Electrochemical molecularly imprinted polymer sensor for simple and fast analysis of tetrodotoxin in seafood.

Tetrodotoxin (TTX) is a marine biotoxin whose biosynthesis is associated with the pufferfish. Its distribution is primarily focused in Asian and tropical marine areas. Currently, this group of toxins is classified as emerging in Europe, and its presence could be related to climate change. This incidence has prompted the European Union, with the European Food Safety Authority, to establish control and monitoring mechanisms for TTX in marine products in Europe. In this context, the development of analytical tools capable of ensuring the safety of food products, especially seafood and fish, is a crucial task. This study describes the development of a molecularly imprinted polymer (MIP) based electrochemical sensor for the analysis of TTX. The MIP was synthesized through the electropolymerization of a functional monomer, ortho-phenylenediamine in the presence of a dummy template, voglibose. The MIP sensor was constructed on a screen-printed gold electrode and characterized by cyclic voltammetry. Differential pulse voltammetry, using a redox probe ([Fe(CN)6]3-/4-), was used in the analysis protocol. The developed sensor exhibited a linear response between 5.0 µg mL-1 and 25.0 µg mL-1, with a limit of detection of 1.14 µg mL-1. Its high imprinting efficiency conferred outstanding selectivity towards TTX. The sensor's applicability was confirmed through recovery assays on spiked mussel samples, achieving recoveries of 81.0 %, 110.2 %, and 102.5 % for external standard addition at 30.0, 44.0, and 60.0 µg kg-1, respectively, with relative standard deviations below 15 %. These results are comparable to those obtained using Hydrophilic Interaction Liquid Chromatography coupled with Tandem Mass Spectrometry, a validated method carried out by the European Reference Laboratory for Marine Biotoxins. Thus, the MIP sensor represents a portable, simple, and fast tool with essential analytical functionalities for the sampling phase and pre-selection of laboratory samples for analysis.

Comparative life cycle assessment of non-thermal plasma for the removal of pharmaceuticals from wastewater.

Wastewater effluents are a continuous source of pharmaceuticals in water bodies, which pose a serious environmental threat to aquatic ecosystems. This work provides a comprehensive technical, environmental and cost assessments of different advanced quaternary treatments for wastewater effluents, with special focus on novel Non-Thermal Plasma technology. For this porpouse Non-Thermal Plasma, Sand Filtration + Ozonation, Ultrafiltration, Ultrafiltration + Nanofiltration and Ultrafiltration + Reverse Osmosis technologies were compared with UV disinfection-based technology. This work applies the Life Cycle Analysis tool for the impact environmental assessment using both ReciPE 2016(H) method and, for a more detailed analysis of the contribution of pharmaceuticals to freshwater ecotoxicity category of impact, the USETOX method, which was integrated with 7 new characterisation factors. The results obtained showed overall removal efficiency of pharmaceuticals always higher than 80%, with performances in descending order of Ultrafiltration + Reverse Osmosis > Sand Filtration + Ozonation > Ultrafiltration + Nanofiltration > Non-Thermal Plasma, being Sand Filtration + Ultraviolet disinfection and standalone Ultrafiltration comparatively not suitable for pharmaceuticals removal. Regarding the target pharmaceuticals proposed on the EU Directive 271/91 revision, the Non-Thermal Plasma perform better towards venlafaxine than Sand Filtration + Ozonation, and towards diclofenac and carbamazepine than Ultrafiltration + Nanofiltration. Ultrafiltration + Nanofiltration and Non-Thermal Plasma showed better environmental performance than Sand Filtration + Ozonation and Ultrafiltration + Reverse Osmosis in 7 out of 18 categories of impact (ReciPe method), with Ultrafiltration + Nanofiltration being more advantageous than Non-Thermal Plasma in human and ecotoxicity-related categories of impact, and Non-Thermal Plasma more advantageous in Global Warming, Fossil Resource Scarcity, and Fine Particulate Matter Formation. Regrading Freshwater Ecotoxicity (USEtox method), the quaternary treatment configuration and its energy demand affect the Freshwater final value of impact more than the presence of pharmaceuticals. Under the conditions tested, the Non-Thermal Plasma provided the lower OPEX (0.24 € m-3) than other tested technologies, showing an interesting compromise between pharmaceuticals removal efficiency, environmental impacts, and economic operational cost.

Next-generation sequencing improves precision medicine in hearing loss.

Background: An early etiological diagnosis of hearing loss positively impacts children's quality of life including language and cognitive development. Even though hearing loss associates with extremely high genetic and allelic heterogeneity, several studies have proven that Next-Generation Sequencing (NGS)-based gene panel testing significantly reduces the time between onset and diagnosis. Methods: In order to assess the clinical utility of our custom NGS GHELP panel, the prevalence of pathogenic single nucleotide variants, indels or copy number variants was assessed by sequencing 171 nuclear and 8 mitochondrial genes in 155 Spanish individuals with hearing loss. Results: A genetic diagnosis of hearing loss was achieved in 34% (52/155) of the individuals (5 out of 52 were syndromic). Among the diagnosed cases, 87% (45/52) and 12% (6/52) associated with autosomal recessive and dominant inheritance patterns respectively; remarkably, 2% (1/52) associated with mitochondrial inheritance pattern. Although the most frequently mutated genes in this cohort were consistent with those described in the literature (GJB2, OTOF or MYO7A), causative variants in less frequent genes such as TMC1, FGF3 or mitCOX1 were also identified. Moreover, 5% of the diagnosed cases (3/52) were associated with pathogenic copy number variants. Conclusion: The clinical utility of NGS panels that allows identification of different types of pathogenic variants-not only single nucleotide variants/indels in both nuclear and mitochondrial genes but also copy number variants-has been demonstrated to reduce the clinical diagnostic odyssey in hearing loss. Thus, clinical implementation of genomic strategies within the regular clinical practice, and, more significantly, within the newborn screening protocols, is warranted.

Effects of paddles and fins on front crawl kinematics, arm stroke efficiency, coordination, and estimated energy cost.

Paddles and fins are used in swimmers training with different objectives (e.g., increase propulsive areas of hands and feet, improve the feeling of water flow). These artificial modifications of the stroke might be viewed as external constraints of the stroke task, both will either disturb or facilitate swimming modalities, so the coaches should manipulate its use to extract benefits for performance. This study seeks to investigate the precise effects of wearing either paddles (PAD) or fins (FINS) vs. a no-equipment (NE) trial in three all-out front crawl exercises on swimmer kinematics, arm stroke efficiency (ηp), upper-limbs coordination patterns (Index of Coordination, IdC), and estimated energy cost (C). Eleven regional to national-level male swimmers participated in the study (age: 25.8 ± 5.5 years, body mass: 75.2 ± 5.5 kg, height: 177 ± 6.5 cm) and were recorded from both sides of the swimming pool to collect all variables. Repeated measures ANOVA and Bonferroni post hoc were used to compare the variables. Effects sizes were calculated. Time to cover the distance and velocity were higher in FINS swimming, with larger values of stroke length (SL) and lower kick amplitude in comparison to the other trials (PAD and NE). The use of FINS also modified the stroke phases durations by presenting significant lower propulsion time during the stroke in comparison to PAD or NE. Values of IdC were lower (IdC < -1%, so catch-up pattern of coordination) for FINS in comparison to NE. In terms of ηp, using PAD or FINS demonstrate higher arm stroke efficiency than swimming without equipment. Finally, C was significantly higher in FINS swimming in comparison to NE and PAD. From the present results, it should be noted that the use of equipment such as fins deeply modify the structure of the swimming stroke (from the performance-related parameters through the kinematics of both upper and lower limbs to the stroke efficiency and coordination pattern). So, using equipment should be appropriately scaled by the coaches to the objectives of the training session in swimming, and in emergent sports such as "SwimRun", paddles and fins must be viewed as tools to achieve higher velocities to cover a given distance.

[Castleman-like presentation of systemic lupus: About a case report]. / Présentation « Castleman-like ¼ de lupus systémique : à propos d'un cas.

INTRODUCTION: Castleman disease is a rare lymphoproliferation, which may mimic systemic lupus. Conversely, systemic lupus sometimes presents like an hematological malignancy. In these cases, a "Castleman-like" histology has been exceptionally described. OBSERVATION: A 55-year-old female treated by methotrexate for systemic lupus with skin and joint involvement presented weight loss, polyadenopathy and clinical signs of lupus flare. Biology showed pancytopenia, complement activation, and positive anti-DNA antibodies. PET/CT showed hypermetabolic polyadenopathy. The lymph node biopsy showed "Castleman-like" features. Treatment with corticosteroids and azathioprine resulted in complete remission. CONCLUSION: Systemic lupus and Castleman disease may share common clinical, biological, and histological features. The presence of specific elements of systemic lupus flare and the remission obtained by low-dose corticosteroids results in considering the diagnosis of Castleman-like systemic lupus and avoiding treatment intensification.

Physical and rehabilitation medicine intervention in stroke in the acute hospital setting: A cross-sectional study / Intervención de la medicina física y de rehabilitación en el accidente cerebrovascular en el ámbito hospitalario agudo: un estudio transversal

Introduction: Stroke represents the main cause of death and disability in Portugal. Resulting functional deficits are widely recognized. This work aims to evaluate the variation in functionality of stroke patients in the acute hospital setting under a rehabilitation program. Material and methods: Cross-sectional study of patients admitted to the Neurology department, from January to June 2019, with acute stroke. The variation in functionality was assessed using the Barthel index. Statistical analysis used Student's t-test and Spearman's correlation coefficient, with a p-value≤0.05 as significant. Results: 106 patients with mean age of 63.7±14.2 years and a male predominance (60.4%) were included. Patients started rehabilitation program at 1.37±1.19 days after admission. A gain in functionality between admission and discharge was identified (50.18±32.37 versus 68.73±28.94, p<0.001). A significantly greater increase was observed in patients diagnosed under code stroke protocol (CSP) (p=0.021) and undergoing some type of acute phase treatment (p=0.017). From 90.5% of the patients that pursued rehabilitation after discharge, 40.6% were referred to an inpatient unit on average 12.7±7.0 days after admission. Discussion: In this study, Physical and Rehabilitation Medicine (PRM) provided early rehabilitation care to stroke patients. According to international evidence this is associated with greater functional gains. The variation in functionality verified during hospitalization demonstrates the importance of PRM in the acute hospital, assessing the rehabilitation needs after hospital discharge and maximizing outpatient rehabilitation. Diagnosis under CSP and undergoing acute treatment were determinants of greater functional improvement. Conclusion: PRM plays a central role in the early management of functional impairment resulting from stroke and in the post-discharge guidance of patients.(AU)

Introducción: El accidente cerebrovascular representa la principal causa de muerte y incapacidad en Portugal. Los déficits funcionales resultantes son ampliamente reconocidos. Este trabajo tiene como objetivo evaluar la variación en la funcionalidad de los pacientes con accidente cerebrovascular en el entorno hospitalario agudo bajo un programa de rehabilitación. Material y métodos: Estudio transversal de pacientes ingresados en el servicio de neurología, de enero a junio de 2019, con accidente cerebrovascular agudo. La variación en la funcionalidad se evaluó mediante el índice de Barthel. El análisis estadístico utilizó la prueba «t» de Student y el coeficiente de correlación de Spearman, con un valor p≤0,05 como significativo. Resultados: Se incluyeron 106 pacientes con edad media de 63,7±14,2 años y predominio del sexo masculino (60,4%). Los pacientes iniciaron el programa de rehabilitación a los 1,37±1,19 días después del ingreso. Se identificó una ganancia de funcionalidad entre el ingreso y el alta (50,18±32,37 versus 68,73±28,94, p<0,001). Se observó un aumento significativamente mayor en los pacientes diagnosticados bajo el protocolo de ictus (p=0,021) y sometidos a algún tipo de tratamiento en fase aguda (p=0,017). Del 90,5% de los pacientes que continuaron rehabilitación tras el alta, el 40,6% fueron derivados a una unidad de rehabilitación, en promedio 12,7±7,0 días después del ingreso. Discusión: En este estudio la medicina física y de rehabilitación (MFR) proporcionó atención de rehabilitación temprana a pacientes con accidente cerebrovascular. Según la evidencia internacional esto se asocia con mayores ganancias funcionales. La variación en la funcionalidad verificada durante la hospitalización demuestra la importancia de la MFR en el hospital de agudos, evaluando las necesidades de rehabilitación después del alta hospitalaria y maximizando la rehabilitación ambulatoria.(AU)

Physical and rehabilitation medicine intervention in stroke in the acute hospital setting: A cross-sectional study.

INTRODUCTION: Stroke represents the main cause of death and disability in Portugal. Resulting functional deficits are widely recognized. This work aims to evaluate the variation in functionality of stroke patients in the acute hospital setting under a rehabilitation program. MATERIAL AND METHODS: Cross-sectional study of patients admitted to the Neurology department, from January to June 2019, with acute stroke. The variation in functionality was assessed using the Barthel index. Statistical analysis used Student's t-test and Spearman's correlation coefficient, with a p-value≤0.05 as significant. RESULTS: 106 patients with mean age of 63.7±14.2 years and a male predominance (60.4%) were included. Patients started rehabilitation program at 1.37±1.19 days after admission. A gain in functionality between admission and discharge was identified (50.18±32.37 versus 68.73±28.94, p<0.001). A significantly greater increase was observed in patients diagnosed under code stroke protocol (CSP) (p=0.021) and undergoing some type of acute phase treatment (p=0.017). From 90.5% of the patients that pursued rehabilitation after discharge, 40.6% were referred to an inpatient unit on average 12.7±7.0 days after admission. DISCUSSION: In this study, Physical and Rehabilitation Medicine (PRM) provided early rehabilitation care to stroke patients. According to international evidence this is associated with greater functional gains. The variation in functionality verified during hospitalization demonstrates the importance of PRM in the acute hospital, assessing the rehabilitation needs after hospital discharge and maximizing outpatient rehabilitation. Diagnosis under CSP and undergoing acute treatment were determinants of greater functional improvement. CONCLUSION: PRM plays a central role in the early management of functional impairment resulting from stroke and in the post-discharge guidance of patients.

Noncompliance to iodine supplementation recommendation is a risk factor for iodine insufficiency in Portuguese pregnant women: results from the IoMum cohort.

PURPOSE: After a recommendation for iodine supplementation in pregnancy has been issued in 2013 in Portugal, there were no studies covering iodine status in pregnancy in the country. The aim of this study was to assess iodine status in pregnant women in Porto region and its association with iodine supplementation. METHODS: A cross-sectional study was conducted at Centro Hospitalar Universitário São João, Porto, from April 2018 to April 2019. Pregnant women attending the 1st trimester ultrasound scan were invited to participate. Exclusion criteria were levothyroxine use, gestational age < 10 and ≥ 14 weeks, non-evolutive pregnancy at recruitment and non-signing of informed consent. Urinary iodine concentration (UIC) was measured in random spot urine by inductively coupled plasma-mass spectrometry. RESULTS: Median UIC was 104 µg/L (IQR 62-189) in the overall population (n = 481) of which 19% had UIC < 50 µg/L. Forty three percent (n = 206) were not taking an iodine-containing supplement (ICS) and median UIC values were 146 µg/L (IQR 81-260) and 74 µg/L (IQR 42-113) in ICS users and non-users, respectively (p < 0.001). Not using an ICS was an independent risk factor for iodine insufficiency [adjusted OR (95% CI) = 6.00 (2.74, 13.16); p < 0.001]. Iodised salt use was associated with increased median iodine-to-creatinine ratio (p < 0.014). CONCLUSIONS: A low compliance to iodine supplementation recommendation in pregnancy accounted for a mild-to-moderately iodine deficiency. Our results evidence the need to support iodine supplementation among pregnant women in countries with low household coverage of iodised salt. Trial registration number NCT04010708, registered on the 8th July 2019.

Van der Waals materials as dielectric layers for tailoring the near-field photonic response of surfaces.

Epsilon near-zero photonics and surface polariton nanophotonics have become major fields within optics, leading to unusual and enhanced light-matter interaction. Specific dielectric responses are required in both cases, which can be achieved, e.g., via operation near a material's electronic or phononic resonance. However, this condition restricts operation to a specific, narrow frequency range. It has been shown that using a thin dielectric layer can adjust the dielectric response of a surface and, therefore, the operating frequency for achieving specific photonic excitations. Here, we show that a surface's optical properties can be tuned via the deposition/transference of ultra-thin layered van der Waals (vdW) crystals, the thicknesses of which can easily be adjusted to provide the desired response. In particular, we experimentally and theoretically show that the surface phonon resonance of a silica surface can be tuned by ∼50 cm-1 through the simple deposition of nanometer-thick exfoliated flakes of black phosphorus. The surface properties were probed by infrared nanospectroscopy, and results show a close agreement with the theory. The black phosphorus-silica layered structure effectively acts as a surface with a tunable effective dielectric constant that presents an infrared response dependent on the black phosphorus thickness. In contrast, with a lower dielectric constant, hexagonal boron nitride does not significantly tune the silica surface phonon polariton. Our approach also applies to epsilon near-zero surfaces, as theoretically shown, and to polaritonic surfaces operating at other optical ranges.

Úlceras vulvares: un reto diagnóstico / Vulvar ulcers: A diagnostic challenge

Las úlceras vulvares son una entidad patológica relevante por su repercusión en la calidad de vida de la mujer y suponen un desafío diagnóstico dada la variedad etiológica y de presentación clínica. El diagnóstico se basa en la anamnesis, la exploración física detallada y pruebas complementarias.Presentamos el caso clínico de una paciente de 39 años con diagnóstico de úlceras vulvares graves, recidivantes, que requirió ingreso hospitalario prolongado en tres ocasiones. Se describe el proceso de identificación, los posibles diagnósticos diferenciales y el resultado del tratamiento aplicado.(AU)

Vulvar ulcers are an important pathological condition due to their impact on the quality of life of women. It is a diagnostic challenge given the aetiological variety and clinical presentation. The diagnosis is based on anamnesis, detailed physical examination, and complementary tests.The clinical case is presented of a 39-year-old patient diagnosed with severe, recurrent vulvar ulcers, and who required prolonged hospital admission on three occasions. The diagnostic process, possible differential diagnoses, and the outcome of the applied treatment are described.(AU)

Sulfadiazine removal using green zero-valent iron nanoparticles: A low-cost and eco-friendly alternative technology for water remediation.

In this work, the effectiveness of green zero-valent iron nanoparticles (gnZVIs) for the removal of the antibiotic sulfadiazine (SDZ) from water via adsorption and reduction was tested. Additionally, the effectiveness of this material as a catalyst for the Fenton and photo-Fenton processes was also investigated. This represents the first study concerning the use of gnZVIs for the degradation of a sulfonamide antibiotic. The results obtained indicate that gnZVIs were able to remove up to 58% of SDZ via adsorption and up to 69% via adsorption plus reduction using a SDZ/Fe3+ molar ratio of 1:61.6. Furthermore, gnZVIs showed strong effectiveness as a catalyst for the Fenton and photo-Fenton reactions, with complete SDZ removal in 8 h and 5 min, respectively, using a SDZ/Fe3+/H2O2 molar ratio of 1:38.4:38.4. These results demonstrate that the use of gnZVIs constitutes an attractive and potential alternative technology for water remediation, reducing environmental impact and operational costs.

Effects of single and combined exposures of gold (nano versus ionic form) and gemfibrozil in a liver organ culture of Sparus aurata.

In vitro methods have gained rising importance in ecotoxicology due to ethical concerns. The aim of this study was to assess the single and combined in vitro effects of gold, as nanoparticle (AuNPs) and ionic (Au+) form, and the pharmaceutical gemfibrozil (GEM). Sparus aurata liver organ culture was exposed to gold (4 to 7200 µg·L-1), GEM (1.5 to 15,000 µg·L-1) and combination 80 µg·L-1 gold +150 µg·L-1 GEM for 24 h. Endpoints related with antioxidant status, peroxidative/genetic damage were assessed. AuNPs caused more effects than Au+, increasing catalase and glutathione reductase activities and damaging DNA and cellular membranes. Effects were dependent on AuNPs size, coating and concentration. GEM damaged DNA at an environmentally relevant concentration, 1.5 µg·L-1. Overall, the effects of the combined exposures were higher than the predicted, based on single exposures. This study showed that liver culture can be a useful model to study contaminants effects.

The effect of climate change on domestic Rainwater Harvesting.

One of the main strategies that are being applied to improve the efficiency of water consumption in buildings is the use of non-potable water for pavement washing, toilet flushing, irrigation, and others. According to several guidelines, the design and assessment of a Rainwater Harvesting System (RWHS) should be made using recent official records of precipitation. However, there is not an indication whether historical or future projections should be used, leaving space for the designer to choose. This article presents the study of RWHS in southern Europe, namely in Portugal, considering two case studies (a dwelling in Oporto and an apartment in Vila Real). The main goal was to explore the impacts that climate change will have on these systems and, for that purpose, a daily simulation using future rainfall data was performed for both cases considering two scenarios: RCP 4.5 which is more optimistic, and RCP 8.5 which is more pessimistic. The RWHS in Oporto showed a better performance in the future decades, comparing with simulations based on recent decades, for both scenarios. However, the savings will not have a significant variation (less than 5 €/year). In the future, this system will provide around 47 (±2.4) m3 of rainwater per year to the selected non-potable purposes, leading to savings of around 66 (±3.3) €/year. Vila Real case study also revealed a slight improvement of the system's efficiency in the future decades but the results for rainwater collected and used are so similar to the recent ones that it can be concluded that the performance will be sustained. This system will provide around 50 (±2.5) m3 of rainwater per year to the selected non-potable purposes, leading to savings of around 200 (±10.2) €/year. It can be concluded that there will be no significant changes in RWHS performance in the future, in the studied areas.

Does Quorum Sensing play a role in microbial shifts along spontaneous fermentation of cocoa beans? An in silico perspective.

Cocoa fermentation is a spontaneous process shaped by a variable microbial ecosystem which is assembled due to cross-feeding relationship among yeasts and bacteria, resulting in a synchronized microbial succession started by yeasts, followed by lactic acid bacteria (LAB) and finalized by acetic acid bacteria (AAB). Several studies have indicated the effect of microbial interactions in food ecosystems highlighting the importance of quorum sensing (QS) in bacterial adaptation in harsh environments modulating several phenotypes such as biofilm formation, tolerance to acid stress, bacteriocin production, competence, morphological modifications, motility, among others. However, antagonic interactions also occur, and can be marked by Quorum Quenching (QQ) activity, negatively impacting QS regulated phenotypes. Our current knowledge regarding microbial cocoa composition and functioning is based on culture-based analysis and culture-independent PCR-based methods. Therefore, we set out to investigate the application of metagenomics analysis on a classical spontaneous cocoa fermentation in order to describe: (I) the microbial taxonomic composition; (II) the functional potential of the cocoa microbiome; (III) the microbiome putative QS potential; and (IV) the microbiome QQ potential. Both aims III and IV are related to the expression of effectors that may confer advantageous traits along fermentation which can explain their dominance in specific time zones during the entire process. We have observed a bacterial succession shaped by yeasts and filamentous fungi and then Enterobacteriaceales, LAB and AAB, as well as a diverse genetic metabolic potential related to proteins and carbohydrates metabolism associated to the yeast Saccharomyces cerevisiae and members of the Enterobacteriaceales order and LAB and AAB groups. In addition, in silico evidences of interspecific QS arsenal were found in members of the genera Enterobacter, Lactobacillus, Bacillus and Pantoea, while inferences of intraspecific QS potential were found in the members of the genera Bacillus, Enterobacter, Komagataeibacter, Lactobacillus and Pantoea. In addition, a QQ potential was detected in Lactobacillus and in AAB members. These findings indicate that QS and QQ may modulate bacterial dominance in different time points during fermentation, along with cross-feeding, being responsible for their maintenance in a large time range.

Do Workers from Subspecies Acromyrmex subterraneus Prepare Leaves and Toxic Baits in Similar Ways for Their Fungus Garden?

Toxic baits are the most efficient method to control leaf-cutter ants in eucalyptus forests for paper and cellulose production. For the proper use of these baits, insecticide compounds must reach workers and contaminate them. Thus, understanding how these baits are processed inside the nests is vital for a successful control, especially when it comes to genus Acromyrmex. Lack of information on toxic baits and on contamination of Acromyrmex workers raises the question: do workers from subspecies Acromyrmex subterraneus (Forel) prepare leaves and toxic baits in similar ways for their fungus garden? To answer it, this study described and analyzed the behavioral repertoire executed by A. subterraneus workers during the preparation of leaf disks and baits and their incorporation into the fungus garden. Results show that the act of licking the substrate was the most frequently executed behavior, regardless of subspecies or size categories. Moreover, additional behaviors have been observed when workers processed the baits, such as licking and scraping their jaws on the surface of the bait pellet, as well as licking and biting fragments of bait pellets, moistening them. Thus, it is concluded that the preparation of baits is different from that of leaves; baits are more processed and can therefore contribute to contaminating workers via insecticides.

Electrochemical impedance spectroscopy characterization of beverages.

This paper compares the results of standard chemical analytical processes and electrochemical impedance spectroscopy (EIS) in the characterization of different beverages, namely ground coffee, soluble coffee, coffee substitutes, barley, cow milk, vegetable drinks, tea, plant infusions and plant mixtures. For the two approaches, the similarities between the experimental data are assessed by means of the Euclidean and Canberra distances. The resulting information is processed by means of the multidimensional scaling (MDS) clustering and visualization algorithm. The results of the chemical analytical processes and EIS reveal identical clusters for the two adopted distances. Furthermore, the robustness of the experimental and computational scheme are assessed by means of the Procrustes technique. The results confirm the effectiveness of combining the EIS and MDS.

Fe3O4@Au nanoparticles-based magnetoplatform for the HMGA maize endogenous gene electrochemical genosensing.

This work addresses a technological advance applied to the construction of a magnetogenoassay with electrochemical transduction for the maize taxon-specific (HMGA gene) detection using gold-coated magnetic nanoparticles as nanosized platform. Superparamagnetic core-shell Fe3O4@Au nanoparticles (10.4 ±â€¯1.7 nm) were used to assemble the genoassay through the covalent immobilization of HMGA DNA probes onto carboxylated self-assembled monolayers at the nanoparticles surface. A hybridization reaction using sandwich format was selected to prevent inefficient hybridization connected with stable secondary DNA structures using also fluorescein isothiocyanate as DNA signaling tag. The labelling of the hybridization reaction with enzymes allowed the chronoamperometric measurement of the peroxidase activity linked to the nanoplatform located on gold surface. Using this electrochemical magnetogenoassay a linear concentration range from 0.5 to 5 nM and a LOD of 90 pM with a RSD <1.2% was calculated. Certified maize was evaluated without further purification after PCR amplification. This work highlights the efficacy of the electrochemical magnetogenoassay for the HMGA detection, showing its potential as alternative procedure for the verification of the compliance of the legislation.

Preconcentration and sensitive determination of the anti-inflammatory drug diclofenac on a paper-based electroanalytical platform.

This work describes the development of a paper-based platform for highly sensitive detection of diclofenac. The quantification of this anti-inflammatory drug is of importance in clinical (e.g. quality and therapeutic control) and environmental (e.g. emerging contaminant determination) areas. The easy-to-handle platform here described consists of a carbon-ink paper-based working electrode and two metallic wires, provided by a gold-plated standard connector, as reference and counter electrodes. The porous paper matrix enables the preconcentration of the sample, decoupling sample and detection solutions. Thus, relatively large sample volumes can be used, which significantly improves the sensitivity of the method. A wide dynamic range of four orders of magnitude, between 0.10 and 100 µM, was obtained for diclofenac determination. Due to the predominance of adsorption at the lowest concentrations, there were two linear concentration ranges: one comprised between 0.10 and 5.0 µM (with a slope of 0.85 µA µM-1) and the other between 5.0 and 100 µM (with a slope of 0.48 µA µM-1). A limit of detection of 70 nM was achieved with this simple device that provided accurate results with an RSD of ca. 5%. The platform was applied for diclofenac quantification in spiked tap water samples. The versatility of this design enabled the fabrication of a multiplexed platform containing eight electrochemical cells that work independently. The low cost, small size and simplicity of the device allow on-site analysis, which is very useful for environmental monitoring.