Exploring the Implementation of GaAsBi Alloys as Strain-Reducing Layers in InAs/GaAs Quantum Dots.

This paper investigates the effect of GaAsBi strain reduction layers (SRLs) on InAs QDs with different Bi fluxes to achieve nanostructures with improved temperature stability. The SRLs are grown at a lower temperature (370 °C) than the usual capping temperature for InAs QDs (510 °C). The study finds that GaAs capping at low temperatures reduces QD decomposition and leads to larger pyramidal dots but also increases the threading dislocation (TD) density.

Microplastics in the stomach content of the commercial fish species Scomber colias in the Gulf of Cadiz, SW Europe.

Concerning microplastics (MPs) contamination is increasing due their negative impacts on marine food webs and their potential toxicity to wildlife and humans. In this study, we analyze the presence of MPs in the stomachs of the commercial fish species Scomber colias (Atlantic chub mackerel) in the Gulf of Cadiz (GoC). Out of the 104 analyzed stomachs, 90.

Simple and cost-effective pH and T sensors from top to bottom: New chemical probes based on sonogel-carbon transducers for plasma analyses.

The present work introduces two novel approaches to fabricate simple and cost-effective pH and temperature probes. Sinusoidal voltage methodologies were employed to electrodeposit polyaniline (PANI) at different growth times (10-20 min) on the surface of an affordable Sonogel-Carbon electrode to conform a robust pH sensor. The presence of PANI and its phases were corroborated by electrochemical means.

Development of a molecularly imprinted membrane for selective, high-sensitive, and on-site detection of antibiotics in waters and drugs: Application for sulfamethoxazole.

Sulfonamides are among the widespread bacterial antibiotics. Despite this, their quick emergence constitutes a serious problem for ecosystems and human health. Therefore, there is an increased interest in developing relevant detection method for antibiotics in different matrices.

Sustainable Recovery of Platinum Group Metals from Spent Automotive Three-Way Catalysts through a Biogenic Thiosulfate-Copper-Ammonia System.

This study explores an eco-friendly method for recovering platinum group metals from a synthetic automotive three-way catalyst (TWC). Bioleaching of palladium (Pd) using the thiosulfate-copper-ammonia leaching processes, with biogenic thiosulfate sourced from a bioreactor used for biogas biodesulfurization, is proposed as a sustainable alternative to conventional methods. Biogenic thiosulfate production was optimized in a gas-lift bioreactor by studying the pH (8-10) and operation modes (batch and continuous) under anoxic and microaerobic conditions for 35 d.

Bioleaching of the α-alumina layer of spent three-way catalysts as a pretreatment for the recovery of platinum group metals.

Acid bioleaching of Al by Acidithiobacillus thiooxidans has been explored as an environmentally friendly pretreatment to facilitate the extraction of platinum group metals from spent three-way catalysts (TWC). Biogenic sulfur obtained from desulfurization bioreactors improved the production of acid by A. thiooxidans compared to commercially available elemental sulfur.

Magnetic Molecularly Imprinted Chitosan Combined with a Paper-Based Analytical Device for the Smartphone Discrimination of Tryptophan Enantiomers.

The separation of enantiomers plays a critical role in pharmaceutical development, ensuring therapeutic efficacy, safety, and patent protection. It enables the production of enantiopure drugs and enhances our understanding of the properties of chiral compounds. In this study, a straightforward and effective chiral detection strategy was developed for distinguishing between tryptophan (TRP) enantiomers.

Feather-like Gold Nanostructures Anchored onto 3D Mesoporous Laser-Scribed Graphene: A Highly Sensitive Platform for Enzymeless Glucose Electrochemical Detection in Neutral Media.

The authors present a novel sensing platform for a disposable electrochemical, non-enzymatic glucose sensor strip at physiological pH. The sensing material is based on dendritic gold nanostructures (AuNs) resembling feather branches, which are electrodeposited onto a laser-scribed 3D graphene electrode (LSGE). The LSGEs were fabricated via a one-step laser scribing process on a commercially available polyimide sheet.

Geographical Classification of Saffron ( L.) Using Total and Synchronous Fluorescence Combined with Chemometric Approaches.

There is an increasing interest in food science for high-quality natural products with a distinct geographical origin, such as saffron. In this work, the excitation-emission matrix (EEM) and synchronous fluorescence were used for the first time to geographically discriminate between Moroccan saffron from Taroudant, Ouarzazate, and Azilal. Moreover, to differentiate between Afghan, Iranian, and Moroccan saffron, a unique fingerprint was assigned to each sample by visualizing the EEM physiognomy.

Incorporation of carbon black into a sonogel matrix: improving antifouling properties of a conducting polymer ceramic nanocomposite.

A new electrochemical sensor device has been developed through the modification of a polyaniline-silicon oxide network with carbon black (CB). Enhanced electrical conductivity and antifouling properties have been achieved due to the integration of this cheap nanomaterial into the bulk of the sensor. The structure of the developed material was characterized using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy techniques.

Contamination from microplastics and other anthropogenic particles in the digestive tracts of the commercial species Engraulis encrasicolus and Sardina pilchardus.

Fragments of microplastics (<5 mm) found in commercial species of fish, crustaceans, and bivalves, are an issue of global concern. The bioaccumulation of microplastics and other anthropogenic particles in different levels of the food web may provoke unwanted impacts on marine ecosystems and cause pernicious effects on human health. Here, we study the presence of anthropogenic particles and the fraction of microplastics in the target organs of two representative commercial fish species in Spain; the European anchovy (Engraulis encrasicolus) and the European pilchard (Sardina pilchardus).

Fast Analysis of Caffeic Acid-Related Molecules in Instant Coffee by Reusable Sonogel-Carbon Electrodes.

Reusable Sonogel-Carbon electrodes containing carbon black (SNGC-CB) have been used for the electrochemical analysis of caffeic acid (CA) in real matrices. Measurements were firstly performed in standard solutions, in which SNGC-CB electrodes allowed the electrochemical determination of CA with high sensitivity and low limit of detection, equal to 0.76 μM.

What Is Left for Real-Life Lactate Monitoring? Current Advances in Electrochemical Lactate (Bio)Sensors for Agrifood and Biomedical Applications.

Monitoring of lactate is spreading from the evident clinical environment, where its role as a biomarker is notorious, to the agrifood ambit as well. In the former, lactate concentration can serve as a useful indicator of several diseases (e.g.

Robocasting and Laser Micromachining of Sol-Gel Derived 3D Silica/Gelatin/β-TCP Scaffolds for Bone Tissue Regeneration.

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable viscosity prepared by mixing tetraethoxysilane (TEOS), gelatin and β-tricalcium phosphate (β-TCP) allowed for the manufacture of 3D scaffolds consisting of a 3D square mesh of interpenetrating rods, with macropore size of 354.0 ± 17.

A New Electrochemical Method to Determine Tryptophan in Fruit Juices: Development and Validation.

Tryptophan (Trp) is an essential amino acid usually found in fruit juices. Its determination is necessary for food companies because of its relation to human health. In this work, a new electrochemical method based on sonogel-carbon electrodes (SNGCEs) was developed and validated using an ultra performance liquid chromatography (UPLC) method as a reference method for the determination of Trp in fruit juices.

An electrochemical alternative for evaluating the antioxidant capacity in walnut kernel extracts.

A fast, precise and inexpensive alternative for evaluating the antioxidant activity (AA) in walnut kernel extracts is proposed. Traditional ABTS assay and an electrochemical index approach have been applied to evaluate the AA in walnuts. A fast and efficient defatting of the walnuts by ultrasound assisted extraction (UAE) was carried out.

Spectroscopic Ellipsometry Study on Tuning the Electrical and Optical Properties of Zr-Doped ZnO Thin Films Grown by Atomic Layer Deposition.

This work reports the ellipsometry analysis of atomic layer deposition (ALD) films of ZnO doped with Zr to determine parameters like free carrier concentration and mobility. Thin films of zinc oxide (ZnO) and Zr-doped ZnO of thickness ∼100 nm were prepared by atomic layer deposition on sapphire, SiO/Si(100), and Si(100) substrates. Variable-angle spectroscopic ellipsometry was used to study their optical properties in the 0.

A novel magnetic molecularly imprinted polymer for selective extraction and determination of quercetin in plant samples.

Molecularly imprinted polymers that mimic the binding mechanism of antibodies and their antigens exhibit several advantages, such as fast synthesis, low cost, high stability, and allow to overcome the ethical issues associated with antibody farming in animals. Herein, a novel strategy combining the magnetic molecularly imprinted polymer (MMIP) as an artificial antibody with a fluorescence procedure for the detection of quercetin in plant samples was designed. The MMIP was synthesized via a radical polymerization process to recognize specific functional groups of quercetin using a green technique based on high energy ultrasound irradiation.

A Sensitive Electrochemical Sensor Based on Sonogel-Carbon Material Enriched with Gold Nanoparticles for Melatonin Determination.

In this work, the development of an electrochemical sensor for melatonin determination is presented. The sensor was based on Sonogel-Carbon electrode material (SNGCE) and Au nanoparticles (AuNPs). The low-cost and environmentally friendly SNGCE material was prepared by the ultrasound-assisted sonogel method.

Polyaniline Nanofibers-Embedded Gold Nanoparticles Obtained by Template-Free Procedure with Immobilization Prospects.

In this work, template-free nanostructured conducting polymers (nCPs)-embedded gold nanoparticles (AuNPs) from aniline, thiophene and 3,4-ethylenedioxythiophene have been prepared via a one-pot sonochemical method. The synthesis of the nanocomposite (nCPs-AuNPs) was achieved in a short period of time (5-10 min), by applying high-energy ultrasound to an aqueous mixture of a CP precursor monomer and KAuCl, in the presence of LiClO as dopant. The synthesis process is simpler, greener and faster in comparison to other procedures reported in the literature.

E-Tongues/Noses Based on Conducting Polymers and Composite Materials: Expanding the Possibilities in Complex Analytical Sensing.

Conducting polymers (CPs) are extensively studied due to their high versatility and electrical properties, as well as their high environmental stability. Based on the above, their applications as electronic devices are promoted and constitute an interesting matter of research. This review summarizes their application in common electronic devices and their implementation in electronic tongues and noses systems (E-tongues and E-noses, respectively).

Simultaneous Detection of Glucose and Fructose in Synthetic Musts by Multivariate Analysis of Silica-Based Amperometric Sensor Signals.

Silica-based electrodes which permanently include a graphite/Au nanoparticles composite were tested for non-enzymatic detection of glucose and fructose. The composite material showed an effective electrocatalytic activity, to achieve the oxidation of the two analytes at quite low potential values and with good linearity. Reduced surface passivation was observed even in presence of organic species normally constituting real samples.

Fast microwave-assisted synthesis of magnetic molecularly imprinted polymer for sulfamethoxazole.

A fast and simple strategy based on the microwave technique for the preparation of magnetic molecularly imprinted polymers (MMIPs) is proposed for the selective determination of sulfamethoxazole (SMX). The MMIPs were synthesized at 70 °C in 20 min, being much faster than the conventional techniques. A computational approach based on density functional theory was used to design the MMIP and compare the two most used monomers in MIPs, including methacrylic acid (MAA) and acrylamide (AM).