cantilevers consisting on microfabricated Si beams coated with individual silicalite crystals.
Ismael Pellejero; J. Agustí; Miguel Urbiztondo; Javier Sesé; M.P. Pina; J. Santamaría; Gabriel Abadal. Nanoporous silicalite-only cantilevers as micromechanical sensors: Fabrication, resonance response and VOCs sensing performance. Sensors and Actuators B: Chemical 2012, 168, 74 -82.
AMA StyleIsmael Pellejero, J. Agustí, Miguel Urbiztondo, Javier Sesé, M.P. Pina, J. Santamaría, Gabriel Abadal. Nanoporous silicalite-only cantilevers as micromechanical sensors: Fabrication, resonance response and VOCs sensing performance. Sensors and Actuators B: Chemical. 2012; 168 ():74-82.
Chicago/Turabian StyleIsmael Pellejero; J. Agustí; Miguel Urbiztondo; Javier Sesé; M.P. Pina; J. Santamaría; Gabriel Abadal. 2012. "Nanoporous silicalite-only cantilevers as micromechanical sensors: Fabrication, resonance response and VOCs sensing performance." Sensors and Actuators B: Chemical 168, no. : 74-82.