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1.
Molecules ; 27(9)2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35566351

RESUMEN

Thyroid autoimmunity in Graves' disease (GD) is accompanied by Graves' orbitopathy (GO) in 40% of the cases. Orbital fibroblasts (OF) play a key role in the pathogenesis and cigarette smoking is a known deteriorating factor. Alongside conventional cigarettes (CC) new alternatives became available for smokers, including heated tobacco products (HTP) and E-cigarettes (ECIG). We aimed to study the cellular effects of smoke extracts (SE) in orbital fibroblasts. Primary OF cultures from GO and NON-GO orbits were exposed to different concentrations of SE (1%, 50%) and the changes were followed using Real Time Cell Electronic Sensing (RT-CES). Untreated GO and NON-GO cells had different maximum cell index (CI) values of 3.3 and 2.79 respectively (p < 0.0001). CC, HTP and ECIG treated NON-GO fibroblasts exhibited peak CIs of 2.62, 3.32 and 3.41 while treated GO cells' CIs were higher, 5.38, 6.25 and 6.33, respectively (p < 0.0001). The metabolic activity (MTT) decreased (p < 0.001) and hyaluronan production doubled (p < 0.02) after 50% of CC SE treatment in all cell cultures. GO fibroblasts were more sensitive to low concentration SE then NON-GO fibroblasts (p < 0.0001). The studied SEs exerted different effects. RT-CES is a sensitive technique to detect the effects of very low concentration of SE on fibroblasts.


Asunto(s)
Fumar Cigarrillos , Cigarrillo Electrónico a Vapor , Sistemas Electrónicos de Liberación de Nicotina , Oftalmopatía de Graves , Productos de Tabaco , Células Cultivadas , Fumar Cigarrillos/efectos adversos , Electrónica , Fibroblastos , Oftalmopatía de Graves/complicaciones , Oftalmopatía de Graves/metabolismo , Oftalmopatía de Graves/patología , Humanos
2.
J Food Sci Technol ; 57(1): 364-374, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31975739

RESUMEN

Grapefruit and lemon were exposed to phytosanitary irradiation doses of 0, 0.4, and 1 kGy, and then electronic-sensing screening of irradiation status and identification of radiation-induced ESR markers were conducted during 20 days storage. Codex standard photostimulated luminescence measurement (PSL1) was not a reliable indicator of irradiation status. Electronic tongue and electronic nose, however, showed potential as screening tools for discriminating irradiated fruits from non-irradiated counterparts based on principal component analysis of taste attributes and flavor patterns. Calibrated PSL approach clearly distinguished irradiated from non-irradiated samples based on the PSL ratio (PSL2/PSL1). Verification of irradiation status by electron spin resonance spectroscopy revealed clear paramagnetic centers from both irradiated fruits samples and ethanol-vacuum drying pretreatment improved radiation-induced ESR signal detection; not prominent enough in 0.4 kGy-irradiated commodities during 20 days of storage. Peel parts of both fruits showed high limonene which proportionally increased with irradiation doses (p < 0.05 kGy).

3.
Crit Rev Food Sci Nutr ; 57(13): 2896-2908, 2017 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26464111

RESUMEN

Since their development in 1943, artificial neural networks were extended into applications in many fields. Last twenty years have brought their introduction into winery, where they were applied following four basic purposes: authenticity assurance systems, electronic sensory devices, production optimization methods, and artificial vision in image treatment tools, with successful and promising results. This work reviews the most significant approaches for neural networks in winemaking technologies with the aim of producing a clear and useful review document.


Asunto(s)
Tecnología de Alimentos/métodos , Redes Neurales de la Computación , Vino , Humanos
4.
Molecules ; 22(11)2017 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-29113139

RESUMEN

Ocimum plants are traditionally used to manage HIV/AIDS in various African countries. The effects of Ocimum labiatum extract on HIV-1 protease (PR) and reverse transcriptase (RT) is presented here along with characterization of an identified bioactive compound, achieved through ¹H- and 13C-NMR. The extract's effect on HIV-1 replication was assessed by HIV-1 p24 antigen capture. Cytotoxicity of samples was evaluated using tetrazolium dyes and real-time cell electronic sensing (RT-CES). Ocimum labiatum inhibited HIV-1 PR with an IC50 value of 49.8 ± 0.4 µg/mL and presented weak inhibition (21%) against HIV-1 RT. The extract also reduced HIV-1 replication in U1 cells at a non-cytotoxic concentration (25 µg/mL). The CC50 value of the extract in U1 cells was 42.0 ± 0.13 µg/mL. The HIV-1 PR inhibiting fraction was purified using prep-HPLC and yielded a chlorophyll derivative, pheophytin-a (phy-a). Phy-a inhibited HIV-1 PR with an IC50 value of 44.4 ± 1.5 µg/mL (51 ± 1.7 µM). The low cytotoxicity of phy-a in TZM-bl cells was detected by RT-CES and the CC50 value in U1 cells was 51.3 ± 1.0 µg/mL (58.9 ± 1.2 µM). This study provides the first in vitro evidence of anti-HIV activity of O. labiatum and isolated phy-a, supporting further investigation of O. labiatum for lead compounds against HIV-1.


Asunto(s)
Fármacos Anti-VIH/farmacología , VIH-1/fisiología , Ocimum/química , Feofitinas/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Viral de la Expresión Génica/efectos de los fármacos , Proteasa del VIH/genética , Inhibidores de la Proteasa del VIH , Transcriptasa Inversa del VIH/genética , VIH-1/efectos de los fármacos , VIH-1/enzimología , VIH-1/genética , Estructura Molecular , Feofitinas/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Espectroscopía de Protones por Resonancia Magnética , Inhibidores de la Transcriptasa Inversa , Replicación Viral/efectos de los fármacos
5.
Food Chem ; 439: 138035, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039614

RESUMEN

Ceratocystis paradoxa is a major cause of postharvest disease in tender coconuts worldwide. We conducted a comprehensive study using widely targeted metabolomics, electronic tongue (E-tongue), and electronic nose (E-nose) analyses to investigate the impacts of C. paradoxa invasion on the quality of tender coconut water (TCW) from fresh control (FC), uninoculated (UN), skin-inoculated (SI), and deep-inoculated (DI) nuts. DI exhibited significantly higher taste indicators associated with bitterness, saltiness, astringency aftertaste, and bitter aftertaste, as well as odor sensor values related to various compounds such as long-chain alkanes, hydrides, methane, organic sulfides, etc. Invasion of C. paradoxa into the endosperm altered the flavor characteristics of TCW mainly through the modulation of carbohydrate and secondary metabolite pathways. Furthermore, significant correlations were observed between the differentially expressed flavorful metabolites and the sensor indicators of the E-nose and E-tongue. These findings offer valuable insights into understanding the impact of C. paradoxa infection on coconuts.


Asunto(s)
Cocos , Nariz Electrónica , Odorantes , Gusto , Lengua
6.
Food Sci Nutr ; 12(5): 3391-3404, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38726416

RESUMEN

This study performed a comparative analysis of the sensory and microbial profiles of light-flavor Bijou (LFD) from Taiyuan (Shanxi Province) and Suizhou (Hubei Province) in China. The results of the electronic nose showed that the aromatic substances of the LFD from Taiyuan (TLFD) were significantly higher (p < .05), while alcohol and aldehyde substances were significantly lower (p < .05) compared with the LFD from Suizhou (SLFD). The average response values of sensors W1C (sensitive to aromatic hydrocarbons), W3C (sensitive to amine and aromatic components), W5C (sensitive to olefins, aromatics, and polar molecules), and W2S (sensitive to alcohol and aldehyde compounds) to TLFD were 0.26, 0.33, 0.34, and 7.72, whereas the response values to SLFD were 0.25, 0.32, 0.33, and 8.04, respectively. The electronic tongue results showed that the aftertaste A (bitter aftertaste) and aftertaste B (astringent aftertaste) of the TLFD were significantly higher (p < .05) and umami was significantly lower (p < .05) as compared to the SLFD. The relative intensities of the aftertaste A, aftertaste B, and umami indicators of TLFD were 0.10, -0.008, and -0.22, respectively, while those of SLFD were -0.23, -0.36, and 0.835, respectively. MiSeq high-throughput sequencing results showed that TLFD exhibited lower fungal richness and diversity compared to SLFD. The dominant bacterial genera were mainly Bacillus (58.12%), Kroppenstedtia (10.11%), and Weissella (6.26%), and the dominant fungal genera were Saccharomycopsis (67.53%), Rasamsonia (9.90%), and Thermoascus (7.10%). Streptomyces and Staphylococcus were identified as the key characteristic microorganisms in TLFD, while Kroppenstedtia, Rasamsonia, and Thermoascus were the key characteristic microorganisms in SLFD. Correlation analysis indicated a stronger correlation between microorganisms and sensory characteristics in SLFD samples. This study provides valuable insights into the sensory and microbiological characteristics of LFD from different regions and offers a new perspective for understanding the production of differently flavored light-flavor Baijiu.

7.
Food Res Int ; 190: 114553, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945595

RESUMEN

Consumer preferences for walnut products are largely determined by the flavors released during mastication. In this study, a peeled walnut kernel (PWK) model was established with oral parameters decoupled using a Hutchings 3D model. The model explored in vitro variations using head-space solid-phase microextraction-gas chromatography-mass spectrometry and intelligent sensory techniques. The fracture strength, hardness, particle size, adhesiveness, springiness, gumminess, and chewiness were significantly reduced during mastication. We identified 61 volatile compounds and found that 2,5-dimethyl-3-ethylpyrazine is a key component, releasing predominantly baking and milky notes. Glutamic acid, alanine, arginine, and sucrose were identified as the key compounds in taste perception. The method can help establish a mastication model for nuts and facilitate breakthroughs in the development of walnut products and processing methods.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Juglans , Masticación , Nueces , Gusto , Compuestos Orgánicos Volátiles , Juglans/química , Nueces/química , Compuestos Orgánicos Volátiles/análisis , Humanos , Microextracción en Fase Sólida , Dureza , Tamaño de la Partícula , Aromatizantes/análisis
8.
Clin Exp Immunol ; 174(3): 433-40, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23815467

RESUMEN

Endothelial cell (EC) apoptosis seems to play an important role in the pathophysiology of pulmonary arterial hypertension (PAH). We aimed to test the hypothesis that circulating anti-endothelial cell antibodies (AECA) of PAH patients induce EC apoptosis. Immunoglobulin (Ig)G was purified from sera of PAH patients (n = 26), patients with systemic lupus erythematosus (SLE) nephritis without PAH (n = 16), patients with systemic sclerosis (SSc) without PAH (n = 58) and healthy controls (n = 14). Human umbilical vein endothelial cells (HUVECs) were incubated with patient or healthy control IgG for 24 h. Thereafter, apoptosis was quantified by annexin A5 binding and hypoploid cell enumeration by flow cytometry. Furthermore, real-time cell electronic sensing (RT-CES™) technology was used to monitor the effects of purified IgG from patient and healthy control IgG on HUVECs. As demonstrated previously, IgG of AECA-positive SLE nephritis patients (n = 7) induced a higher percentage of apoptosis of HUVECs compared to IgG of AECA-negative SLE nephritis patients and healthy controls. Furthermore, IgG of AECA-positive SLE nephritis patients induced a marked decrease in cell index as assessed by RT-CES™ technology. IgG of AECA-positive PAH patients (n = 12) and SSc patients (n = 13) did not alter the percentage of HUVEC apoptosis or cell index compared to IgG of AECA-negative PAH and SSc patients and healthy controls. AECA-positive PAH patients, in contrast to SLE nephritis patients, do not have circulating IgG AECA that enhances apoptosis of HUVECs in vitro. Further studies should focus on other mechanisms by which AECA may enhance EC apoptosis in PAH, such as antibody-dependent cell-mediated cytotoxicity.


Asunto(s)
Apoptosis/inmunología , Autoanticuerpos/inmunología , Células Endoteliales/metabolismo , Hipertensión Pulmonar/metabolismo , Inmunoglobulina G/inmunología , Adolescente , Adulto , Anciano , Autoanticuerpos/sangre , Células Endoteliales/inmunología , Hipertensión Pulmonar Primaria Familiar , Femenino , Humanos , Hipertensión Pulmonar/inmunología , Inmunoglobulina G/sangre , Nefritis Lúpica/sangre , Nefritis Lúpica/inmunología , Masculino , Persona de Mediana Edad , Esclerodermia Sistémica/sangre , Esclerodermia Sistémica/inmunología , Adulto Joven
9.
Food Chem ; 423: 136290, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37178596

RESUMEN

Currently, the effects of roasting methods on the flavor profile of peeled walnut kernels (PWKs) remain unknown. The effects of hot air binding (HAHA), radio frequency (HARF), and microwave irradiation (HAMW) on PWK were evaluated using olfactory, sensory, and textural techniques. Solvent Assisted Flavor Evaporation-Gas Chromatography-Olfactometry (SAFE-GC-O) identified 21 odor-active compounds with total concentrations of 229 µg/kg, 273 µg/kg and 499 µg/kg due to HAHA, HARF, and HAMW, respectively. HAMW exhibited the most prominent nutty taste, with the highest response among roasted milky sensors with the typical aroma of 2-ethyl-5-methylpyrazine. HARF had the highest values for chewiness (5.83 N·mm) and brittleness (0.68 mm); however, these attributes did not contribute to the flavor profile. The partial least squares regression (PLSR) model and VIP values showed 13 odor-active compounds were responsible for the sensory differences from different processes. The two-step treatment with HAMW improved the flavor quality of PWK.


Asunto(s)
Juglans , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas/métodos , Compuestos Orgánicos Volátiles/análisis , Aromatizantes/análisis , Olfato , Olfatometría/métodos , Odorantes/análisis
10.
Bioengineering (Basel) ; 9(11)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36354532

RESUMEN

Nano- or microdevices, enabling simultaneous, long-term, multisite, cellular recording and stimulation from many excitable cells, are expected to make a strategic turn in basic and applied cardiology (particularly tissue engineering) and neuroscience. We propose an innovative approach aiming to elicit bioelectrical information from the cell membrane using an integrated circuit (IC) bearing a coating of nanowires on the chip surface. Nanowires grow directly on the backend of the ICs, thus allowing on-site amplification of bioelectric signals with uniform and controlled morphology and growth of the NWs on templates. To implement this technology, we evaluated the biocompatibility of silicon and zinc oxide nanowires (NWs), used as a seeding substrate for cells in culture, on two different primary cell lines. Human cardiac stromal cells were used to evaluate the effects of ZnO NWs of different lengths on cell behavior, morphology and growth, while BV-2 microglial-like cells and GH4-C1 neuroendocrine-like cell lines were used to evaluate cell membrane-NW interaction and contact when cultured on Si NWs. As the optimization of the contact between integrated microelectronics circuits and cellular membranes represents a long-standing issue, our technological approach may lay the basis for a new era of devices exploiting the microelectronics' sensitivity and "smartness" to both improve investigation of biological systems and to develop suitable NW-based systems available for tissue engineering and regenerative medicine.

11.
Food Chem ; 394: 133487, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-35738150

RESUMEN

Currently, the effect of different pretreatments (i.e., radio frequency (RF), explosion puffing (EP), microwave (MW) and oven heating (OH)) on the flavor characteristics of peanut butter is unclear. Consequently, this study identified volatile aroma and non-volatile taste using HS-SPME/GC-MS combined with the use of an electronic nose, electronic tongue, and sniffing. 53 volatile compounds in four peanut butters were identified, MW-treated samples exhibited the most aroma-active compounds (43), followed by samples treated using OH (42), EP (38) and RF (21). Different pretreatment resulted in significant flavor differences in the aroma and taste. The peanut butter under MW pretreatment had a strongest nutty notes among the treatments. RF methods yielded smaller particle sizes and better texture compared to conventional OH. However, instantaneous heating using EP did not result in improvements to the aroma or taste. A combination of MW and RF may improve the flavor quality of peanut butter.


Asunto(s)
Microondas , Compuestos Orgánicos Volátiles , Arachis , Nariz Electrónica , Explosiones , Calefacción , Odorantes , Gusto
12.
J Drug Target ; 29(8): 822-833, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33641551

RESUMEN

Nanoscale robotics have the ability that it can productively transform multiple energy sources into motion and strength which reflects an expeditiously appearing and captivating area for research of robotics. In today's plethora, biomedical nanorobotics played an intricate character with numerous units of robots working at the pathological site in a coordinated manner. The synergistic action of the several nanorobotics has been employed for the fulfilment of the task such as large-scale detoxification, delivery of the large pharmacological/therapeutic efficacious payloads, etc. that is nearly unfeasible or unalterable practically by using single nanorobot. The collective intelligence of the nanorobot is advancing progressively at the nanoscale to reinforce their precision treatment potentially. Conclusively, after obtaining certain consideration regarding the nanorobotics sciences, many professionals are compendiously involving in the emerging highly efficacious therapeutic technology that encourages the scientist or designing of the tissues specific for the site-specific nanorobotic diagnostic devices. As a result, the closed and professional type between the field of Nanotechnology and Medical Sciences will provide another new highly oriented level to the domain of nanorobotics.


Asunto(s)
Sistemas de Liberación de Medicamentos/instrumentación , Nanotecnología/instrumentación , Robótica/instrumentación , Animales , Humanos
13.
Food Res Int ; 145: 110385, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34112388

RESUMEN

The flavor of salmonids is affected by species and origin. Sources of salmonid fish fillets are complex and difficult to identify and label fraud occasionally occurs in the market. In this study, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), electronic nose, electronic tongue and amino acid detection technologies were used to analyze flavor compounds in two salmonid species from different geographical origins. Fingerprints of volatile compounds of salmonid were constructed using HS-GC-IMS technology. Free amino acid (FAA) content differed in salmonids from different geographical origins. Regarding salmonid odor, HS-GC-IMS analysis results were basically consistent with those of the electronic nose. Regarding taste, the conclusions drawn from the electronic tongue were consistent with the amino acid test results. Therefore, our results demonstrate that flavor compounds can be used to distinguish salmonids from different geographical origins, providing a new dimension to food safety and authenticity. Furthermore, HS-GC-IMS, electronic nose and tongue can be used as tools in the market to identify food fraud.


Asunto(s)
Salmonidae , Compuestos Orgánicos Volátiles , Animales , Nariz Electrónica , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Movilidad Iónica , Gusto , Lengua , Compuestos Orgánicos Volátiles/análisis
14.
Anal Chim Acta ; 1184: 339028, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34625262

RESUMEN

Advanced stage detection of liver cirrhosis (LCi) would lead to high mortality rates in patients. Therefore, accurate and non-invasive tools for its early detection are highly needed using human emanations that may reflect this disease. Human breath, along with urine and blood, has long been one of the three main biological media for assessing human health and environmental exposure. The primary objective of this study was to explore the potential of using volatile organic compounds (VOCs) assay of exhaled breath and urine samples for the diagnosis of patients with LCi and healthy controls (HC). For this purpose, we used a hybrid electronic nose (E-nose) combining two sensor families, consisting of an array of five commercial chemical gas sensors and six interdigitated chemical gas sensors based on pristine or metal-doped WO3 nanowires for sensing volatile gases in exhaled breath. A voltammetric electronic tongue (VE-tongue), composed of five working electrodes, was dedicated to the analysis of urinary VOCs using cyclic voltammetry as a measurement technique. 54 patients were recruited for this study, comprising 22 patients with LCi, and 32 HC. The two-sensing systems coupled with pattern recognition methods, namely Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA), were trained to classify data clusters associated with the health status of the two groups. The diagnostic performances of the E-nose and VE-tongue systems were studied by using the receiver operating characteristic (ROC) method. The use of the E-nose or the VE-tongue separately, trained with these appropriate classifiers, showed a slight overlap indicating no clear discrimination between LCi patients and HC. To improve the performance of both electronic sensing devices, an emerging strategy, namely a multi-sensor data fusion technique, was proposed as a second aim to overcome this shortcoming. The data fusion approach of the two systems, at a medium level of abstraction, has demonstrated the ability to assess human health and disease status using non-invasive screening tools based on exhaled breath and urinary VOC analysis. This suggests that exhaled breath as well as urinary VOCs are specific to a disease state and could potentially be used as diagnostic methods.


Asunto(s)
Nariz Electrónica , Compuestos Orgánicos Volátiles , Pruebas Respiratorias , Estudios Transversales , Humanos , Cirrosis Hepática
15.
Toxicol In Vitro ; 73: 105124, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33636280

RESUMEN

The animal-based Draize test remains the gold standard for assessment of ocular irritation. However, subjective scoring methods, species differences, and animal welfare concerns have spurred development of alternative test methods. In this study, a novel in vitro method for assessing ocular irritancy was developed using a microelectric cell sensing technology, real-time cell analysis (RTCA). The cytotoxicity of sixteen compounds was assessed in two cell lines: ARPE-19 (human retina) and SIRC (rabbit cornea). In vitro inhibitory (IC50 and AUC50) values were determined at 6, 12, 24, 48, 72, and 96 h exposure, with a subset of values confirmed with MTT testing. The values displayed comparable predictivity of in vivo ocular irritation on the basis of a linear regression between the calculated values and each compounds' corresponding Draize-determined modified maximum average score (MMAS), but the ARPE-19 derived values were more strongly correlated than those from SIRC cells. Hence, IC50 values derived from ARPE-19 cells were used to predict the UN GHS/EU CLP classification of each test compound. The method was determined to have sensitivity of 90%, specificity of 50%, and overall concordance of 75%. Thus, RTCA testing may be best incorporated into a top-down tiered testing strategy for identification of ocular irritants in vitro.


Asunto(s)
Alternativas a las Pruebas en Animales , Ojo/efectos de los fármacos , Irritantes/toxicidad , Pruebas de Toxicidad/métodos , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Impedancia Eléctrica , Humanos , Irritantes/clasificación , Conejos
16.
ACS Biomater Sci Eng ; 6(7): 3811-3820, 2020 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-33463317

RESUMEN

The environmental monitoring of Ni is targeted at a threshold limit value of 0.34 µM, as set by the World Health Organization. This sensitivity target can usually only be met by time-consuming and expensive laboratory measurements. There is a need for inexpensive, field-applicable methods, even if they are only used for signaling the necessity of a more accurate laboratory investigation. In this work, bioengineered, protein-based sensing layers were developed for Ni detection in water. Two bacterial Ni-binding flagellin variants were fabricated using genetic engineering, and their applicability as Ni-sensitive biochip coatings was tested. Nanotubes of mutant flagellins were built by in vitro polymerization. A large surface density of the nanotubes on the sensor surface was achieved by covalent immobilization chemistry based on a dithiobis(succimidyl propionate) cross-linking method. The formation and density of the sensing layer was monitored and verified by spectroscopic ellipsometry and atomic force microscopy. Cyclic voltammetry (CV) measurements revealed a Ni sensitivity below 1 µM. It was also shown that, even after two months of storage, the used sensors can be regenerated and reused by rinsing in a 10 mM solution of ethylenediaminetetraacetic acid at room temperature.


Asunto(s)
Oro , Nanotubos , Ingeniería Biomédica , Microscopía de Fuerza Atómica , Agua
17.
Methods Enzymol ; 642: 403-433, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32828263

RESUMEN

There is an increasing interest for low cost, ultrasensitive, time saving yet reliable, point-of-care bioelectronic sensors. Electrolyte gated organic field effect transistors (EGOFETs) are proven compelling transducers for various sensing applications, offering direct electronic, label-free transduction of bio-recognition events along with miniaturization, fast data handling and processing. Given that field effect transistors act as intrinsically signal amplifiers, even a small change of a chemical or biological quantity may significantly alter the output electronic signal. In EGOFETs selectivity can be guaranteed by the immobilization of bioreceptors able to bind specifically a target analyte. The layer of receptors can be linked to one of the electronic active interfaces of the transistor, and the interactions with a target molecule affect the electronic properties of the device. The present chapter discusses main aspects of EGOFETs transducers along with detailed examples of how to tailor the device interfaces with desired functionality. The development of an "electronic tongue" based on an EGOFET device coupled to odorant binding proteins (OBPs) for enantiomers differentiation is presented.


Asunto(s)
Técnicas Biosensibles , Transistores Electrónicos , Electrólitos , Electrónica
18.
Artículo en Inglés | MEDLINE | ID: mdl-31441707

RESUMEN

The use of former food products (FFPs) as alternative feed ingredients in farm animal diets has several benefits. In fact, FFPs are a way of converting losses from the food industry into ingredients for the feed industry. FFPs are produced from packaged food and in general, they are recognised as safe. Packaging materials are not accepted as a feed ingredient according to Regulation (EC) No 767/2009, which imposes a rigorous evaluation of possible residues. A sensitive and objective detection method is therefore essential for an effective risk evaluation. Six FFP samples were subjected to electronic nose analysis. Each sample was assessed under three conditions: as-received, cleaned and experimentally-spiked. Packaging remnants were also quantified using a stereomicroscope. Data were analysed via principal component analysis using SPSS software. Although the stereomicroscopy analysis showed a low content of packaging remnants in as-received samples, the electronic nose was able to differentiate between cleaned, as-received and spiked samples. However, this method was not effective when different FFPs were analysed together. In the view of the limitations of this method, it can be concluded that the electronic nose can be considered an objective and sensitive method for the detection of packaging remnants in FFPs composed of the same matrix.


Asunto(s)
Alimentación Animal/análisis , Nariz Electrónica , Contaminación de Alimentos/análisis , Embalaje de Alimentos , Animales , Animales Domésticos
19.
Food Chem ; 286: 395-404, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30827624

RESUMEN

Rapid analytical methods for screening irradiated foods are required to comply with the approved standards for international trade. Dried shrimps irradiated at 1-7 kGy with gamma rays, electron beam (E-beam), and X-rays were screened with an electronic nose (E-nose) and electronic tongue (E-tongue). The data were compared with those from European standard methods (photostimulated luminescence, PSL) and direct epifluorescent filter technique/aerobic plate count, DEFT/APC). All irradiated shrimp samples were clearly discriminated from the non-irradiated control based on PSL photon count measurements and DEFT/APC microbial enumeration. The volatile patterns and taste attributes of the irradiated (>1 kGy from three sources) and control samples could be distinguished by the E-nose and E-tongue analyses through principal component analysis. Verification through electron spin resonance and thermoluminescence analyses validated screening results. The results indicate that E-sensing techniques showed potential for the rapid screening of irradiated foods like dried shrimps.


Asunto(s)
Análisis de los Alimentos/métodos , Irradiación de Alimentos , Mariscos/análisis , Espectroscopía de Resonancia por Spin del Electrón , Nariz Electrónica , Electrónica/instrumentación , Electrónica/métodos , Análisis de los Alimentos/instrumentación , Rayos gamma , Mediciones Luminiscentes/métodos , Rayos X
20.
J Pharm Biomed Anal ; 102: 64-77, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25244512

RESUMEN

Aroma profiles of ginseng samples at different ages were investigated using electronic nose (E-nose) and GC-MS techniques combined with chemometrics analysis. The bioactive ginsenoside and volatile oil content increased with age. E-nose performed well in the qualitative analyses. Both Principal Component Analysis (PCA) and Discriminant Functions Analysis (DFA) performed well when used to analyze ginseng samples, with the first two principal components (PCs) explaining 85.51% and the first two factors explaining 95.51% of the variations. Hierarchical Cluster Analysis (HCA) successfully clustered the different types of ginsengs into four groups. A total of 91 volatile constituents were identified. 50 of them were calculated and compared using GC-MS. The main fragrance ingredients were terpenes and alcohols, followed by aromatics and ester. The changes in terpenes, alcohols, aromatics, esters, and acids during the growth year once again confirmed the dominant role of terpenes. The Partial Least Squares (PLS) loading plot of gas sensors and aroma ingredients indicated that particular sensors were closely related to terpenes. The scores plot indicated that terpenes and its corresponding sensors contributed the most in grouping. As regards to quantitative analyze, 7 constituent of terpenes could be accurately explained and predicted by using gas sensors in PLS models. In predicting ginseng age using Back Propagation-Artificial Neural Networks (BP-ANN), E-nose data was found to predict more accurately than GC-MS data. E-nose measurement may be a potential method for determining ginseng age. The combination of GC-MS can help explain the hidden correlation between sensors and fragrance ingredients from two different viewpoints.


Asunto(s)
Nariz Electrónica , Ginsenósidos/análisis , Odorantes/análisis , Aceites Volátiles/análisis , Panax/química , Factores de Edad , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles/análisis
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