Dispositivo de lectura de microarrays de tipo eléctrico y reutilizable

Dispositivo de lectura de microarrays de tipo eléctrico y reutilizable. El objeto principal de la presente invención es un dispositivo de lectura eléctrica de microarrays que se puede limpiar y volver a utilizar más de una vez. El dispositivo (1, 1’, 1”) de lectura de microarrays (6) tiene las siguientes partes: una base (2, 2’, 2”), que tiene unos medios de apoyo (3, 3’, 3”) para situar la superficie de test (7) del microarray (6) en paralelo a una superficie de lectura (4) de la base (2, 2’, 2”); una matriz de transductores (5, 5’, 5”), dispuestos sobre la superficie de lectura (4) de la base (2, 2’, 2”), que traducen una variación de una magnitud eléctrica o química en una variación de una magnitud eléctrica; y unos medios de lectura (10), conectados a los transductores (5, 5’, 5”), que interpretan las señales eléctricas de los transductores (5, 5’, 5”).Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patentes con informe sobre el estado de la técnic

Rapid colorimetric detection of wound infection with a fluidic paper device

Current procedures for the assessment of chronic wound infection are time-consuming and require complex instruments and trained personnel. The incidence of chronic wounds worldwide, and the associated economic burden, urge for simple and cheap point-of-care testing (PoCT) devices for fast on-site diagnosis to enable appropriate early treatment. The enzyme myeloperoxidase (MPO), whose activity in infected wounds is about ten times higher than in non-infected wounds, appears to be a suitable biomarker for wound infection diagnosis. Herein, we develop a single-component foldable paper-based device for the detection of MPO in wound fluids. The analyte detection is achieved in two steps: (i) selective immunocapture of MPO, and (ii) reaction of a specific dye with the captured MPO, yielding a purple color with increasing intensity as a function of the MPO activity in infected wounds in the range of 20–85 U/mL. Ex vivo experiments with wound fluids validated the analytic efficiency of the paper-based device, and the results strongly correlate with a spectrophotometric assay.Peer ReviewedPostprint (published version

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

Time to Switch to Second-line Antiretroviral Therapy in Children With Human Immunodeficiency Virus in Europe and Thailand.

Background: Data on durability of first-line antiretroviral therapy (ART) in children with human immunodeficiency virus (HIV) are limited. We assessed time to switch to second-line therapy in 16 European countries and Thailand. Methods: Children aged <18 years initiating combination ART (≥2 nucleoside reverse transcriptase inhibitors [NRTIs] plus nonnucleoside reverse transcriptase inhibitor [NNRTI] or boosted protease inhibitor [PI]) were included. Switch to second-line was defined as (i) change across drug class (PI to NNRTI or vice versa) or within PI class plus change of ≥1 NRTI; (ii) change from single to dual PI; or (iii) addition of a new drug class. Cumulative incidence of switch was calculated with death and loss to follow-up as competing risks. Results: Of 3668 children included, median age at ART initiation was 6.1 (interquartile range (IQR), 1.7-10.5) years. Initial regimens were 32% PI based, 34% nevirapine (NVP) based, and 33% efavirenz based. Median duration of follow-up was 5.4 (IQR, 2.9-8.3) years. Cumulative incidence of switch at 5 years was 21% (95% confidence interval, 20%-23%), with significant regional variations. Median time to switch was 30 (IQR, 16-58) months; two-thirds of switches were related to treatment failure. In multivariable analysis, older age, severe immunosuppression and higher viral load (VL) at ART start, and NVP-based initial regimens were associated with increased risk of switch. Conclusions: One in 5 children switched to a second-line regimen by 5 years of ART, with two-thirds failure related. Advanced HIV, older age, and NVP-based regimens were associated with increased risk of switch

A wireless LC chemical sensor based on a high quality factor EIS capacitor

This paper reports on the concept, design, fabrication andexperimental results of a new passive wireless sensor for pH measurements. Thesensor is based on a LC resonator formed by an inductor and an EIS (Electrolyte-Insulator-Silicon) capacitor working as a pH-to-capacitance transductor. Areference electrode is used to obtain a stable DC potential at the electrolyte.An additional comb-like electrode located on the surface of the insulator isalso provided to obtain a low AC impedance. Using this double-electrode scheme aQ larger than 15 is achieved for a wide range of conductivities. wireless measurements of the LC sensor yields a sensitivity of 1.0% frequency change perpH unit.MEC-DGI Ref: TEC2004-00068 (MIQUIN)Peer reviewe

A microstructured silicon membrane with entrapped hydrogels for environmentally sensitive fluid gating

In this paper, we report on the fabrication and characterization of a new hydrogel-basedmicrovalve. The basic structure is a silicon membrane having an array of orifices with aninternal structure designed to anchor the hydrogel while allowing it to gate the flow across themembrane. Each orifice (140μm diameter) has a central post suspend by four tethers on eachside of the membrane. A stimuli-sensitive hydrogel is polymerized inside each orifice. In theswollen state, the hydrogel completely occupies the void space of the orifice, completelyblocking pressure-driven fluid flow. In the shrunken state, the hydrogel contracts around thepost, allowing fluid to flow through an opened annular gap. Fabrication of the microstructuredsilicon membrane requires only two masking steps and involves a combination of deep trenchand KOH etch. Two different hydrogels, based on N-isopropylacrylamide (temperaturesensitive)and phenylboronic acid (pH and glucose-sensitive) were trapped and tested in thismicrovalve. The measured response times were 10 seconds (temperature), 4 minutes (pH), and10 minutes (glucose). The maximum pressure drop the microvalve can sustain before breakageof the hydrogel is 21 and 16kPa for temperature-sensitive and (pH/glucose)-sensitive hydrogels,respectively.Peer reviewe

A hydrogel-actuated environmentally sensitive microvalve for active flow control

This paper reports on the fabrication and test of a hydrogel-actuated microvalve that responds tochanges in the concentration of specific chemical species in an external liquid environment. Themicrovalve consists of a thin hydrogel, sandwiched between a stiff porous membrane and a flexiblesilicone rubber diaphragm. Swelling and deswelling of the hydrogel, which results from the diffusion ofchemical species through the porous membrane is accompanied by the deflection of the diaphragm andhence closure and opening of the valve intake orifice. A phenylboronic acid based hydrogel was used toconstruct a smart microvalve that responds to the changes in the glucose and pH concentrations. Thefastest response time (for a pH concentration cycle) achieved was 7 minutes using a 30 μm thick hydrogeland a 60 μm thick porous membrane with 0.1 μm pore size and 40% porosity.Peer reviewe

Système de biocapteur pour la détection de biomarqueurs multiplexée

The invention refers to a biosensor system for quick and multiplexed detection of biomarkers present in biological fluids. The biosensor system comprises a reusable array of at least two individual electrochemical cells (1a,1b,1c,1d,1e) coupled to a disposable fluidic component. Each cell can be addressed individually. The array includes a set of working electrodes (2a,2b,2c,2d) and at least one shared counter/reference electrode (5) in common for all the electrochemical cells, such that each electrochemical cell includes one working electrode and the shared counter/reference electrode. Preferably, the system includes a disposable paper component (8) having a reactive microfluidic component distributed in fluidic channels (9), isolated by hydrophobic barriers (10). The paper component (8) is operatively aligned with the array of electrochemical cells for the electrochemical detection by means of a polymeric cartridge. The multiplexed biosensor system features a reduced size, and that allows reduction of analysis costs and material waste.NoConsejo Superior de Investigaciones Científicas (CSIC)A1 Solicitud de patente con informe sobre el estado de la técnic

Sensor de iones de medida diferencial

[EN] The invention relates to an ion sensor with differential measurement, which, by means of at least two ion-selective field effect transistors, compares the concentration of determined ions in a solution to be measured with the concentration of determined ions in a reference solution confined in a microreservoir with a microchannel. To this end, the microreservoir and the microchannel cover at least the gate of one of the ion-selective field effect transistors, and form part of an assembly partially filled with a porous material covering said entire gate and at least the base of the microchannel.[ES] La presente invención se refiere a un sensor de iones de medida diferencial, que mediante al menos dos transistores de efecto campo selectivo a iones compara la concentración de determinados iones en una solución a medir con la concentración de determinados iones en una solución de referencia confinada en un microdepósito con un microcanal. Para ello el microdepósito y el microcanal cubren al menos la puerta de uno de los transistores de efecto campo selectivo a iones, e integran un conjunto parcialmente relleno de un material poroso que cubre la totalidad de dicha puerta y al menos la base del microcanal.Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de adición a la patent