An Approach to an Inhibition Electronic Tongue to Detect On-Line Organophosphorus Insecticides Using a Computer Controlled Multi-Commuted Flow System

An approach to an inhibition bioelectronic tongue is presented. The work is focused on development of an automated flow system to carry out experimental assays, a custom potentiostat to measure the response from an enzymatic biosensor, and an inhibition protocol which allows on-line detections. A Multi-commuted Flow Analysis system (MCFA) was selected and developed to carry out assays with an improved inhibition method to detect the insecticides chlorpyrifos oxon (CPO), chlorfenvinfos (CFV) and azinphos methyl-oxon (AZMO). The system manifold comprised a peristaltic pump, a set of seven electronic valves controlled by a personal computer electronic interface and software based on LabView® to control the sample dilutions into the cell. The inhibition method consists in the injection of the insecticide when the enzyme activity has reached the plateau of the current; with this method the incubation time is avoided. A potentiostat was developed to measure the response from the enzymatic biosensor. Low limits of detection of 10 nM for CPO, CFV, and AZMO were achieved

State-of-the-Art of (Bio)Chemical Sensor Developments in Analytical Spanish Groups

(Bio)chemical sensors are one of the most exciting fields in analytical chemistry today. The development of these analytical devices simplifies and miniaturizes the whole analytical process. Although the initial expectation of the massive incorporation of sensors in routine analytical work has been truncated to some extent, in many other cases analytical methods based on sensor technology have solved important analytical problems. Many research groups are working in this field world-wide, reporting interesting results so far. Modestly, Spanish researchers have contributed to these recent developments. In this review, we summarize the more representative achievements carried out for these groups. They cover a wide variety of sensors, including optical, electrochemical, piezoelectric or electro-mechanical devices, used for laboratory or field analyses. The capabilities to be used in different applied areas are also critically discussed

Luminescence Sensors Applied to Water Analysis of Organic Pollutants—An Update

The development of chemical sensors for environmental analysis based on fluorescence, phosphorescence and chemiluminescence signals continues to be a dynamic topic within the sensor field. This review covers the fundamentals of this type of sensors, and an update on recent works devoted to quantifying organic pollutants in environmental waters, focusing on advances since about 2005. Among the wide variety of these contaminants, special attention has been paid polycyclic aromatic hydrocarbons, pesticides, explosives and emerging organic pollutants. The potential of coupling optical sensors with multivariate calibration methods in order to improve the selectivity is also discussed

Development of a novel high resolution and high throughput biosensing technology based on a Monolithic High Fundamental Frequency Quartz Crystal Microbalance (MHFF-QCM). Validation in food control

Tesis por compendio[ES] La sociedad actual demanda un mayor control en la seguridad y calidad de los alimentos que se consumen. Esta preocupación se ve reflejada en los diferentes planes estatales y europeos de investigación científica, los cuales, plantean la necesidad de innovar y desarrollar nuevas técnicas analíticas que cubran los requerimientos actuales. En el presente documento se aborda el problema de la presencia de residuos químicos en la miel. El origen de los mismos se debe, fundamentalmente, a los tramientos veterinarios con los que se tratan enfermedades y parásitos en las abejas, y a los tratamientos agrícolas con los que las abejas se ponen en contacto cuando recolectan el néctar en cultivos próximos a las colmenas. La Agencia Europea de Seguridad Alimentaria (EFSA) confirma esta realidad al notificar numerosas alertas sanitarias en la miel. En los últimos años, los métodos de análisis basados en inmunosensores piezoeléctricos se han posicionado como la base de una técnica de cribado muy prometedora, la cual puede ser empleada como técnica complementaria a las clásicas de cromatografía, gracias a su sencillez, rapidez y bajo coste. La tecnología de resonadores High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) combina la detección directa en tiempo real, alta sensibilidad y selectividad con un fácil manejo y coste reducido en comparación con otras técnicas. Además, está tecnología permite aumentar el rendimiento del análisis mediante el diseño de arrays de resonadores en un mismo sustrato (Monolithic HFF-QCMD). En este documento se presenta el diseño de un array de 24 sensores HFF-QCMD, junto con un cartucho de micro-fluídica que traza diversos microcanales sobre los diferentes elementos sensores, a los que hace llegar la muestra de miel diluida a analizar. El cartucho actúa también como interfaz para realizar la conexión entre el array de resonadores y el instrumento de caracterización de los mismos. Para obtener el máximo partido del array diseñado, se desarrolla un método de medida robusto y fiable que permite elevar la tasa de adquisición de datos para facilitar la toma de registros eléctricos de un elevado número de resonadores de forma simultánea, e incluso en varios armónicos del modo fundamental de resonancia. La gran sensibilidad de la tecnología HFF-QCMD a los eventos bioquímicos a caracterizar se extiende también a otro tipo eventos externos, como son los cambios de temperatura o presión, lo que es necesario minimizar con el fin de reducir el impacto que estas perturbaciones no deseadas provocan en la estabilidad y fiabilidad de la medida. Con este fin, se desarrolla un algoritmo de procesado de señal basado en la Discrete Transform Wavelet (DTW). Finalmente, todos los desarrollos tecnológicos realizados se validan mediante la implementación de un inmunoensayo para la detección simultánea, en muestras de mieles reales, de residuos químicos de naturaleza química muy diferente, a saber, el fungicida tiabendazol y el antibiótico sulfatiazol.[CA] La societat actual demanda un major control en la seguretat i qualitat dels aliments que es consumeixen. Aquesta preocupació es veu reflectida en els diferents plans estatals i europeus d'investigació científica, els quals, plantegen la necessitat d'innovar i desenvolupar noves tècniques analítiques que cobrisquen els requeriments actuals. En el present document s'aborda el problema de la presència de residus químics en la mel. L'origen dels mateixos es deu, fonamentalment, als tractaments veterinaris amb els quals es tracten malalties i paràsits en les abelles, i als tractaments agrícoles amb els quals les abelles es posen en contacte quan recol·lecten el nèctar en cultius pròxims als ruscos. L'Agència Europea de Seguretat Alimentària (EFSA) confirma aquesta realitat notificant nombroses alertes sanitàries en la mel. En els últims anys, els mètodes d'anàlisis basades en immunosensors piezoelèctrics s'han posicionat com la base d'una tècnica de garbellat molt prometedora, la qual pot ser emprada com a tècnica complementària a les clàssiques de cromatografia, gràcies a la seua senzillesa, rapidesa i baix cost. La tecnologia de ressonadors High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) combina la detecció directa en temps real, alta sensibilitat i selectivitat amb un fàcil maneig i cost reduït en comparació amb altres tècniques. A més, està tecnologia permet augmentar el rendiment del anàlisi mitjançant el disseny d'arrays de ressonadors en un mateix substrat (Monolithic HFF-QCMD). En aquest document es presenta el disseny d'un array de 24 sensors HFF-QCMD, juntament amb un cartutx de microfluídica que estableix diversos microcanals sobre els diferents elements sensors, als quals fa arribar la mostra de mel diluïda a analitzar. El cartutx actua també com a interfície per a realitzar la connexió entre l'array de ressonadors i l'instrument de caracterització d'aquests. Per a traure el màxim partit a l'array dissenyat, es desenvolupa un mètode de mesura robust i fiable que permet elevar la taxa d'adquisició de dades per a facilitar la presa de registres elèctrics d'un elevat nombre de ressonadors de manera simultània, i fins i tot en diversos harmònics del mode fonamental de ressonància. La gran sensibilitat de la tecnologia HFF-QCMD als esdeveniments bioquímics a caracteritzar s'estén també a un altre tipus esdeveniments externs, com són els canvis de temperatura o pressió, la qual cosa és necessari minimitzar amb la finalitat de reduir l'impacte que aquestes pertorbacions no desitjades provoquen en l'estabilitat i fiabilitat de la mesura. A aquest efecte, es desenvolupa un algorisme de processament de senyal basat en la Discrete Transform Wavelet (DTW). Finalment, tots els desenvolupaments tecnològics realitzats es validen mitjançant la implementació d'un immunoassaig per a la detecció simultània, en mostres de mel reals, de residus químics de naturalesa química molt diferent, a saber, el fungicida tiabendazol i l'antibiòtic sulfatiazol.[EN] Currently, society demands greater control over the safety and quality of the food consumed. This concern is reflected in the different states and European plans for scientific research, which establish the necessity to innovate and develop new analytical techniques that meet current requirements. This document addresses the problem of the presence of chemical residues in honey. Its origin is fundamentally due to the veterinary treatments against diseases and parasites in bees, and also to the agricultural treatments with which the bees come into contact when they collect the nectar in crops close to the hives. The European Food Safety Agency (EFSA) confirms this reality by notifying numerous health alerts in honey. In recent years, analysis methods based on piezoelectric immunosensors have been positioned as the basis of a very promising screening technique, which can be used as a complementary technique to the classic chromatography, thanks to its simplicity, speed and low cost. High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) resonator technology combines direct real-time detection, high sensitivity and selectivity with easy handling and low cost compared to other techniques. In addition, this technology allows increasing the performance of the analysis through the design of resonator arrays on the same substrate (Monolithic HFF-QCMD). This document presents the design of an array of 24 HFF-QCMD sensors, together with a microfluidic cartridge that establish various microchannels on the different sensor elements, to provide them the diluted honey sample to be analyzed. The cartridge also acts as an interface to make the connection between the array of resonators and the characterization instrument. To get the most out of the designed array, a robust and reliable measurement method has been developed that allows increasing the data acquisition rate to facilitate electrical parameters readout from a high number of resonators simultaneously, and even in several harmonics of the fundamental resonance mode. The great sensitivity of the HFF-QCMD technology to the biochemical events to be characterized also is extended to other types of external events, such as changes in temperature or pressure, which must be minimized in order to reduce the impact that these unwanted disturbances cause in the stability and reliability of the measurement. To this end, a signal processing algorithm based on the Discrete Transform Wavelet (DTW) is developed. Finally, all the technological developments carried out are validated through the implementation of an immunoassay for the simultaneous detection, in real honey samples, of chemical residues of very different chemical nature, namely, the fungicide thiabendazole and the antibiotic sulfathiazole.The authors would also like to thank Jorge Martínez from the Laboratory of High Frequency Circuits (LCAF) of the Universitat Politècnica de València (UPV) for assistance with profilometry, and Manuel Planes, José Luis Moya, Mercedes Tabernero, Alicia Nuez and Joaquin Fayos from the Electron Microscopy Services of the UPV for helping with the AFM, and SEM measurements. M.Calero is the recipient of the doctoral fellowship BES-2017-080246 from the Spanish Ministry of Economy, Industry and Competitiveness (Madrid, Spain). This research was funded by Spanish Ministry of Economy and Competitiveness with FEDER funds (AGL 2016-77702-R) and European Commission Horizon 2020 Programme (Grant Agreement number H2020-FETOPEN-2016-2017/737212-CATCH-U-DNA - Capturing non-Amplified Tumor Circulating DNA with Ultrasound Hydrodynamics) for which the authors are grateful. Román Fernández is with the Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, València, Spain and with Advanced Wave Sensors S.L., Paterna, València, Spain. (e-mail: [email protected]); Yolanda Jiménez, Antonio Arnau and María Calero are with the Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, València, Spain; Ilya Reiviakine is with Advanced Wave Sensors S.L., Paterna, Valencia, Spain and with the Department of Bioengineering, University of Washington, Seattle, WA, 98150 USA; María Isabel Rocha-Gaso and José Vicente García are with Advanced Wave Sensors S.L., Paterna, València, Spain.Calero Alcarria, MDS. (2022). Development of a novel high resolution and high throughput biosensing technology based on a Monolithic High Fundamental Frequency Quartz Crystal Microbalance (MHFF-QCM). Validation in food control [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182652TESISCompendi

Recent advances in the fabrication and application of screen-printed electrochemical (bio)sensors based on carbon materials for biomedical, agri-food and environmental analyses

This review describes recent advances in the fabrication of electrochemical (bio)sensors based on screen-printing technology involving carbon materials and their application in biomedical, agri-food and environmental analyses. It will focus on the various strategies employed in the fabrication of screen-printed (bio)sensors, together with their performance characteristics; the application of these devices for the measurement of selected naturally occurring biomolecules, environmental pollutants and toxins will be discussed