Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.868
Filtrar
1.
Methods Mol Biol ; 2265: 265-276, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33704721

RESUMEN

Liquid biopsy has emerged as the next generation target for diagnostics and therapeutic monitoring of many diseases including cancer. Liquid biopsy offers noninvasive analysis of aberrant biomolecular changes (e.g., aberrant protein expression, DNA mutation) which can provide crucial information on disease stages and therapy responses. As a diagnostically important biomarker for melanoma, the detection of the BRAFV600E aberration at the DNA and protein level in liquid biopsies confers an attractive option. This method describes the preparation and operation of an integrated multimolecular sensor (IMMS) for simultaneous detection of the BRAFV600E aberration in both molecular forms from circulating melanoma cells in liquid biopsy. IMMS integrates specific melanoma cell capture, cell release, cell lysis, and electrochemical BRAFV600E detection on a single device. IMMS is demonstrated for a sample-to-answer workflow of plasma spiked with melanoma cells.


Asunto(s)
Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Dispositivos Laboratorio en un Chip , Melanoma/metabolismo , Microfluídica/instrumentación , Microfluídica/métodos , Proteínas Proto-Oncogénicas B-raf/metabolismo , Neoplasias Cutáneas/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Técnicas Biosensibles/instrumentación , Técnicas de Cultivo de Célula/métodos , Humanos , Inmunoensayo/instrumentación , Biopsia Líquida/métodos , Melanoma/genética , Melanoma/patología , Mutación , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patología , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología
2.
Front Immunol ; 12: 635677, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33777026

RESUMEN

The outbreak and worldwide pandemic of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have a significant impact on global economy and human health. In order to reduce the disease spread, 16 monoclonal antibodies (McAbs) again SARS-CoV-2 were generated by immunized mice with the spike protein receptor binding domain (RBD), which was expressed in Chinese hamster ovary cell (CHO). A colloidal gold-based immunochromatographic strip was developed with two McAbs to detect SARS-CoV-2 spike protein, which can play a potential role in monitoring vaccine quality. The strip is highly specific, detecting only SARS-CoV-2 spike protein, and does not show any non-specific reactions with syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and other coronavirus and influenza viruses. The strip detected subunit vaccine in our laboratory with a detection limit of spike protein of 62.5 ng/mL. This strip provides an effective method in monitoring vaccine quality by detecting the antigen content of spike protein.


Asunto(s)
Antígenos Virales/análisis , /diagnóstico , Oro Coloide , Inmunoensayo/instrumentación , Tiras Reactivas , Glicoproteína de la Espiga del Coronavirus/análisis , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Antígenos Virales/inmunología , /virología , Humanos , Límite de Detección , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Glicoproteína de la Espiga del Coronavirus/inmunología
3.
Biosensors (Basel) ; 11(3)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670852

RESUMEN

The diagnosis of respiratory viruses of zoonotic origin (RVsZO) such as influenza and coronaviruses in humans is crucial, because their spread and pandemic threat are the highest. Surface-enhanced Raman spectroscopy (SERS) is an analytical technique with promising impact for the point-of-care diagnosis of viruses. It has been applied to a variety of influenza A virus subtypes, such as the H1N1 and the novel coronavirus SARS-CoV-2. In this work, a review of the strategies used for the detection of RVsZO by SERS is presented. In addition, relevant information about the SERS technique, anthropozoonosis, and RVsZO is provided for a better understanding of the theme. The direct identification is based on trapping the viruses within the interstices of plasmonic nanoparticles and recording the SERS signal from gene fragments or membrane proteins. Quantitative mono- and multiplexed assays have been achieved following an indirect format through a SERS-based sandwich immunoassay. Based on this review, the development of multiplex assays that incorporate the detection of RVsZO together with their specific biomarkers and/or secondary disease biomarkers resulting from the infection progress would be desirable. These configurations could be used as a double confirmation or to evaluate the health condition of the patient.


Asunto(s)
/diagnóstico , Inmunoensayo/métodos , Virus de la Influenza A/aislamiento & purificación , Gripe Humana/diagnóstico , Espectrometría Raman/métodos , /instrumentación , Diseño de Equipo , Humanos , Inmunoensayo/instrumentación , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Espectrometría Raman/instrumentación
4.
Anal Chim Acta ; 1147: 30-37, 2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33485583

RESUMEN

Simple, low-cost, and sensitive new platforms for electrochemical immunosensors for virus detection have been attracted attention due to the recent pandemic caused by a new type of coronavirus (SARS-CoV-2). In the present work, we report for the first time the construction of an immunosensor using a commercial 3D conductive filament of carbon black and polylactic acid (PLA) to detect Hantavirus Araucaria nucleoprotein (Np) as a proof-of-concept. The recognition biomolecule was anchored directly at the filament surface by using N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride and N-Hydroxysuccinimide (EDC/NHS). Conductive and non-conductive composites of PLA were characterized using thermal gravimetric analysis (TGA), revealing around 30% w/w of carbon in the filament. Morphological features of composites were obtained from SEM and TEM measurements. FTIR measurement revealed that crosslinking agents were covalently bonded at the filament surface. Electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used for the evaluation of each step involved in the construction of the proposed immunosensor. The results showed the potentiality of the device for the quantitative detection of Hantavirus Araucaria nucleoprotein (Np) from 30 µg mL-1 to 240 µg mL-1 with a limit of detection of 22 µg mL-1. Also, the proposed immunosensor was applied with success for virus detection in 100x diluted human serum samples. Therefore, the PLA conductive filament with carbon black is a simple and excellent platform for immunosensing, which offers naturally carboxylic groups able to anchor covalently biomolecules.


Asunto(s)
Anticuerpos Antivirales/inmunología , Inmunoensayo/métodos , Proteínas de la Nucleocápside/inmunología , Impresión Tridimensional , Anticuerpos Inmovilizados/química , Anticuerpos Inmovilizados/inmunología , /virología , Espectroscopía Dieléctrica , Electrodos , Hantavirus/aislamiento & purificación , Hantavirus/metabolismo , Infecciones por Hantavirus/diagnóstico , Infecciones por Hantavirus/virología , Humanos , Inmunoensayo/instrumentación , Límite de Detección , Proteínas de la Nucleocápside/sangre , Hollín/química
5.
Food Chem ; 335: 127627, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32738534

RESUMEN

A colloidal gold immunochromatographic strip (ICS) for simultaneous detection of multiple transgenic proteins, including CP4 EPSPS, BT-Cry1Ab and BT-Cry1Ac, was developed in this study. The sensitivity of the strip to the target protein was 5 ng/mL for CP4 EPSPS, 100 ng/mL for BT-Cry1Ab and Cry1Ac, respectively. Parallel analysis for maize, soybean, sugar beet and cotton showed the strip could detect 1% of transgenic content in crops containing BT-Cry1Ab and Cry1Ac, and, at least, 0.1% of content in crops containing CP4 EPSPS. The detection results for seed samples indicated the multicomponent analysis ICS had good accuracy. The analysis could be completed within 10 min and had the advantages of being high-throughput, easy to operate and visual detection. This is the first report of semi-quantitative ICS for detecting three transgenic proteins simultaneously. The developed approach may provide insights into the development of ICS for analyzing simultaneously multiple components in genetically modified crops.


Asunto(s)
Proteínas Bacterianas/análisis , Productos Agrícolas/genética , Endotoxinas/análisis , Proteínas Hemolisinas/análisis , Inmunoensayo/instrumentación , Plantas Modificadas Genéticamente , Animales , Oro Coloide/química , Tiras Reactivas , Factores de Tiempo
6.
Food Chem ; 335: 127596, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32745840

RESUMEN

The ciprofloxacin (CIP) abuse has caused many problems threatening to human health. Here, we design the quantum dot microsphere (QDM) based immunochromatographic quantitative CIP test strip: when the sample under detection contains CIP, the QDM-monoclonal antibody (mAb) probes bound with the CIP and cannot be captured by CIP-bovine serum albumin (BSA) conjugation dispersed on the T lines, reducing the fluorescence intensities. These test strips can provide a low detection limit of 0.05 ng/mL and a wide linear detection range from 0.1 ng/mL to 100 ng/mL in high sensitivity and accuracy as well as good selectivity, reproducibility and stability. Moreover, a smartphone based test strip reader with the size of 85 mm × 48 mm × 44 mm is also fabricated using 3-D printing to automatically and quantitatively detect CIP. The whole process of CIP detection can be finished within 15 min, but only cost ~1 RMB (10 cents).


Asunto(s)
Antibacterianos/análisis , Ciprofloxacino/análisis , Inmunoensayo/instrumentación , Puntos Cuánticos/química , Animales , Anticuerpos Monoclonales/inmunología , Fluorescencia , Humanos , Límite de Detección , Microesferas , Impresión Tridimensional , Reproducibilidad de los Resultados , Albúmina Sérica Bovina/inmunología
7.
Food Chem ; 336: 127710, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32763739

RESUMEN

Conventional gold nanoparticle-based lateral flow immunoassay (LFIA) usually suffers a huge challenge in measuring target concentration in food matrices with dark color because of its poor resistance to the background matrix and color interference. To address this issue, we first report a novel bifunctional magneto-gold nanohybrid (MGNH) for the simultaneous magnetic separation and colorimetric target sensing by integrating MGNHs into LFIA. Under optimum conditions, an ultrasensitive detection of ochratoxin A (OTA) in grape juice was achieved with a limit of detection at 0.094 ng mL-1. The average recoveries of this MGNH-LFIA ranged from 92.31% to 108.97% with a coefficient of variation of below 12%. The excellent selectivity of our MGNH-LFIA against OTA was demonstrated. Besides, our MGNH-LFIA is comparable to liquid chromatography coupled with mass spectrometry in terms of accuracy, reproducibility, and practicability. The designed MGNH-LFIA platform is readily extended for improving other small molecule detection in food samples.


Asunto(s)
Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/análisis , Inmunoensayo/métodos , Nanopartículas del Metal/química , Ocratoxinas/análisis , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Oro/química , Inmunoensayo/instrumentación , Límite de Detección , Fenómenos Magnéticos , Ocratoxinas/inmunología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta , Vitis/química
8.
Methods Mol Biol ; 2237: 55-67, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33237408

RESUMEN

The coupling of surface plasmon resonance imaging (SPRi) with mass spectrometry (MS) offers a very promising multidimensional analysis. This system takes advantage of the two well-established techniques: SPR, which allows for the analysis of biomolecular interactions through the determination of kinetic and thermodynamic constants, and MS, which can characterize biological structures from mass measurements and fragmentation experiments. Here, a protocol for the coupling of SPRi with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is described using a biochip grafted by antibodies in an array format. Interaction between ß-lactoglobulin antibodies and the protein antigen is detected and analyzed by SPRi. Then, the arrayed biochip which fitted a commercially MALDI target was inserted in a MALDI source, and mass spectra were recorded directly from the biochip surface from each antibody spot, showing protein ions attributed to the corresponding specific protein antigens.


Asunto(s)
Antígenos/análisis , Espectrometría de Masas/métodos , Análisis por Matrices de Proteínas/métodos , Resonancia por Plasmón de Superficie/métodos , Antígenos/inmunología , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Dispositivos Laboratorio en un Chip , Espectrometría de Masas/instrumentación , Análisis por Matrices de Proteínas/instrumentación , Resonancia por Plasmón de Superficie/instrumentación
9.
Methods Mol Biol ; 2237: 69-82, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33237409

RESUMEN

Electrochemistry is a multidisciplinary field encompassing the study of analytes in solution for detection and quantification. For the medical field, this brings opportunities to the clinical practice of disease detection through measurements of disease biomarkers. Specifically, panels of biomarkers offer an important future option that can enable physicians' access to blood, saliva, or urine bioassays for screening diseases, as well as monitoring the progression and response to therapy. Here, we describe the simultaneous detection of eight protein cancer biomarkers in a 30-min assay by a microfluidic electrochemical immunoarray.


Asunto(s)
Biomarcadores de Tumor/análisis , Técnicas Electroquímicas/métodos , Pruebas Inmunológicas/métodos , Microfluídica/métodos , Análisis por Matrices de Proteínas/métodos , Técnicas Electroquímicas/instrumentación , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Pruebas Inmunológicas/instrumentación , Microfluídica/instrumentación , Análisis por Matrices de Proteínas/instrumentación
10.
J Agric Food Chem ; 69(1): 511-519, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33373219

RESUMEN

Gold nanoparticles (AuNPs) are the most commonly used signal materials in lateral flow immunoassay (LFIA). However, the assay sensitivity of traditional AuNP-based LFIA is usually limited by the incomplete competition between free target analytes and immobilized antigens for the binding of AuNP-labeled antibodies. To unfreeze this limitation, here, asymmetric Au-SiO2 Janus NPs (about 66 nm) were designed and synthesized. Au-SiO2 Janus NPs can assemble into snowman-like anisotropic structures and combine two different physicochemical properties at their opposite sides, where the AuNP side mainly possesses the antibody conjugating and signal providing functions and the SiO2 side primarily offers the stable function. In virtue of the unique asymmetric nanostructure, only the AuNP side can interact with target analytes by specific antigen-antibody interactions, which could significantly improve the efficiency of competition. Selecting furazolidone as a model analyte, the immunoassay biosensor showed a limit of detection as low as 0.08 ng/mL, 10-fold decreased than that of the AuNPs-LFIA. Moreover, the Au-SiO2 Janus NP lateral flow immunoassay was well applied in chicken, pork, honey, and beef food samples with visual detection limits of 0.8 ng/g, 0.16 ng/g, 0.4 ng/mL, and 0.16 ng/g, respectively. The Au-SiO2 Janus NPs possess the advantages of both materials, which will broaden their applications as a potential alternative in the rapid and sensitive detection of antibiotic residues.


Asunto(s)
Antibacterianos/análisis , Residuos de Medicamentos/análisis , Furazolidona/análisis , Inmunoensayo/métodos , Animales , Bovinos , Pollos , Contaminación de Alimentos/análisis , Oro/química , Miel/análisis , Inmunoensayo/instrumentación , Límite de Detección , Carne/análisis , Nanopartículas del Metal , Dióxido de Silicio/química , Porcinos
11.
J Sci Food Agric ; 101(2): 684-692, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32705699

RESUMEN

BACKGROUND: Sulfamethazine (SMZ), a veterinary drug widely used in animal husbandry, is harmful to human health when excess residues are present in food. In this study, a fast, reliable, and sensitive immunochromatographic assay (ICA) was developed on the basis of the competitive format by using time-resolved fluorescent nanobeads (TRFN) as label for the detection of SMZ in egg, honey, and pork samples. RESULTS: Under optimized working conditions, this method had limits of detection of 0.016, 0.049, and 0.029 ng mL-1 and corresponding linear ranges of 0.05 to 1.00, 0.05 to 5.00, and 0.05 to 1.00 ng mL-1 in egg, honey, and pork samples, respectively. The recovery experiments showed that the average recoveries ranged from 90.5% to 113.9%, 82.4% to 112.0%, and 79.8% to 93.4% with corresponding coefficients of variation of 4.1% to 11.7%, 7.5% to 11.5%, and 4.8% to 8.7% for egg, honey, and pork samples, respectively. The developed TRFN-ICA was also systematically compared with high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) by analyzing 45 actual samples from egg, honey, and pork. CONCLUSION: Overall, the developed TRFN-ICA had high reliability and excellent potential for the ultrasensitive detection of SMZ for food safety monitoring, also providing a universal platform for the on-site detection of other targets. © 2020 Society of Chemical Industry.


Asunto(s)
Antiinfecciosos/análisis , Huevos/análisis , Contaminación de Alimentos/análisis , Miel/análisis , Inmunoensayo/métodos , Carne/análisis , Sulfametazina/análisis , Drogas Veterinarias/análisis , Animales , Pollos , Inmunoensayo/instrumentación , Límite de Detección , Nanopartículas/análisis , Porcinos
12.
Anal Chem ; 93(3): 1826-1833, 2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33370087

RESUMEN

Collection of nasopharyngeal samples using swabs followed by the transfer of the virus into a solution and an RNA extraction step to perform reverse transcription polymerase chain reaction (PCR) is the primary method currently used for the diagnosis of COVID-19. However, the need for several reagents and steps and the high cost of PCR hinder its worldwide implementation to contain the outbreak. Here, we report a cotton-tipped electrochemical immunosensor for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus antigen. Unlike the reported approaches, we integrated the sample collection and detection tools into a single platform by coating screen-printed electrodes with absorbing cotton padding. The immunosensor was fabricated by immobilizing the virus nucleocapsid (N) protein on carbon nanofiber-modified screen-printed electrodes which were functionalized by diazonium electrografting. The detection of the virus antigen was achieved via swabbing followed by competitive assay using a fixed amount of N protein antibody in the solution. A square wave voltammetric technique was used for the detection. The limit of detection for our electrochemical biosensor was 0.8 pg/mL for SARS-CoV-2, indicating very good sensitivity for the sensor. The biosensor did not show significant cross-reactivity with other virus antigens such as influenza A and HCoV, indicating high selectivity of the method. Moreover, the biosensor was successfully applied for the detection of the virus antigen in spiked nasal samples showing excellent recovery percentages. Thus, our electrochemical immunosensor is a promising diagnostic tool for the direct rapid detection of the COVID-19 virus that requires no sample transfer or pretreatment.


Asunto(s)
/diagnóstico , Fibra de Algodón , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , /aislamiento & purificación , Anticuerpos Antivirales/inmunología , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Carbono/química , /inmunología , Técnicas Electroquímicas/instrumentación , Electrodos , Gossypium/química , Humanos , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/inmunología , Inmunoensayo/instrumentación , Límite de Detección , Nanofibras/química , Fosfoproteínas/química , Fosfoproteínas/inmunología , /inmunología
13.
Lab Chip ; 21(1): 93-104, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33319882

RESUMEN

The applications of serology tests to the virus SARS-CoV-2 are diverse, ranging from diagnosing COVID-19, understanding the humoral response to this disease, and estimating its prevalence in a population, to modeling the course of the pandemic. COVID-19 serology assays will significantly benefit from sensitive and reliable technologies that can process dozens of samples in parallel, thus reducing costs and time; however, they will also benefit from biosensors that can assess antibody reactivities to multiple SARS-CoV-2 antigens. Here, we report a high-throughput microfluidic device that can assess antibody reactivities against four SARS-CoV-2 antigens from up to 50 serum samples in parallel. This semi-automatic platform measures IgG and IgM levels against four SARS-CoV-2 proteins: the spike protein (S), the S1 subunit (S1), the receptor-binding domain (RBD), and the nucleocapsid (N). After assay optimization, we evaluated sera from infected individuals with COVID-19 and a cohort of archival samples from 2018. The assay achieved a sensitivity of 95% and a specificity of 91%. Nonetheless, both parameters increased to 100% when evaluating sera from individuals in the third week after symptom onset. To further assess our platform's utility, we monitored the antibody titers from 5 COVID-19 patients over a time course of several weeks. Our platform can aid in global efforts to control and understand COVID-19.


Asunto(s)
Anticuerpos Antivirales/sangre , Inmunoensayo/métodos , /inmunología , Área Bajo la Curva , /inmunología , Humanos , Inmunoensayo/instrumentación , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina M/sangre , Inmunoglobulina M/inmunología , Dispositivos Laboratorio en un Chip , Estudios Longitudinales , Fosfoproteínas/inmunología , Dominios Proteicos/inmunología , Curva ROC , Sensibilidad y Especificidad , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología
14.
Talanta ; 224: 121883, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33379092

RESUMEN

The COVID-19 pandemic has had a devastating impact worldwide and has brought clinical assays both for acute diagnosis and prior exposure determination to the forefront. Serological testing intended for point-of-care or laboratory use can be used to determine more accurate individual and population assessments of prior exposure to SARS-CoV-2; improve our understanding of the degree to which immunity is conveyed to subsequent exposures; and quantify immune response to future vaccines. In response to this pandemic, initially more than 90 companies deployed serology assays to the U.S. market, many of which made overstated claims for their accuracy, regulatory approval status, and utility for intended purpose. The U.S. Food and Drug Administration subsequently instituted an Emergency Use Authorization (EUA) procedure requiring that manufacturers submit validation data, but allowing newly developed serological tests to be marketed without the usual approval process during this crisis. Although this rapid deployment was intended to benefit public health, the incomplete understanding of immune response to the virus and lack of assay vetting resulted in quality issues with some of these tests, and thus many were withdrawn after submission. Common assay platforms include lateral flow assays which can serve an important niche of low cost, rapid turnaround, and increased accessibility whereas established laboratory-based platforms based on ELISAs and chemiluminescence expand existing technologies to SARS-CoV-2 and can provide throughput and quantification capabilities. While most of the currently EUA assays rely on these well-established platforms, despite their apparent technical simplicity, there are numerous practical challenges both for manufacturers in developing and for end-users in running and interpreting such assays. Within are discussed technical challenges to serology development for SARS-CoV-2, with an emphasis on lateral flow assay technology.


Asunto(s)
Anticuerpos Antivirales/análisis , /diagnóstico , Anticuerpos Antivirales/inmunología , /instrumentación , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Límite de Detección , Pandemias , /inmunología
15.
Biosens Bioelectron ; 171: 112715, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33099241

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a newly emerging human infectious disease. Because no specific antiviral drugs or vaccines are available to treat COVID-19, early diagnostics, isolation, and prevention are crucial for containing the outbreak. Molecular diagnostics using reverse transcription polymerase chain reaction (RT-PCR) are the current gold standard for detection. However, viral RNAs are much less stable during transport and storage than proteins such as antigens and antibodies. Consequently, false-negative RT-PCR results can occur due to inadequate collection of clinical specimens or poor handling of a specimen during testing. Although antigen immunoassays are stable diagnostics for detection of past infection, infection progress, and transmission dynamics, no matched antibody pair for immunoassay of SARS-CoV-2 antigens has yet been reported. In this study, we designed and developed a novel rapid detection method for SARS-CoV-2 spike 1 (S1) protein using the SARS-CoV-2 receptor ACE2, which can form matched pairs with commercially available antibodies. ACE2 and S1-mAb were paired with each other for capture and detection in a lateral flow immunoassay (LFIA) that did not cross-react with SARS-CoV Spike 1 or MERS-CoV Spike 1 protein. The SARS-CoV-2 S1 (<5 ng of recombinant proteins/reaction) was detected by the ACE2-based LFIA. The limit of detection of our ACE2-LFIA was 1.86 × 105 copies/mL in the clinical specimen of COVID-19 Patients without no cross-reactivity for nasal swabs from healthy subjects. This is the first study to detect SARS-CoV-2 S1 antigen using an LFIA with matched pair consisting of ACE2 and antibody. Our findings will be helpful to detect the S1 antigen of SARS-CoV-2 from COVID-19 patients.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Peptidil-Dipeptidasa A/química , Neumonía Viral/diagnóstico , Glicoproteína de la Espiga del Coronavirus/análisis , Anticuerpos Monoclonales/química , Técnicas Biosensibles/economía , Técnicas de Laboratorio Clínico/economía , Técnicas de Laboratorio Clínico/instrumentación , Infecciones por Coronavirus/economía , Diseño de Equipo , Humanos , Inmunoensayo/economía , Inmunoensayo/instrumentación , Inmunoconjugados/química , Pandemias , Sensibilidad y Especificidad , Factores de Tiempo
16.
Food Chem ; 338: 127820, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32827899

RESUMEN

Lactoferrin (LF), a bioactive multifunctional protein of the transferrin family, is found mainly in the secretions of all mammals, especially in milk. In the present study, a hybridoma cell (LF8) secreting IgG against bovine LF was screened, and the purified LF8 mAb showed high specificity and affinity to bovine LF. The linear range of ic-ELISA to detect LF was 9.76 ~ 625 ng/mL, with a limit of detection (LOD) of 0.01 ng/mL. The average recovery of intra- and inter-assay were (104.45 ± 4.12)% and (107.13 ± 4.72)%, respectively. The LOD of colloidal gold- and AuNFs-based strip by naked eye were 9.7 and 2.4 ng/mL, respectively, and the detection time was less than 10 min without any samples pretreatment and expensive equipment. The developed ELISA and lateral flow immunosensors based on specific IgG could be used directly for rapid detection of the bovine LF content in cow milk samples.


Asunto(s)
Inmunoensayo/métodos , Lactoferrina/análisis , Leche/química , Animales , Anticuerpos Monoclonales , Bovinos , Ensayo de Inmunoadsorción Enzimática , Femenino , Oro Coloide , Inmunoensayo/instrumentación , Inmunoglobulina G/inmunología , Lactoferrina/inmunología , Límite de Detección , Nanopartículas del Metal/química , Ratones Endogámicos BALB C , Sensibilidad y Especificidad
17.
Biosens Bioelectron ; 171: 112686, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33086175

RESUMEN

The diffusion of novel SARS-CoV-2 coronavirus over the world generated COVID-19 pandemic event as reported by World Health Organization on March 2020. The huge issue is the high infectivity and the absence of vaccine and customised drugs allowing for hard management of this outbreak, thus a rapid and on site analysis is a need to contain the spread of COVID-19. Herein, we developed an electrochemical immunoassay for rapid and smart detection of SARS-CoV-2 coronavirus in saliva. The electrochemical assay was conceived for Spike (S) protein or Nucleocapsid (N) protein detection using magnetic beads as support of immunological chain and secondary antibody with alkaline phosphatase as immunological label. The enzymatic by-product 1-naphtol was detected using screen-printed electrodes modified with carbon black nanomaterial. The analytical features of the electrochemical immunoassay were evaluated using the standard solution of S and N protein in buffer solution and untreated saliva with a detection limit equal to 19 ng/mL and 8 ng/mL in untreated saliva, respectively for S and N protein. Its effectiveness was assessed using cultured virus in biosafety level 3 and in saliva clinical samples comparing the data using the nasopharyngeal swab specimens tested with Real-Time PCR. The agreement of the data, the low detection limit achieved, the rapid analysis (30 min), the miniaturization, and portability of the instrument combined with the easiness to use and no-invasive sampling, confer to this analytical tool high potentiality for market entry as the first highly sensitive electrochemical immunoassay for SARS-CoV-2 detection in untreated saliva.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Saliva/virología , Técnicas Electroquímicas/instrumentación , Electrodos , Diseño de Equipo , Humanos , Inmunoensayo/instrumentación , Imanes/química , Proteínas de la Nucleocápside/análisis , Pandemias , Fosfoproteínas , Sensibilidad y Especificidad , Hollín/química , Glicoproteína de la Espiga del Coronavirus/análisis
18.
Biosens Bioelectron ; 169: 112604, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32980805

RESUMEN

Virus severely endangers human life and health, and the detection of viruses is essential for the prevention and treatment of associated diseases. Metal-organic framework (MOF), a novel hybrid porous material which is bridged by the metal clusters and organic linkers, has become a promising biosensor platform for virus detection due to its outstanding properties including high surface area, adjustable pore size, easy modification, etc. However, the MOF-based sensing platforms for virus detection are rarely summarized. This review systematically divided the detection platforms into nucleic acid and immunological (antigen and antibody) detection, and the underlying sensing mechanisms were interpreted. The nucleic acid sensing was discussed based on the properties of MOF (such as metal ion, functional group, geometry structure, size, porosity, stability, etc.), revealing the relationship between the sensing performance and properties of MOF. Moreover, antibodies sensing based on the fluorescence detection and antigens sensing based on molecular imprinting or electrochemical immunoassay were highlighted. Furthermore, the remaining challenges and future development of MOF for virus detection were further discussed and proposed. This review will provide valuable references for the construction of sophisticated sensing platform for the detection of viruses, especially the 2019 coronavirus.


Asunto(s)
Técnicas Biosensibles/métodos , Estructuras Metalorgánicas/química , Virosis/virología , Virus/aislamiento & purificación , Animales , Anticuerpos Antivirales/análisis , Antígenos Virales/análisis , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Modelos Moleculares , Impresión Molecular/instrumentación , Impresión Molecular/métodos , Ácidos Nucleicos/análisis , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/métodos , Virosis/diagnóstico
19.
Biosens Bioelectron ; 165: 112361, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729494

RESUMEN

The recent outbreak of the coronavirus disease (COVID-19) has left the world clueless. As the WHO declares this new contagion as a pandemic on the 11th of March 2020, the alarming rate of the spawn of the disease in such a short period has disarranged the globe. Standing against this situation researchers are strenuously searching for the key traits responsible for this pandemic. As knowledge regarding the dynamics and host-path interaction of COVID-19 causing Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is currently unknown, the formulation of strategies concerning antiviral treatment, vaccination, and epidemiological control stands crucial. Before designing adequate therapeutic strategies, it is extremely essential to diagnose the disease at the outset as early detection can have a greater impact on building health system capacity. Hence, a comprehensive review of strategies for COVID-19 diagnosis is essential in this existing global situation. In this review, sequentially, we have provided the clinical details along with genetic and proteomic biomarkers related to COVID-19. The article systematically enlightens a clear overview of the clinically adopted techniques for the detection of COVID-19 including oligonucleotide-based molecular detection, Point-of-Care immunodiagnostics, radiographical analysis/sensing system, and newly developed biosensing prototypes having commercial viability. The commercial kits/analytical methods based-sensing strategies have also been tabulated categorically. The critical insights on the developer, commercial brand name, detection methods, technical operational details, detection time, clinical specimen, status, the limit of detection/detection ability have been discussed comprehensively. We believe that this review may provide scientists, clinicians and healthcare manufacturers valuable information regarding the most recent developments/approaches towards COVID-19 diagnosis.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/métodos , Infecciones por Coronavirus/diagnóstico , Dispositivos Laboratorio en un Chip , Neumonía Viral/diagnóstico , Pruebas en el Punto de Atención , Animales , Anticuerpos Inmovilizados/química , Betacoronavirus/genética , Biomarcadores/análisis , Técnicas Biosensibles/instrumentación , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/virología , Diseño de Equipo , Humanos , Inmunoensayo/instrumentación , Inmunoensayo/métodos , Nanoestructuras/química , Pandemias , Neumonía Viral/sangre , Neumonía Viral/virología , Intensificación de Imagen Radiográfica/instrumentación , Intensificación de Imagen Radiográfica/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/instrumentación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
20.
Biosens Bioelectron ; 165: 112454, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729549

RESUMEN

The rapidly spreading outbreak of COVID-19 disease is caused by the SARS-CoV-2 virus, first reported in December 2019 in Wuhan, China. As of June 17, 2020, this virus has infected over 8.2 million people but ranges in symptom severity, making it difficult to assess its overall infection rate. There is a need for rapid and accurate diagnostics to better monitor and prevent the spread of COVID-19. In this review, we present and evaluate two main types of diagnostics with FDA-EUA status for COVID-19: nucleic acid testing for detection of SARS-CoV-2 RNA, and serological assays for detection of SARS-CoV-2 specific IgG and IgM patient antibodies, along with the necessary sample preparation for accurate diagnoses. In particular, we cover and compare tests such as the CDC 2019-nCoV RT-PCR Diagnostic Panel, Cellex's qSARS-CoV-2 IgG/IgM Rapid Test, and point-of-care tests such as Abbott's ID NOW COVID-19 Test. Antibody testing is especially important in understanding the prevalence of the virus in the community and to identify those who have gained immunity. We conclude by highlighting the future of COVID-19 diagnostics, which include the need for quantitative testing and the development of emerging biosensors as point-of-care tests.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Inmunoensayo/métodos , Neumonía Viral/diagnóstico , Pruebas en el Punto de Atención , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Infecciones por Coronavirus/sangre , Humanos , Inmunoensayo/instrumentación , Inmunoglobulina G/análisis , Inmunoglobulina G/sangre , Inmunoglobulina M/análisis , Inmunoglobulina M/sangre , Pandemias , Neumonía Viral/sangre , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/instrumentación , Manejo de Especímenes/instrumentación , Manejo de Especímenes/métodos , Estados Unidos , United States Food and Drug Administration
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...