From glow-sticks to sensors: Single-electrode electrochemical detection for paper-based devices

With the goal of creating a multipurpose platform for electrogenerated luminescence, a single electrode electrochemical system was designed, developed, and validated. Glow sticks were used as the source of the luminophore, which was used as the optical reporter for the biosensor. A smartphone was used as the detector to quantify the electrochemiluminescence emissions. A disposable paper-based device was designed and used as a two-compartment electrochemical reaction cell, affording the possibility to individually optimize the sensing and detection reactions. This sensor assembly was tested under different conditions, showing acceptable performance both in the determination of hydrogen peroxide concentrations, to evaluate rancidity markers in edible oil samples, and to quantify the glucose concentration in soft drinks. The analytical performance of the single electrode, electrochemiluminescent device showed a limit of detection for hydrogen peroxide of 1.02 µM, with a working range between 0.4 µM and 150 mM. The proposed approach represents the first example of a system that combines paperbased devices, single electrode electrochemistry, electrochemiluminescence, and smartphone image sensing. As such, it not only provides a convenient platform for the development of a variety of analytical applications but also broaden the versatility of ePADs.Fil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Whitehead, Daniel C.. CLEMSON UNIVERSITY (CLEMSON UNIVERSITY);Fil: Garcia, Carlos D.. CLEMSON UNIVERSITY (CLEMSON UNIVERSITY)

Native Fluorescent Natural Deep Eutectic Solvents for Green Sensing Applications: Curcuminoids in Curcuma longa Powder

Natural deep eutectic solvents are a trending topic in Green Chemistry. These solvents present high solubilization capacity, reusability, tunable properties, simple preparation, biodegradability, safety, high availability, and low cost, making them excellent candidates for analytical applications. In this work, a new family of fluorescent eutectic systems is described, with the fluorescence property being unknown and unused so far. For this purpose, a novel preparation method using an ultrasound probe was employed, by means of an innovative single-step procedure, that included the preparation of FCH (fructose, citric acid, and water, 1:1:5 molar ratio) and the extraction/determination of curcuminoids from Curcuma longa powder. This methodology was successfully carried out by employing a portable and inexpensive 3D-printed fluorometer and a smartphone. In this way, extraction efficiencies between 90 and 106%, relative to the NIST reference method, were obtained in just 3.40 min. Besides, the greenness of the new methodology was evaluated by employing the AGREE metric, showing that the developed approach is >2.5 times greener than previously published works for curcuminoid determination. This groundbreaking procedure is robust, versatile, and simple to implement, does not require sophisticated apparatus or instruments in the detection step, and, mainly, agrees with Green Analytical Chemistry (GAC) principles.Fil: Lorenzetti, Anabela Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Gomez, Federico Jose Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin

Distinctive Signals in 1‐minute Observations of Overshooting Tops and Lightning Activity in a Severe Supercell Thunderstorm

This work examines a severe weather event that took place over central Argentina on 11 December 2018. The evolution of the storm from its initiation, rapid organization into a supercell, and eventual decay was analyzed with high-temporal resolution observations. This work provides insight into the spatio-temporal co-evolution of storm kinematics (updraft area and lifespan), cloud-top cooling rates, and lightning production that led to severe weather. The analyzed storm presented two convective periods with associated severe weather. An overall decrease in cloud-top local minima IR brightness temperature (MinIR) and lightning jump (LJ) preceded both periods. LJs provided the highest lead time to the occurrence of severe weather, with the ground-based lightning networks providing the maximum warning time of around 30 min. Lightning flash counts from the Geostationary Lightning Mapper (GLM) were underestimated when compared to detections from ground-based lightning networks. Among the possible reasons for GLM's lower detection efficiency were an optically dense medium located above lightning sources and the occurrence of flashes smaller than GLM's footprint. The minimum MinIR provided the shorter warning time to severe weather occurrence. However, the secondary minima in MinIR that preceded the absolute minima improved this warning time by more than 10 min. Trends in MinIR for time scales shorter than 6 min revealed shorter cycles of fast cooling and warming, which provided information about the lifecycle of updrafts within the storm. The advantages of using observations with high-temporal resolution to analyze the evolution and intensity of convective storms are discussed.Fil: Borque, Paloma Celina. University of Illinois. Urbana - Champaign; Estados Unidos. Pacific Northwest National Laboratory; Estados UnidosFil: Vidal, Luciano. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rugna, Martin Ezequiel. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; ArgentinaFil: Lang, Timothy J.. National Aeronautics and Space Administration; Estados UnidosFil: Nicora, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; ArgentinaFil: Nesbitt, Stephen William. University of Illinois. Urbana - Champaign; Estados Unido

Proteomic Profile Associated With Loss of Spontaneous Human Immunodeficiency Virus Type 1 Elite Control

[Background] Elite controllers (ECs) spontaneously control plasma human immunodeficiency virus type 1 (HIV-1) RNA without antiretroviral therapy. However, 25% lose virological control over time. The aim of this work was to study the proteomic profile that preceded this loss of virological control to identify potential biomarkers.[Methods] Plasma samples from ECs who spontaneously lost virological control (transient controllers [TCs]), at 2 years and 1 year before the loss of control, were compared with a control group of ECs who persistently maintained virological control during the same follow-up period (persistent controllers [PCs]). Comparative plasma shotgun proteomics was performed with tandem mass tag (TMT) isobaric tag labeling and nanoflow liquid chromatography coupled to Orbitrap mass spectrometry.[Results] Eighteen proteins exhibited differences comparing PC and preloss TC timepoints. These proteins were involved in proinflammatory mechanisms, and some of them play a role in HIV-1 replication and pathogenesis and interact with structural viral proteins. Coagulation factor XI, α-1-antichymotrypsin, ficolin-2, 14-3-3 protein, and galectin-3-binding protein were considered potential biomarkers.[Conclusions] The proteomic signature associated with the spontaneous loss of virological control was characterized by higher levels of inflammation, transendothelial migration, and coagulation. Galectin-3 binding protein could be considered as potential biomarker for the prediction of virological progression and as therapeutic target in ECs.This work was supported by grants from the Fondo de Investigación Sanitaria, Instituto de Salud Carlos III, Fondos Europeos para el Desarrollo Regional (grant numbers PI10/02635, PI13/00796, and PI16/00503 to F. V.; PI12/02283, PI16/00684, and CPII014/00025 to E. R.-M.; FI14/00431 to L. T.-D.; and CP14/00198 to N. R.); Programa de Suport als Grups de Recerca (grant numbers 2017SGR948 and 2014SGR250); the Gilead Fellowship Program (grant numbers GLD14/293 and GLD17/00299); the Red de Investigación en Sida (grant numbers RD12/0017/0005, RD16/0025/0006, RD12/0017/0029, RD16/0025/0020, and RD12/0017/0031, RD16/0025/0013); Ministerio de Economia y Competitividad, Spain (grant number SAF2015-66193-R); and the Spanish Ministry of Education (grant number FPU13/02451 to B. D. M). E. R.-M. is supported by Consejería de Salud y Bienestar Social of Junta de Andalucía through the Nicolás Monardes program (C-0032/17). F. V. is supported by a grant from the Programa de Intensificación de Investigadores, Instituto de Salud Carlos III (grant numbers INT11/240, INT12/282, and INT15/226). A. R. is supported by a grant from the Acció Instrumental d’incorporació de científics i tecnòlegs (PERIS SLT002/16/00101), Departament de Salut, Generalitat de Catalunya.Peer reviewe

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

3D-printed device for the kinetic determination of As(III) in groundwater samples by digital movie analysis

High concentrations of inorganic arsenic in groundwater for human consumption is a worldwide common problem. Particularly, the determination of As(III) becomes important, since this species is more toxic than organic, pentavalent and elemental arsenic forms. In this work, a 3D-printed device that included a 24-well microplate was developed to perform the colourimetric kinetic determination of arsenic (III) by digital movie analysis. A smartphone camera attached to the device was used to take the movie during the process where As(III) inhibited the decolourization of methyl orange. The movie images were subsequently transformed from RGB to YIQ space to obtain a new analytical parameter called “d”, which was related to the chrominance of the image. Then, this parameter allowed the determination of the inhibition time of reaction (tin), which was linearly correlated with the concentration of As(III). A linear calibration curve (R = 0.9995) in the range from 5 μg L−1 to 200 μg L−1 was obtained. The method was precise (RSD = 1.2%), and the limits of detection (LOD) and quantification (LOQ) were 1.47 μg L−1 and 4.44 μg L−1, respectively. These values were lower than the limit established by the World Health Organization for total arsenic in drinking water (10 μg L−1). The accuracy of the method was assessed by a recovery study with optimal results (94.3%–104.0%). Additionally, the Analytical GREEnness metric approach was applied, obtaining a score 1.7 times higher than previously published works. The method is simple, portable and low-cost, being in compliance with various principles of green analytical chemistry.Fil: Nario, Nicolás Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Grunhut, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin

Use of universal 3D-Printed smartphone spectrophotometer to develop a time-based analysis for hypochlorite

A fully-functional smartphone-based spectrophotometer was designed and built using 3D printing. The major advantage of this approach is its capacity to be interfaced with a variety of smartphones, allowing the use of the smartphone's camera and display, and regardless of the relative position of the camera. The analytical performance of the device was analyzed using a model dye (crystal violet), leading to a proportional response for concentrations in the 0.06–15.0 mg L−1 range, with a variability of 1.0% (intra-day) and 2.6% (inter-day). To demonstrate the functionality of the device, the degradation process of the dye by sodium hypochlorite was studied. The results obtained were applied to develop a paper-based test for NaClO in sanitation solutions, in which the time required to bleach the dye was used to estimate the concentration of the solution. This device represents a simple and inexpensive tool for everyday laboratory use and could address important analytical challenges in low-income communities and features a versatile arrangement, that is compatible with a wide variety of smartphones and software platforms.Fil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Lorenzetti, Anabela Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Garcia, Carlos D.. Clemson University; Estados UnidosFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin

Micropaper-based analytical device (μPAD) for the simultaneous determination of nitrite and fluoride using a smartphone

The design, optimization and evaluation of a micro paper-based analytical device (μPAD) for the simultaneous determination of fluoride and nitrite in real water samples was developed. In order to create hydrophilic and hydrophobic zones on the laboratory filter paper device, a wax ink printer was used. The μPAD has four reaction zones for each analyte where the respective colorimetric reactions took place using the SPADNS method and Griess method for fluoride and nitrite respectively. A Smartphone was used to capture the corresponding images which were then converted to the RGB colour space by the software ImageJ using a personal computer. Under the optimal conditions, the linear range was 0.23–2.26 mg L−1 for fluoride with limit of detection (LOD) and limit of quantification (LOQ) of 0.13 mg L−1 and 0.25 mg L−1. The working range for nitrite was 0.05–10.0 mg L−1 with LOD of 0.03 mg L−1 and LOQ 0.13 mg L−1. The μPAD was used to determine the analytes in water samples obtaining satisfactory results in both cases. The validation of fluoride determination was performed comparing the μPAD with the reference method and for nitrite determination, a recovery study was carried out. In both cases, the obtained results demonstrated a good agreement.Fil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Lorenzetti, Anabela Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Lista, Adriana Guillermina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin

Flow injection analysis: Rayleigh light scattering technique for total protein determination

A novel flow injection analysis (FIA) method with Rayleigh light scattering (RLS) detection was developed for the determination of total protein concentrations. This method is based on the weak intensity of RLS of bromothymol blue (BB) (3′,3″-dibromothymolsulfonephthalein) which can be enhanced by the addition of protein in weakly acidic solution. A common spectrofluorimeter was used as a detector. It was proved that the application of this method to quantify the total proteins in real samples by using bovine serum albumin was possible. The RLS signal was detected at λ ex=λ em=572 nm. The linear range was 7.0-70.0 μg mL-1, the detection limit was 3.75 μg mL-1, the reproducibility was 5.5% (n=7), and the sample throughput was 26 h-1.Fil: Vidal, Ezequiel Martin. Universidad Nacional del Sur. Departamento de Química. Química Analítica; ArgentinaFil: Palomeque, Miriam Edid. Universidad Nacional del Sur. Departamento de Química. Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Lista, Adriana Guillermina. Universidad Nacional del Sur. Departamento de Química. Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Fernández Band, Beatriz Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur. Departamento de Química. Química Analítica; Argentin

New, inexpensive and simple 3D printable device for nephelometric and fluorimetric determination based on smartphone sensing

A new, inexpensive and easy to use 3D printable device was developed for nephelometric and fluorimetric determination. Its applicability was tested for the quantification of quinine in tonic drinks and sulfate in natural water with good analytical accuracy. In this way, sulfate determination was carried out by nephelometry using a red LED, while quinine was determined using a blue LED by fluorimetry. A smartphone camera was used to take the pictures and afterwards transform them into the RGB color space using the software ImageJ by a personal computer. The linear range was 2.0-50.0 mg L-1for sulfate with a LOD of 0.13 mg L-1, and the corresponding quantification limit (LOQ) was 0.43 mg L-1. The linear range for quinine was from 0.42 to 3.10 mg L-1. The LOD and LOQ were 0.11 mg L-1and 0.38 mg L-1, respectively.Fil: Vidal, Ezequiel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Lorenzetti, Anabela Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Aguirre, Miguel Ángel. Universidad de Alicante; EspañaFil: Canals, Antonio. Universidad de Alicante; EspañaFil: Domini, Claudia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentin