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1.
Mikrochim Acta ; 191(5): 294, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698253

RESUMEN

Early transition metal carbides (MXene) hybridized by precious metals open a door for innovative electrochemical biosensing device design. Herein, we present a facile one-pot synthesis of gold nanoparticles (AuNPs)-doped two-dimensional (2D) titanium carbide MXene nanoflakes (Ti3C2Tx/Au). Ti3C2Tx MXene exhibits high electrical conductivity and yields synergistic signal amplification in conjunction with AuNPs leading to excellent electrochemical performance. Thus Ti3C2Tx/Au hybrid nanostructure can be used as an electrode platform for the electrochemical analysis of various targets. We used screen-printed electrodes modified with the Ti3C2Tx/Au electrode and functionalized with different biorecognition elements to detect and quantify an antibiotic, ampicillin (AMP), and a mycotoxin, fumonisin B1 (FB1). The ultralow limits of detection of 2.284 pM and 1.617 pg.mL-1, which we achieved respectively for AMP and FB1 are far lower than their corresponding maximum residue limits of 2.8 nM in milk and 2 to 4 mg kg-1 in corn products for human consumption set by the United States Food and Drug Administration. Additionally, the linear range of detection and quantification of AMP and FB1 were, respectively, 10 pM to 500 nM and 10 pg mL-1 to 1 µg mL-1. The unique structure and excellent electrochemical performance of Ti3C2Tx/Au nanocomposite suggest that it is highly suitable for anchoring biorecognition entities such as antibodies and oligonucleotides for monitoring various deleterious contaminants in agri-food products.


Asunto(s)
Ampicilina , Técnicas Electroquímicas , Fumonisinas , Oro , Límite de Detección , Nanopartículas del Metal , Titanio , Fumonisinas/análisis , Oro/química , Ampicilina/análisis , Ampicilina/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Titanio/química , Técnicas Biosensibles/métodos , Leche/química , Antibacterianos/análisis , Electrodos , Contaminación de Alimentos/análisis , Animales
2.
Mikrochim Acta ; 191(5): 296, 2024 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702534

RESUMEN

A covalent organic framework-based strategy was designed for label-free colorimetric detection of pesticides. Covalent organic framework-based nanoenzyme with excellent oxidase-like catalytic activity was synthesized. Unlike other artificial enzymes, porphyrin-based covalent organic framework (p-COF) as the oxidase mimic showed highly catalytic chromogenic activity and good affinity toward TMB without the presence of H2O2, which can be used as substitute for peroxidase mimics and H2O2 system in the colorimetric reaction. Based on the fact that the pesticide-aptamer complex can inhibit the oxidase activity of p-COF and reduced the absorbance at 650 nm in UV-Vis spectrum, a label-free and facile colorimetric detection of pesticides was designed and fabricated. Under the optimized conditions, the COF-based colorimetric probe for pesticide detection displayed high sensitivity and selectivity. Taking fipronil for example the limit of detection was 2.7 ng/mL and the linear range was 5 -500,000 ng/mL. The strategy was successfully applied to the detection of pesticides with good recovery , which was in accordance with that of HPLC-MS/MS. The COF-based colorimetric detection was free of complicated modification H2O2, which guaranteed the accuracy and reliability of measurements. The COF-based sensing strategy is a potential candidate for the sensitive detection of pesticides of interests.


Asunto(s)
Colorimetría , Límite de Detección , Estructuras Metalorgánicas , Plaguicidas , Porfirinas , Colorimetría/métodos , Plaguicidas/análisis , Estructuras Metalorgánicas/química , Porfirinas/química , Peróxido de Hidrógeno/química , Oxidorreductasas/química , Aptámeros de Nucleótidos/química
3.
PLoS One ; 19(5): e0301234, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728290

RESUMEN

Nucleic Acid Lateral Flow Assays (NALFAs) are a promising solution for the point-of-care detection of viruses like SARS-CoV-2. However, they show some drawbacks, such as the great dependency on the use of antibodies and the need for post-amplification protocols that enable the preparation of amplicons for effective readings, as well as low sensitivity. Here, we developed amplicons of a specific SARS-CoV-2 gene tailed with single-strand DNA (ssDNA) sequences to hybridize with DNA probes immobilized on the NALFA strips, thus overcoming the aforementioned problems. Results have shown that tailed primers have not compromised the amplification efficiency and allowed the correct detection of the amplicons in the lateral flow strip. This approach has presented a limit of detection (LOD) of 25 RNA copies /reaction mix (1 copy/µL) and the test of cross-reactivity with other related viruses has not shown any cross-reactivity. Twenty clinical samples were evaluated by NALFA and simultaneously compared with the gold standard RT-qPCR protocol, originating equal results. Although the number of clinical specimens tested being relatively small, this indicates a sensitivity and specificity both of 100%. In short, an alternative NALFA was successfully implemented, rendering an accurate route for SARS-CoV-2 diagnosis, compatible with low-resource settings.


Asunto(s)
COVID-19 , ARN Viral , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Humanos , COVID-19/diagnóstico , COVID-19/virología , ARN Viral/genética , Límite de Detección , Técnicas de Amplificación de Ácido Nucleico/métodos , Sensibilidad y Especificidad , Prueba de Ácido Nucleico para COVID-19/métodos , ADN de Cadena Simple/genética , Cartilla de ADN/genética , Sondas de ADN
4.
Anal Chim Acta ; 1307: 342626, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719405

RESUMEN

BACKGROUND: C-reactive protein (CRP) represents an early clinical biomarker that indicates the presence of inflammatory or infectious conditions in the human body. Today's procedures approved by the Food and Drug Administration (FDA) imply expensive equipment and highly trained personnel to perform the test. Therefore, a new diagnostic method with high detection efficiency and less cost is urgently needed for delivering rapid and timely results in point-of-care (POC) service. RESULTS: Herein, we propose a new, equipment-free, and portable sensing method for the future POC detection of CRP based on the Tyndall effect (TE). In our study, aptamer-conjugated citrate-stabilized gold nanoparticles (apta-AuNPs) are exploited as the sensing platform. The apta-AuNPs' interaction with CRP in a saline environment leads to their aggregation, thus enhancing the scattering of light when the solution is exposed to a 640 nm pointer laser line. Firstly, the enhancement of the scattering light as a function of increasing concentration of CRP in solution is measured spectroscopically using a typical 90-degree angle spectrofluorometer and then the measurements are compared to the classic colorimetric detection using an UV-Vis spectrophotometer. Finally, to achieve high portability and accessibility, we demonstrate that the measurement of CRP concentration can be performed with similar accuracy but in a more direct and inexpensive way by using a laser pointer pen as the excitation source and a camera of a low-budget smartphone as a quantitative reader instead of most expensive spectrofluorometer. SIGNIFICANCE: The portable TE-based assay exhibits a wide linear dynamic range (1-60 µg/mL) for the detection of CRP with a limit of detection (LOD) of 92 ng/mL The proposed method is capable to integrate both standard and high-sensitivity CRP analysis in a single procedure with increased sensitivity and prompt delivery of analysis results. Moreover, the sensing procedure is significantly faster than the FDA approved ones with a detection time of only 10 min. Finally, as a proof-of-concept, our findings demonstrate excellent recovery for CRP detection in spiked and diluted urine samples, highlighting the strong potential of this sensing method for POC applications.


Asunto(s)
Aptámeros de Nucleótidos , Proteína C-Reactiva , Oro , Nanopartículas del Metal , Oro/química , Nanopartículas del Metal/química , Proteína C-Reactiva/análisis , Aptámeros de Nucleótidos/química , Humanos , Técnicas Biosensibles , Límite de Detección , Colorimetría , Sistemas de Atención de Punto
5.
J Mass Spectrom ; 59(6): e5031, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38726684

RESUMEN

Managing ocular microbial infections typically requires pharmacotherapy using antibiotic eye drops, such as moxifloxacin hydrochloride (MFX), combined with an antifungal agent like amphotericin B (AB). We carried out and validated an LC-MS/MS assay to quantify these compounds in rabbit tear fluid in order to look into the pharmacokinetics of these two drugs. We employed a protein precipitation technique for the extraction of drugs under examination. A Waters Symmetry C18 column was used to separate the analytes and internal standard. The composition of the mobile phase was like (A) 0.1% v/v formic acid in water and (B) methanol. The detection of MFX and AB was accomplished through the utilization of positive ion electrospray ionization under multiple reaction monitoring mode. The linearity curves for both analytes exhibited an acceptable trendline across a concentration range of 2.34-300 ng/mL for MFX and 7.81-1000 ng/mL for AB in surrogate rabbit tear fluid. The lower limit of quantitation for MFX was 2.34 ng/mL, while for AB, it was 7.81 ng/mL. The approach was strictly validated, encompassing tests of selectivity, linearity (with r2 > 0.99), precision, accuracy, matrix effects, and stability. Consequently, we employed this method to evaluate the pharmacokinetics profiles of MFX and AB in rabbit tear fluid following single topical doses.


Asunto(s)
Moxifloxacino , Espectrometría de Masas en Tándem , Lágrimas , Conejos , Animales , Espectrometría de Masas en Tándem/métodos , Lágrimas/química , Moxifloxacino/farmacocinética , Moxifloxacino/análisis , Reproducibilidad de los Resultados , Anfotericina B/farmacocinética , Anfotericina B/análisis , Límite de Detección , Antiinfecciosos/farmacocinética , Antiinfecciosos/análisis , Cromatografía Liquida/métodos , Soluciones Oftálmicas/farmacocinética , Modelos Lineales , Cromatografía Líquida con Espectrometría de Masas
6.
J Mass Spectrom ; 59(6): e5036, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38726689

RESUMEN

Turmeric and ginger are extensively employed as functional ingredients due to their high content of curcuminoids and gingerols, considered the key bioactive compounds found in these roots. In this study, we present an innovative and fast method for the assay of curcuminoids and gingerols in different foods containing the two spices, with the aim of monitoring the quality of products from a nutraceutical perspective. The proposed approach is based on paper spray tandem mass spectrometry coupled with the use of a labeled internal standard, which has permitted to achieve the best results in terms of specificity and accuracy. All the calculated analytical parameters were satisfactory; accuracy values are around 100% for all spiked samples and the precision data result lower than 15%. The protocol was applied to several real samples, and to demonstrate its robustness and reliability, the results were compared to those arising from the common liquid chromatographic method.


Asunto(s)
Curcuma , Alcoholes Grasos , Espectrometría de Masas en Tándem , Zingiber officinale , Zingiber officinale/química , Curcuma/química , Espectrometría de Masas en Tándem/métodos , Alcoholes Grasos/análisis , Reproducibilidad de los Resultados , Límite de Detección , Catecoles/análisis , Análisis de los Alimentos/métodos , Curcumina/análisis , Curcumina/análogos & derivados , Papel
7.
Luminescence ; 39(5): e4752, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38697778

RESUMEN

Prucalopride (PCD), is a modern medication approved by the United States in 2018 to alleviate constipation caused by motility issues. PCD demonstrates a strong affinity and selectivity toward the 5-HT4 receptor. The study here introduces a feasible, direct, non-extractive, and affordable pathway for PCD analytical tracking. The fluorimetric study is based on the on-off effect on the emission amplitude of fluorone-based dye (pyrosin B). In a one-pot experiment, the complex between PCD and pyrosin B is formed instantly in an acidic medium. Correlation between decreased pyrosin B emission and PCD concentrations provides a linear calibration plot from 50 to 900 ng/mL. PCD-dye complex system affecting variables were meticulously tuned. The values of the estimated limit of quantitation and limit of detection for the current methodology were 47.5 and 15.7 ng/mL, respectively. Conformity of the strategy validity was achieved by a comprehensive study of the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use criteria. The method was convincingly applied for PCD assay in tablets and content uniformity investigation. Furthermore, PCD tracking in the spiked biological fluid was applied. Finally, the method uses distilled water as dispersing medium which rise accommodation with the green chemistry principle.


Asunto(s)
Benzofuranos , Colorantes Fluorescentes , Benzofuranos/química , Benzofuranos/análisis , Colorantes Fluorescentes/química , Humanos , Espectrometría de Fluorescencia , Estructura Molecular , Límite de Detección
8.
Luminescence ; 39(5): e4775, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38745525

RESUMEN

A new smartphone-based chemiluminescence method has been introduced for the quantitative analysis of CL-20 (Hexanitroazaisowuertzitan) explosive. The solvent mixture, oxidizer agent, and concentration of the reactants were optimized using statistical procedures. CL-20 explosive showed a quenching effect on the chemiluminescence intensity of the luminol-NaClO reaction in the solvent mixture of DMSO/H2O. A smartphone was used as a detector to record the light intensity of chemiluminescence reaction as a video file. The recorded video file was converted to an analytical signal as intensity luminescence-time curve by a written code in MATLAB software. Dynamic range and limit of detection of the proposed method were obtained 2.0-240.0 and 1.1 mg⋅L-1, respectively, in optimized concentrations 1.5 × 10-3 mol⋅L-1 luminol and 1.0 × 10-2 mol⋅L-1 NaClO. Precursors TADB, HBIW, and TADNIW in CL-20 explosive synthesis did not show interference in measurement the CL-20 purity. The analysis of CL-20 spiked samples of soil and water indicated the satisfactory ability of the method in the analysis of real samples. The interaction of CL-20 molecules and OCl- ions is due to quench of chemiluminescence reaction of the luminol-NaClO.


Asunto(s)
Mediciones Luminiscentes , Luminol , Teléfono Inteligente , Mediciones Luminiscentes/métodos , Mediciones Luminiscentes/instrumentación , Luminol/química , Sustancias Explosivas/análisis , Luminiscencia , Límite de Detección
9.
Mikrochim Acta ; 191(6): 332, 2024 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748375

RESUMEN

Nifedipine (NIF), as one of the dihydropyridine calcium channel blockers, is widely used in the treatment of hypertension. However, misuse or ingestion of NIF can result in serious health issues such as myocardial infarction, arrhythmia, stroke, and even death. It is essential to design a reliable and sensitive detection method to monitor NIF. In this work, an innovative molecularly imprinted polymer dual-emission fluorescent sensor (CDs@PDA-MIPs) strategy was successfully designed for sensitive detection of NIF. The fluorescent intensity of the probe decreased with increasing NIF concentration, showing a satisfactory linear relationship within the range 1.0 × 10-6 M ~ 5.0 × 10-3 M. The LOD of NIF was 9.38 × 10-7 M (S/N = 3) in fluorescence detection. The application of the CDs@PDA-MIPs in actual samples such as urine and Qiangli Dingxuan tablets has been verified, with recovery ranging from 97.8 to 102.8% for NIF. Therefore, the fluorescent probe demonstrates great potential as a sensing system for detecting NIF.


Asunto(s)
Carbono , Dopamina , Colorantes Fluorescentes , Límite de Detección , Polímeros Impresos Molecularmente , Nifedipino , Puntos Cuánticos , Espectrometría de Fluorescencia , Puntos Cuánticos/química , Nifedipino/química , Nifedipino/análisis , Colorantes Fluorescentes/química , Polímeros Impresos Molecularmente/química , Dopamina/orina , Dopamina/análisis , Carbono/química , Espectrometría de Fluorescencia/métodos , Humanos , Polimerizacion , Impresión Molecular , Comprimidos/análisis
10.
Mikrochim Acta ; 191(6): 328, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743383

RESUMEN

The instant screening of patients with a tendency towards developing Alzheimer's disease (AD) is significant for providing preventive measures and treatment. However, the current imaging-based technology cannot meet the requirements in the early stage. Developing biosensor-based liquid biopsy technology could be overcoming this bottleneck problem. Herein, we developed a simple, low-cost, and sensitive electrochemical aptamer biosensor for detecting phosphorylated tau protein threonine 231 (P-tau231), the earliest and one of the most efficacious abnormally elevated biomarkers of AD. Gold nanoparticles (AuNPs) were electrochemically synthesized on a glassy carbon electrode as the transducer, exhibiting excellent conductivity, and were applied to amplify the electrochemical signal. A nucleic acid aptamer was designed as the receptor to capture the P-tau231 protein, specifically through the formation of an aptamer-antigen complex. The proposed biosensor showed excellent sensitivity in detecting P-tau 231, with a broad linear detection range from 10 to 107 pg/mL and a limit of detection (LOD) of 2.31 pg/mL. The recoveries of the biosensor in human serum ranged from 97.59 to 103.26%, demonstrating that the biosensor could be used in complex practical samples. In addition, the results showed that the developed biosensor has good repeatability, reproducibility, and stability, which provides a novel method for the early screening of AD.


Asunto(s)
Enfermedad de Alzheimer , Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Oro , Límite de Detección , Nanopartículas del Metal , Proteínas tau , Humanos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Aptámeros de Nucleótidos/química , Proteínas tau/sangre , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Oro/química , Nanopartículas del Metal/química , Fosforilación , Biomarcadores/sangre
11.
Mikrochim Acta ; 191(6): 331, 2024 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-38744722

RESUMEN

A broad host range phage-based nanozyme (Fe-MOF@SalmpYZU47) was prepared for colorimetric detection of multiple Salmonella enterica strains. The isolation of a broad host range phage (SalmpYZU47) capable of infecting multiple S. enterica strains was achieved. Then, it was directly immobilized onto the Fe-MOF to prepare Fe-MOF@SalmpYZU47, exhibiting peroxidase-like activity. The peroxidase-like activity can be specifically inhibited by multiple S. enterica strains, benefiting from the broad host range capture ability of Fe-MOF@SalmpYZU47. Based on it, a colorimetric detection approach was developed for S. enterica in the range from 1.0 × 102 to 1.0 × 108 CFU mL-1, achieving a low limit of detection (LOD) of 11 CFU mL-1. The Fe-MOF@SalmpYZU47 was utilized for detecting S. enterica in authentic food samples, achieving recoveries ranging from 91.88 to 105.34%. Hence, our proposed broad host range phage-based nanozyme exhibits significant potential for application in the colorimetric detection of pathogenic bacteria.


Asunto(s)
Colorimetría , Límite de Detección , Estructuras Metalorgánicas , Salmonella enterica , Colorimetría/métodos , Salmonella enterica/aislamiento & purificación , Salmonella enterica/química , Estructuras Metalorgánicas/química , Microbiología de Alimentos/métodos , Contaminación de Alimentos/análisis , Peroxidasa/química
12.
Mikrochim Acta ; 191(6): 330, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744738

RESUMEN

In view of a large number of people infected with Helicobacter pylori (H. pylori) with great harm followed, there is an urgent need to develop a non-invasive, easy-to-operate, and rapid detection method, and to identify effective sterilization strategies. In this study, highly specific nanoprobes with nanozyme activity, Ag@Pt nanoparticles (NPs) with the antibody, were utilized as a novel lateral flow immunoassay (LFIA). The optical label (Ag@Pt NPs) was enhanced by the introduction of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) and compared with a gold nanoparticles (Au NPs) optical label. Under the optimal condition, Ag@Pt-LFIA and TMB-enhanced Ag@Pt-LFIA for H. pylori were successfully established, two of which were over twofold and 100-fold more sensitive than conventional visual Au NP-based LFIA, respectively. Furthermore, Ag@Pt NPs with the antibody irradiated with NIR laser (808 nm) at a power intensity of 550 mW/cm2 for 5 min exhibited a remarkable antibacterial effect. The nanoprobes could close to bacteria through effective interactions between antibodies and bacteria, thereby benefiting photothermal sterilization. Overall, Ag@Pt NPs provide promising applications in pathogen detection and therapeutic applications.


Asunto(s)
Aleaciones , Helicobacter pylori , Nanopartículas del Metal , Platino (Metal) , Plata , Helicobacter pylori/efectos de la radiación , Helicobacter pylori/efectos de los fármacos , Plata/química , Nanopartículas del Metal/química , Platino (Metal)/química , Aleaciones/química , Antibacterianos/farmacología , Antibacterianos/química , Inmunoensayo/métodos , Bencidinas/química , Oro/química , Humanos , Esterilización/métodos , Límite de Detección
13.
J Agric Food Chem ; 72(19): 11241-11250, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709728

RESUMEN

The fungicide phenamacril has been employed to manage Fusarium and mycotoxins in crops, leading to persistent residues in the environment and plants. Detecting phenamacril is pivotal for ensuring environmental and food safety. In this study, haptens and artificial antigens were synthesized to produce antiphenamacril monoclonal antibodies (mAbs). Additionally, gold nanoparticles coated with a polydopamine shell were synthesized and conjugated with mAbs, inducing fluorescence quenching in quantum dots. Moreover, a dual-readout immunochromatographic assay that combines the positive signal from fluorescence with the negative signal from colorimetry was developed to enable sensitive and precise detection of phenamacril within 10 min, achieving detection limits of 5 ng/mL. The method's reliability was affirmed by using spiked wheat flour samples, achieving a limit of quantitation of 0.05 mg/kg. This analytical platform demonstrates high sensitivity, outstanding accuracy, and robust tolerance to matrix effects, making it suitable for the rapid, onsite, quantitative screening of phenamacril residues.


Asunto(s)
Colorimetría , Contaminación de Alimentos , Fungicidas Industriales , Residuos de Plaguicidas , Fungicidas Industriales/análisis , Contaminación de Alimentos/análisis , Colorimetría/métodos , Residuos de Plaguicidas/análisis , Anticuerpos Monoclonales/química , Cromatografía de Afinidad/métodos , Cromatografía de Afinidad/instrumentación , Fluorescencia , Triticum/química , Nanopartículas del Metal/química , Oro/química , Límite de Detección , Harina/análisis
14.
J Nanobiotechnology ; 22(1): 239, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38735951

RESUMEN

Widespread distribution of porcine epidemic diarrhea virus (PEDV) has led to catastrophic losses to the global pig farming industry. As a result, there is an urgent need for rapid, sensitive and accurate tests for PEDV to enable timely and effective interventions. In the present study, we develop and validate a floating gate carbon nanotubes field-effect transistor (FG CNT-FET)-based portable immunosensor for rapid identification of PEDV in a sensitive and accurate manner. To improve the affinity, a unique PEDV spike protein-specific monoclonal antibody is prepared by purification, and subsequently modified on FG CNT-FET sensor to recognize PEDV. The developed FET biosensor enables highly sensitive detection (LoD: 8.1 fg/mL and 100.14 TCID50/mL for recombinant spike proteins and PEDV, respectively), as well as satisfactory specificity. Notably, an integrated portable platform consisting of a pluggable FG CNT-FET chip and a portable device can discriminate PEDV positive from negative samples and even identify PEDV and porcine deltacoronavirus within 1 min with 100% accuracy. The portable sensing platform offers the capability to quickly, sensitively and accurately identify PEDV, which further points to a possibility of point of care (POC) applications of large-scale surveillance in pig breeding facilities.


Asunto(s)
Técnicas Biosensibles , Nanotubos de Carbono , Virus de la Diarrea Epidémica Porcina , Virus de la Diarrea Epidémica Porcina/aislamiento & purificación , Animales , Porcinos , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Nanotubos de Carbono/química , Límite de Detección , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Anticuerpos Monoclonales/inmunología , Transistores Electrónicos , Enfermedades de los Porcinos/diagnóstico , Enfermedades de los Porcinos/virología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/análisis , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , Anticuerpos Antivirales/inmunología , Diseño de Equipo
15.
Nat Commun ; 15(1): 4035, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740742

RESUMEN

Rapid and accurate detection of respiratory virus aerosols is highlighted for virus surveillance and infection control. Here, we report a wireless immunoassay technology for fast (within 10 min), on-site (wireless and battery-free), and sensitive (limit of detection down to fg/L) detection of virus antigens in aerosols. The wireless immunoassay leverages the immuno-responsive hydrogel-modulated radio frequency resonant sensor to capture and amplify the recognition of virus antigen, and flexible readout network to transduce the immuno bindings into electrical signals. The wireless immunoassay achieves simultaneous detection of respiratory viruses such as severe acute respiratory syndrome coronavirus 2, influenza A H1N1 virus, and respiratory syncytial virus for community infection surveillance. Direct detection of unpretreated clinical samples further demonstrates high accuracy for diagnosis of respiratory virus infection. This work provides a sensitive and accurate immunoassay technology for on-site virus detection and disease diagnosis compatible with wearable integration.


Asunto(s)
Hidrogeles , Subtipo H1N1 del Virus de la Influenza A , SARS-CoV-2 , Tecnología Inalámbrica , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Humanos , Hidrogeles/química , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Tecnología Inalámbrica/instrumentación , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Aerosoles , COVID-19/diagnóstico , COVID-19/virología , COVID-19/inmunología , Antígenos Virales/inmunología , Antígenos Virales/análisis , Virus Sincitiales Respiratorios/inmunología , Virus Sincitiales Respiratorios/aislamiento & purificación , Límite de Detección
16.
Mikrochim Acta ; 191(6): 306, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713247

RESUMEN

For early diabetes identification and management, the progression of an uncomplicated and exceedingly responsive glucose testing technology is crucial. In this study, we present a new sensor incorporating a composite of metal organic framework (MOF) based on cobalt, coated with boronic acid to facilitate selective glucose binding. Additionally, we successfully employed a highly sensitive electro-optical immunosensor for the detection of subtle changes in concentration of the diabetes biomarker glycated haemoglobin (HbA1c), using zeolitic imidazolate framework-67 (ZIF-67) coated with polydopamine which further modified with boronic acid. Utilizing the polymerization characteristics of dopamine and the NH2 groups, a bonding structure is formed between ZIF-67 and 4-carboxyphenylboronic acid. ZIF-67 composite served as an effective substrate for immobilising 4-carboxyphenylboronic acid binding agent, ensuring precise and highly selective glucose identification. The sensing response was evaluated through both electrochemical and optical methods, confirming its efficacy. Under optimized experimental condition, the ZIF-67 based sensor demonstrated a broad detection range of 50-500 mg dL-1, a low limit of detection (LOD) of 9.87 mg dL-1 and a high correlation coefficient of 0.98. Furthermore, the 4-carboxyphenylboronic acid-conjugated ZIF-67-based sensor platform exhibited remarkable sensitivity and selectivity in optical-based detection for glycated haemoglobin within the clinical range of 4.7-11.3%, achieving a LOD of 3.7%. These findings highlight the potential of the 4-carboxyphenylboronic acid-conjugated ZIF-67-based electro-optical sensor as a highly sensitive platform for diabetes detection.


Asunto(s)
Glucemia , Ácidos Borónicos , Diabetes Mellitus , Hemoglobina Glucada , Imidazoles , Límite de Detección , Estructuras Metalorgánicas , Zeolitas , Ácidos Borónicos/química , Zeolitas/química , Estructuras Metalorgánicas/química , Imidazoles/química , Humanos , Hemoglobina Glucada/análisis , Glucemia/análisis , Diabetes Mellitus/sangre , Diabetes Mellitus/diagnóstico , Nanopartículas/química , Técnicas Biosensibles/métodos , Indoles/química , Polímeros/química , Técnicas Electroquímicas/métodos
17.
Mikrochim Acta ; 191(6): 307, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713296

RESUMEN

An assay that integrates histidine-rich peptides (HisRPs) with high-affinity aptamers was developed enabling the specific and sensitive determination of the target lysozyme. The enzyme-like activity of HisRP is inhibited by its interaction with a target recognized by an aptamer. In the presence of the target, lysozyme molecules progressively assemble on the surface of HisRP in a concentration-dependent manner, resulting in the gradual suppression of enzyme-like activity. This inhibition of HisRP's enzyme-like activity can be visually observed through color changes in the reaction product or quantified using UV-visible absorption spectroscopy. Under optimal conditions, the proposed colorimetric assay for lysozyme had a detection limit as low as 1 nM and exhibited excellent selectivity against other nonspecific interferents. Furthermore, subsequent research validated the practical applicability of the developed colorimetric approach to saliva samples, indicating that the assay holds significant potential for the detection of lysozymes in samples derived from humans.


Asunto(s)
Colorimetría , Muramidasa , Saliva , Muramidasa/análisis , Muramidasa/química , Muramidasa/metabolismo , Colorimetría/métodos , Humanos , Saliva/química , Saliva/enzimología , Límite de Detección , Péptidos/química , Aptámeros de Nucleótidos/química , Proteínas/análisis , Técnicas Biosensibles/métodos , Histidina/análisis , Histidina/química
18.
Mikrochim Acta ; 191(6): 305, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713444

RESUMEN

A multifunctional surface-enhanced Raman scattering (SERS) platform integrating sensitive detection and drug resistance analysis was developed for Gram-positive bacteria. The substrate was based on self-assembled Ti3C2Tx@Au NPs films and capture molecule phytic acid (IP6) to achieve specific capture of Gram-positive bacteria and different bacteria were analyzed by fingerprint signal. It had advantages of good stability and homogeneity (RSD = 8.88%). The detection limit (LOD) was 102 CFU/mL for Staphylococcus aureus and 103 CFU/mL for MRSA, respectively. A sandwich structure was formed on the capture substrate by signal labels prepared by antibiotics (penicillin G and vancomycin) and non-interference SERS probe molecules (4-mercaptobenzonitrile (2223 cm-1) and 2-amino-4-cyanopyridine (2240 cm-1)) to improve sensitivity. The LOD of Au NPs@4-MBN@PG to S. aureus and Au NPs@AMCP@Van to MRSA and S. aureus were all improved to 10 CFU/mL, with a wide dynamic linear range from 108 to 10 CFU/mL (R2 ≥ 0.992). The SERS platform can analyze the drug resistance of drug-resistant bacteria. Au NPs@4-MBN@PG was added to the substrate and captured MRSA to compare the SERS spectra of 4-MBN. The intensity inhomogeneity of 4-MBN at the same concentrations of MRSA and the nonlinearity at the different concentrations of MRSA revealed that MRSA was resistant to PG. Finally, the SERS platform achieved the determination of MRSA in blood. Therefore, this SERS platform has great significance for the determination and analysis of Gram-positive bacteria.


Asunto(s)
Antibacterianos , Oro , Límite de Detección , Nanopartículas del Metal , Espectrometría Raman , Staphylococcus aureus , Titanio , Espectrometría Raman/métodos , Oro/química , Antibacterianos/farmacología , Antibacterianos/química , Titanio/química , Nanopartículas del Metal/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Vancomicina/farmacología , Vancomicina/química , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Penicilina G/farmacología , Penicilina G/química , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/aislamiento & purificación
19.
Mikrochim Acta ; 191(6): 310, 2024 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-38714566

RESUMEN

A ratiometric fluorescence sensor has been established based on dual-excitation carbon dots (D-CDs) for the detection of flavonoids (morin is chosen as the typical detecting model for flavonoids). D-CDs were prepared using microwave radiation with o-phenylenediamine and melamine and exhibit controllable dual-excitation behavior through the regulation of their concentration. Remarkably, the short-wavelength excitation of D-CDs can be quenched by morin owing to the inner filter effect, while the long-wavelength excitation remains insensitive, serving as the reference signal. This contributes to the successful design of an excitation-based ratiometric sensor. Based on the distinct and differentiated variation of excitation intensity, morin can be determined from 0.156 to 110 µM with a low detection limit of 0.156 µM. In addition, an intelligent and visually lateral flow sensing device is developed for the determination  of morin content in real samples with satisfying recoveries, which indicates the potential application for human health monitoring.


Asunto(s)
Carbono , Flavonoides , Límite de Detección , Nitrógeno , Impresión Tridimensional , Puntos Cuánticos , Espectrometría de Fluorescencia , Flavonoides/análisis , Flavonoides/química , Carbono/química , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Nitrógeno/química , Colorantes Fluorescentes/química , Humanos , Flavonas
20.
Mikrochim Acta ; 191(6): 309, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714599

RESUMEN

Copper-doped carbon dots and aminated carbon nanotubes (Cu-CDs/NH2-CNTs) nanocomposites were synthesized by a one-step growth method, and the composites were characterized for their performance. An electrochemical sensor for sensitive detection of bisphenol A (BPA) was developed for using Cu-CDs/NH2-CNTs nanocomposites modified with glassy carbon electrodes (GCE). The sensor exhibited an excellent electrochemical response to BPA in 0.2 M PBS (pH 7.0) under optimally selected conditions. The linear range of the sensor for BPA detection was 0.5-160 µM, and the detection limit (S/N = 3) was 0.13 µM. Moreover, the sensor has good interference immunity, stability and reproducibility. In addition, the feasibility of the practical application of the sensor was demonstrated by the detection of BPA in bottled drinking water and Liu Yang River water.


Asunto(s)
Compuestos de Bencidrilo , Cobre , Técnicas Electroquímicas , Electrodos , Límite de Detección , Nanotubos de Carbono , Fenoles , Contaminantes Químicos del Agua , Compuestos de Bencidrilo/análisis , Fenoles/análisis , Fenoles/química , Nanotubos de Carbono/química , Cobre/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Contaminantes Químicos del Agua/análisis , Agua Potable/análisis , Puntos Cuánticos/química , Carbono/química , Ríos/química
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