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1.
Food Chem ; 322: 126778, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32305007

RESUMO

Zearalenone (ZEN) is highly toxic to humans, and therefore, development of sensitive and effective methods for ZEN quantification in cereal crops is particularly important. Here, an innovative photoelectrochemical (PEC) aptasensor based on simply in-situ conjugated composites of zinc oxide-nitrogen doped graphene quantum dots (ZnO-NGQDs) was constructed. On addition of NGQDs, the composites displayed higher PEC signal with 8.8-fold enhancement than pure ZnO nanoparticles. A sensitive and selective PEC aptasensor was fabricated by combining the composites with ZEN aptamer, which yielded an excellent analytical performance for ZEN detection, with a wide linear range of 1.0 × 10-13-1.0 × 10-7 g mL-1 and a low detection limit of 3.3 × 10-14 g mL-1. Good recoveries were obtained using the PEC aptasensor, which were consistent with those obtained using the national standard method (HPLC-MS). Finally, ZEN in mildewing cereal crops was monitored with the PEC aptasensor, exhibiting good potential for application in cereal crops for early diagnosis.


Assuntos
Aptâmeros de Nucleotídeos/química , Grão Comestível/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Fotoquímica/métodos , Zearalenona/análise , Grão Comestível/microbiologia , Farinha/análise , Farinha/microbiologia , Grafite/química , Limite de Detecção , Óxido Nítrico/química , Pontos Quânticos , Óxido de Zinco/química
2.
Food Chem ; 321: 126697, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244141

RESUMO

Based on colloidal gold and broad-spectrum monoclonal antibody that binds to zeranol and its five analogues with high sensitivity, a lateral flow immunochromatographic assay (LFIA) in a competitive format was developed to specifically determine residues of zeranol, an illegal growth promoter in livestock. In this study, the assay had high sensitivity and was broad-spectrum only for zeranol and its five analogues, and the results were obtained within 10 min without needing sophisticated procedures. The cutoff values for zeranol and its five analogues were 10 ng/mL, and the IC50 values for zeranol, ß-zearalanol, zearalanone, α-zearalenol, ß-zearalenol and zearalenone were 1.250, 1.800, 1.775, 1.225, 1.709 and 1.319 ng/mL, respectively. The recovery rates were ranged from 85.6 to 93.9%, with the coefficient of variations less than 12.4%. The results demonstrated that the LFIA could be used for rapid, simultaneous, semi-quantitative and quantitative detection of residues of zeranol and its five analogous in milk.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Imunoensaio/métodos , Leite/química , Zeranol/análise , Animais , Anticorpos Monoclonais/imunologia , Desenho de Equipamento , Análise de Alimentos/instrumentação , Coloide de Ouro/química , Imunoensaio/instrumentação , Sensibilidade e Especificidade , Zearalenona/análise , Zeranol/análogos & derivados , Zeranol/imunologia
3.
J Chromatogr A ; 1620: 461026, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32178860

RESUMO

Sensitive and specific analysis of zearalenone (ZEN) mycotoxin in cereals for ensuring food safety is critical and remains challenging. Herein, a new gold nanoparticles @aptamer-functionalized hybrid affinity monolithic column was proposed and employed for online specific recognition of ZEN by HPLC. Characterization on the morphology, Brunauer-Emmett-Teller (BET) surface area mechanical stability and specific performance of the obtained affinity monolith were investigated. A super-high aptamer coverage density could reach 3636 pmol/µL, which is preferable to gain an effective analysis of ZEN with high specificity and a low interference of co-existed substances including typical α-Zearalenol (α-ZOL) and Aflatoxin B1 (AFB1). The sensitive recognition of trace ZEN was obtained with the limit of detection (LOD) as low as 0.05 ng/mL. Applied to real cereal samples, satisfactory recoveries were obtained in the range of 91.6 ± 1.4%-97.8 ± 2.6% (n = 3) in corn, 93.8 ± 3.1%-95.0 ± 3.6% (n = 3) in wheat, and 90.9 ± 4.7%-94.7 ± 3.8% (n = 3) in rice, respectively. The results on quantitative analysis were similar to that of LC-MS and better than that obtained by using immunoaffinity column (IAC) or molecularly imprinted polymer (MIP). This protocol provided an efficient access to high-efficient online specific recognition of ZEN in cereals by using such an aptamer-affinity capillary monolithic column.


Assuntos
Aptâmeros de Nucleotídeos/química , Ouro/química , Nanopartículas Metálicas/química , Sistemas On-Line , Zearalenona/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Grão Comestível/química , Contaminação de Alimentos/análise , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Permeabilidade , Reprodutibilidade dos Testes , Triticum/química , Zea mays/química
4.
Talanta ; 209: 120555, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892075

RESUMO

A novel magnetic surface molecular imprinted polymers with 2, 4, 6-trisacrylamido-3, 5-triazine (TAT) as a functional monomer was successfully synthesized and used for the enrichment and determination of zearalenone. The molecular imprinting is reported herein at first time for application of zearalenone in wheat. The magnetic imprinted materials possessed excellent magnetism and uniform appearance, which were characterized by fourier transform infared spectroscopy and transmission electron microscope. The results proved the magnetic molecular imprinted polymers was successfully prepared. The magnetic molecular imprinted polymers exhibited satisfactory sensitivity, stability and potential reusability. The binding affinity was investigated by selectivity experiment, which possessed high selectivity. To obtain the optimal application conditions, the amount of adsorption, extraction time, elution solvent and time were optimized. The limited detection of zearalenone was 0.55 ng g-1 and the recoveries of zearalenone were 92.1-96.0%. The relative standard deviation was lower than 5.4%. This indicated that a simple, efficient and low-cost method was established and successfully applied in spiked wheat sample.


Assuntos
Imãs/química , Impressão Molecular/métodos , Polímeros/química , Triticum/química , Zearalenona/análise , Acrilamidas/química , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Triazinas/química , Zearalenona/isolamento & purificação
5.
J Agric Food Chem ; 68(7): 2193-2200, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31976658

RESUMO

Various mycotoxins widely co-exist in agro-products, and their combined effects cause toxicity and potential carcinogenicity to humans and animals. In this work, we developed an economical and sensitive quantum dots (QDs)/QD microbead (QDs/QB)-based multiplex immunochromatographic assay (mICA) for the rapid detection of fumonisin B1 (FB1), zearalenone (ZEN), and ochratoxin A (OTA) without the building-up process of mycotoxin conjugates. QDs and QBs were selected as fluorescent reporters and conjugated with antimycotoxin monoclonal antibodies for improving sensitivity. Furthermore, phage-displayed FB1, ZEN, and OTA mimotope peptide-based soluble and monovalent fusions to maltose-binding protein (MBP) were applied onto the test line of the mICA as the mimetic coating antigen. Under the optimized conditions, the visual detection limits (vLODs) of peptide-MBP-based mICA could be obtained as 0.25 ng/mL for FB1, 3.0 ng/mL for ZEN, and 0.5 ng/mL for OTA within 10 min. The results for spiked real sample detection indicate good accuracy, reproducibility, and practicability. In addition, the proposed mICA was comparable with ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) in terms of reliability in detecting FB1, ZEN, and OTA using natural samples. From the point of promoting commercial production, these time-saving and low-cost peptide-MBP antigens applied in ICA might provide promising potential for promoting productivity and decreasing the cost of production.


Assuntos
Fumonisinas/análise , Imunoensaio/métodos , Ocratoxinas/análise , Zearalenona/análise , Contaminação de Alimentos/análise , Imunoensaio/economia , Imunoensaio/instrumentação , Limite de Detecção , Proteínas Ligantes de Maltose/química , Pontos Quânticos/química
6.
Anal Bioanal Chem ; 412(1): 81-91, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31953713

RESUMO

Methods for detecting mycotoxins are very important because of the great health hazards of mycotoxins. However, there is a high background and low signal-to-noise ratio in real-time sensing, and therefore it is difficult to meet the fast, accurate, and convenient requirements for control of food quality. Here we constructed a quantitative fluorescence image analysis based on multicolor upconversion nanocrystal (UCN)-encoded microspheres for detection of ochratoxin A and zearalenone. The background-free encoding image signal of UCN-doped microspheres was captured by fluorescence microscopy under near-infrared excitation, whereas the detection image signal of phycoerythrin-labeled secondary antibodies conjugated to the microspheres was captured under blue light excitation. We custom-wrote an algorithm to analyze the two images for the same sample in 10 s, and only the gray value in the red channel of the secondary probe confirmed the quantity. The results showed that this novel detection platform performed feasible and reliable fluorescence image measurements by this method. Additionally, the limit of detection of was 0.34721 ng/mL for ochratoxin A and 0.41162 ng/mL for zearalenone. We envision that this UCN encoding strategy will be usefully applied for fast, accurate, and convenient testing of multiple food contaminants to ensure the safety of the food.


Assuntos
Microesferas , Ocratoxinas/análise , Zearalenona/análise , Contaminação de Alimentos/análise , Imunoensaio/métodos , Limite de Detecção , Nanopartículas/química , Razão Sinal-Ruído
7.
Mycotoxin Res ; 36(1): 41-62, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31346981

RESUMO

Mycotoxins are difficult to monitor continuously, and a tool to assess the risk would help to judge if there is a particular risk due to the inclusion of certain feed ingredients. For this, the toxin contents of 97 commercial fish feeds have been estimated, and the most prominent toxins in fish feed are calculated to be deoxynivalenol, zearalenone, fumonisins and enniatins. These pose a risk to fish well-being, as can be calculated by the Bayesian models for determining the critical concentrations 5% (CC5) for the different toxins. Besides fishmeal, wheat, soybean products and corn are regularly used as fish feed ingredients. The calculated scenarios show that fish are at high risk of toxin contamination if feed ingredients of low quality are chosen for feed production. Due to this, specific maximum allowable levels for several mycotoxins in fish feeds should be established.


Assuntos
Ração Animal/análise , Contaminação de Alimentos , Micotoxinas/análise , Medição de Risco , Animais , Aquicultura , Aspergillus/metabolismo , Peixes , Fumonisinas/análise , Fumonisinas/toxicidade , Fusarium/metabolismo , Micotoxinas/toxicidade , Ocratoxinas/análise , Ocratoxinas/toxicidade , Penicillium/metabolismo , Tricotecenos/análise , Tricotecenos/toxicidade , Triticum/microbiologia , Zea mays/microbiologia , Zearalenona/análise , Zearalenona/toxicidade
8.
J Sci Food Agric ; 100(3): 1118-1123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31667844

RESUMO

BACKGROUND: Dairy farming feed can be contaminated with mycotoxins, affecting animals' health and milk quality. Dairy farming is also prone to occupational exposure to mycotoxins, and feed is recognized as a source of contamination in the workplace. An exploratory study was developed in a dairy farm located in Portugal intending to assess the mycotoxins present in the feed. RESULTS: All the samples analyzed presented contamination by at least two mycotoxins and up to a maximum of 13 mycotoxins in the same sample. Zearalenone (ZEA) was detected in all the samples (n = 10) followed by deoxynivalenol (DON), which was reported in eight samples, and ochratoxin A (OTA), reported in five samples. CONCLUSION: The results point to the possible contamination of milk by several mycotoxins and raise the possibility of occupational exposure to mycotoxins due to feed contamination. An adequate One Health approach for dairy production should address these issues through effective preventive actions such as avoiding the use of feed contaminated with mycotoxins. This represents an important challenge due to climate change. It requires proper attention and accurate management measures. © 2019 Society of Chemical Industry.


Assuntos
Doenças dos Trabalhadores Agrícolas/etiologia , Ração Animal/análise , Leite/química , Micotoxinas/análise , Exposição Ocupacional/efeitos adversos , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Animais , Bovinos , Fazendeiros/estatística & dados numéricos , Fazendas , Contaminação de Alimentos/análise , Humanos , Micotoxinas/toxicidade , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Ocratoxinas/análise , Ocratoxinas/toxicidade , Portugal , Zearalenona/análise , Zearalenona/toxicidade
9.
Food Chem ; 305: 125429, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505415

RESUMO

A simple and rapid magnetic solid-phase extraction (MSPE) method using PEGylated multi-walled carbon nanotubes magnetic nanoparticles (PEG-MWCNTs-MNP) as absorbents is proposed for isolation and enrichment of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), aflatoxin M1 (AFM1), aflatoxin M2 (AFM2), ochratoxin A (OTA), zearalenone (ZEA), zearalanone (ZAN), α-zeralanol (α-ZAL), ß-zeralanol (ß-ZAL), α-zeralenol (α-ZOL), and ß-zeralenol (ß-ZOL) from liquid milk. Combined with ultra-high performance liquid chromatography Q-Exactive high resolution mass spectrometry, simultaneous qualification of these mycotoxins was achieved with sensitivity and specificity. The proposed method showed a good linearity (R2 ≥ 0.995), high sensitivity (limit of detection in the range of 0.005-0.050 µg/kg and limit of quantification in the range of 0.015-0.150 µg/kg), adequate recovery (81.8-106.4%), and good repeatability (intra-day precision in the range of 2.1-8.5% and inter-day precision in the range of 3.9-11.7%). It has been successfully applied to the determination of 13 mycotoxins in real liquid milk samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Leite/química , Micotoxinas/análise , Extração em Fase Sólida/métodos , Aflatoxinas/análise , Animais , Magnetismo , Nanotubos de Carbono , Ocratoxinas/análise , Sensibilidade e Especificidade , Zearalenona/análise
10.
Talanta ; 208: 120445, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816708

RESUMO

Multi-channel capillaries (MC) formed from thousands individual microcapillaries with diameters ranging 10-100 µm are of a great interest for their use as platforms for molecular imprinting due to their relatively large surface area, high mechanical stability and possibility of facile integration in sensor systems. The manuscript proposes a new format of immunoassay based on imprinted protein immobilized on a MC inner surface modified with poly-l-lysine. The combination of the environmentally friendly, easy-to-produce and cheap recognition element with the carrier allowing to increase the assay sensitivity makes the described technique a perspective alternative for the existing screening tests. Two bioimprinting approaches were described. The imprinted protein (ovalbumin, OVA) primarily prepared separately and later immobilized on a MC structure was compared to the imprinted OVA directly prepared on the MC surface. Detection of a food contaminant zearalenone was chosen as a proof-of-concept. In a case of the immobilization of the primarily prepared imprinted OVA the reached limit of detection (LOD) was 0.8 ng/mL, and for the in-situ imprinted OVA the LOD was 0.12 ng/mL. The sensitivity of the developed bioimprinted assay was comparable to the commercially available ELISA kits for ZEN detection. The OVA in-situ imprinted on the MC surface was tested for the detection of ZEN in artificially spiked wheat samples. The high recovery values (88-112%) and good repeatability (RSD of 8.5-9.6%) were demonstrated allowing to conclude that the IPs-based MC-ELISA is a promising tool for analysis of the mycotoxin in complex matrices.


Assuntos
Contaminação de Alimentos/análise , Imunoensaio/métodos , Impressão Molecular , Ovalbumina/química , Triticum/química , Zearalenona/análise , Vidro , Peroxidase do Rábano Silvestre/química , Proteínas Imobilizadas/química , Polilisina/química , Soroalbumina Bovina/química , Zearalenona/química
11.
Food Chem Toxicol ; 136: 111081, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31883987

RESUMO

Mycotoxins are toxic compounds produced by the metabolism of certain fungi that threaten the food and agricultural industry. Over hundreds of mycotoxins, one of the most common toxins, zearalenone (ZEN), has toxic effects on human and animal health due to its mutagenicity, treatogenicity, carcinogenicity, nephrotoxicity, immunotoxicity, and genotoxicity. In this work, attenuated internal reflection spectroscopic ellipsometry (AIR-SE) combined with the signal amplification via surface plasmon resonance conditions that were proved to be a highly sensitive analytical tool in bio-sensing was developed for the sensitive and selective ZEN detection in cereal products such as corn, wheat, rice, and oat. Combined with the oligonucleotide aptamer for ZEN recognition, our proposed method showed good performance with yielding 0.08 ng/mL LOD and 0.01-1000 ng/mL detection range. A mini-review was also introduced in, to compare various methods for ZEN detection.


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Análise Espectral/métodos , Zearalenona/análise , Aptâmeros de Nucleotídeos/análise , Oryza/química , Análise Espectral/instrumentação , Triticum/química , Zea mays/química
12.
Mikrochim Acta ; 187(1): 75, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31863215

RESUMO

An impedimetric immunoassay was designed for ultrasensitive determination of zearalenone (ZEN). It is making use of the peroxidase-like activity of strip-shaped Co3O4 (ssCo3O4) which catalyzes the oxidation of 4-chloro-1-naphthol to produce an insoluble precipitate in the presence of H2O2. The precipitate is electrically nonconductive and accumulates on the electrode, thereby retarding the electron transfer from the redox probe ferro/ferricyanide to the surface of electrode. This amplifies the impedimetric signal in accordance with logarithm of the concentration of ZEN. The electrode was further modified with TiO2 mesocrystals (TiO2 MCs) which improve the capture of more analytes and increase the performance of the immunoassay. Under optimized experimental condition, the impedimetric signal increased linearly with the logarithm of the ZEN concentration range between 0.1 fg·mL-1 to 10 pg·mL-1. The detection limit is of 33 ag· mL-1. Graphical abstractThis work describes an impedimetric immunoassay based on the use of strip-shaped Co3O4 that catalyzes the production of an insoluble precipitate in the presence of H2O2 on the surface of a glassy carbon electrode. The effect was used for signal amplification in an electrochemical immunoassay for zearalenone.


Assuntos
Cobalto/química , Imunoensaio , Óxidos/química , Peroxidase/química , Fitas Reagentes/química , Zearalenona/análise , Cobalto/metabolismo , Eletrodos , Humanos , Oxirredução , Óxidos/metabolismo , Tamanho da Partícula , Peroxidase/metabolismo , Fitas Reagentes/metabolismo , Propriedades de Superfície , Zearalenona/metabolismo
13.
Mikrochim Acta ; 186(12): 765, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713694

RESUMO

An enzyme-free fluorometric assay is described for the determination of zearalenone (ZEN). The method combines (a) catalyzed hairpin assembly (CHA), (b) ultrahigh fluorescent light-up G-rich DNA sequences in proximity to silver nanoclusters (Ag NCs), and (c) the use of aptamers (Apt). In the presence of ZEN, the inhibit sequence (Inh) is released from the aptamer-trigger sequence (Apt-T) via the binding of ZEN and the aptamer of Apt-T. The free Apt-T acts as a switch that opens the hairpins H1 and H2 to generate H1-H2 complex. The released Apt-T is available to trigger the next round of CHA between H1 and H2. Finally, the hybridization between H1 and the Ag NCs probe (P) causes the G-rich sequence to be in close proximity to the dark Ag NCs encapsulated by P. This leads to highly efficient lighting up of the Ag NCs and the production of amplified fluorescence with excitation/emission peaks at 575/628 nm. Under the optimized conditions, a linear correlation was observed with concentrations ranging from 1.3 pg mL-1 to 100 ng mL-1, and the limit of detection was 0.32 pg mL-1 (at S/N = 3). The method was successfully validated by analyzing maize and beer for levels of ZEN after a simple sample preparation procedure. Graphical abstractSchematic of the assay. The inhibit sequence (Inh) is released from aptamer-trigger sequence (Apt-T) via binding of ZEN and aptamer. The free Apt-T triggers catalyzed hairpin assembly (CHA).G-rich DNA is in proximity to silver nanoclusters (Ag NCs) and fluorescence intensity increases to detect ZEN.


Assuntos
Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Micotoxinas/análise , Espectrometria de Fluorescência/métodos , Zearalenona/análise , Aptâmeros de Nucleotídeos/genética , Cerveja/análise , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Contaminação de Alimentos/análise , Sequências Repetidas Invertidas , Limite de Detecção , Hibridização de Ácido Nucleico , Prata/química , Zea mays/química
14.
Mikrochim Acta ; 186(12): 748, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696359

RESUMO

A fluorometric lateral flow immunoassay (LFA) is described for the simultaneous determination of the mycotoxins aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON). The method is based on the use of CdSe/SiO2 quantum dot microbeads (QBs) with a mean diameter of 106 nm. These have strong red luminescence (with excitation/emission peaks at 365/622 nm) which results in enhanced sensitivity. The QBs binding with monoclonal antibodies (mAbs) as the signal probes can react specifically with AFB1, ZEN and DON, respectively. There is an inverse correlation between the fluorescence signal intensity of test line and the analyte content, which can realize the quantitative analysis of analytes within 15 min. The limits of detection in solution are 10, 80 and 500 pg mL-1 for AFB1, ZEN and DON, respectively. Besides, the average recoveries from spiked feed range from 85.5 to 119.0%, and the relative standard deviations are less than 16.4% for both intra- and inter-day assays. The method was used to analyze naturally contaminated feedstuff, and this resulted in a good agreement with data obtained by LC-MS/MS. Graphical abstractSchematic representation of a fluorometric method for the simultaneous determination of three mycotoxins. Quantum dot microbeads (QBs) binding with monoclonal antibodies (mAbs) are signal probes. There is an inverse correlation between the fluorescence intensity of test line and the analyte concentration.


Assuntos
Aflatoxina B1/análise , Imunoensaio/métodos , Micotoxinas/análise , Pontos Quânticos/química , Tricotecenos/análise , Zearalenona/análise , Aflatoxina B1/imunologia , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Compostos de Cádmio/química , Grão Comestível/química , Corantes Fluorescentes/química , Fluorometria/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Magnoliopsida/química , Microesferas , Micotoxinas/imunologia , Compostos de Selênio/química , Dióxido de Silício/química , Tricotecenos/imunologia , Zearalenona/imunologia
15.
Se Pu ; 37(8): 911-917, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642263

RESUMO

A liquid chromatography method was established for the determination of zearalanone (ZAN) raw material. The qualitative analysis of ZAN and its trace impurities was performed by ultra performance liquid chromatography-diode array detector (UPLC-DAD) and ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS), and the response factors of each impurity were calculated. The three main organic impurities in the ZAN raw material were identified as ß -zearalanol, α -zearalanol and a dehydration product of zearalanol with relative response factors of 0.5352, 0.8594 and 0.6973, respectively. The main component of the ZAN raw material was determined by the calibration factor normalization method. The purity of zearalanone was determined to be 99.6% with a standard deviation of 0.01%. This method can provide a technical support for the development of ZAN standard materials.


Assuntos
Zearalenona/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Análise de Componente Principal
16.
Wei Sheng Yan Jiu ; 48(4): 651-658, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601351

RESUMO

OBJECTIVE: To develop a highly sensitive immunochromatographic test card for zearalenone. METHODS: Gold nanoflowers(AuNFs) with a particle size of(116. 7±2. 0) nm and multiple branches was prepared and labeled to the zearalenone monoclonal antibody. Based on the gold nanoflower-labeled zearalenone monoclonal antibody(AuNF-ZEN-Mab), a zearalenone gold nanoflower immunochromatographic test card(ZEN-GFICT) was developed for the detection of food and feed. RESULTS: The detection sensitivities of ZEN-GFICT(contrast method) and(cancellation method) for ZEN standards were 0. 5 and 6 ng/mL, respectively, and the limit of detection(LOD) for actual samples were 5 and 60 µg/kg, respectively. It was 6 times(contrast method) and 4. 5 times(cancellation method) of the traditional ZEN nano gold immunochromatographic test card(ZEN-GICT). The total conformity of the ZEN-GFICT judgment result(contrast method and cancellation method) of 21 samples compared with those of the ELISA kit were 90. 5% and 90. 5%, respectively. CONCLUSION: The ZEN content in the sample with three intervals of less than 5 µg/kg, 5-60 µg/kg and more than 60 µg/kg could be screened by the ZEN-GFICT contrast method and the cancellation method. It is possible to screen samples with a low degree of ZEN contamination.


Assuntos
Zearalenona/análise , Contaminação de Alimentos , Limite de Detecção
17.
Int J Nanomedicine ; 14: 7695-7705, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571872

RESUMO

Background: Lateral flow assays (LFA) play an increasingly important role in the rapid detection of various pathogens, pollutants, and toxins. Purpose: To overcome the drawbacks of low sensitivity and poor quantification in LFA, we developed a new calorimetric LFA (CLFA) using gold nanocages (GNCs) due to their high photothermal conversion efficiency, good stability of photophysical properties, and stronger penetrating ability of NIR light. Methods: Thiol-polyethylene glycol-succinyl imide ester (HS-PEG-NHS) was modified onto GNCs, and the complex was conjugated with an antibody. Subsequently, the antibody-conjugated GNCs were analyzed by UV/Vis spectrophotometer, transmission electron microscope, high-resolution transmission electron microscope with energy dispersive spectrometer, dynamic light scattering instrument, and Atom force microscope. The GNC-based CLFA of alpha-fetoprotein (AFP) and zearalenone (ZEN), a food toxin, required nitrocellulose strips, a NIR laser source, and an infrared camera. Results: The GNC-labeled CLFA platform technique exhibited detection sensitivity, qualitative specificity, and quantitative accuracy. The superior performance of the technique was evident both in sandwich format detection of biomacromolecules (eg, AFP protein) or competitive format detection of small molecules (eg, ZEN). After optimizing various test parameters, GNC-labeled CLFA provided ca. 5-6-fold enhanced sensitivity, higher correlativity (R 2>0.99), and more favorable recovery (82-115%) when compared with visual LFA. Conclusion: GNC-labeled CLFA may be a promising detection platform with high sensitivity, specificity, and precision.


Assuntos
Calorimetria/métodos , Ouro/química , Imunoensaio/métodos , Luz , Nanopartículas/química , Temperatura , Animais , Humanos , Limite de Detecção , Camundongos , Nanopartículas/ultraestrutura , Sensibilidade e Especificidade , Zearalenona/análise , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/química
18.
Food Chem ; 301: 125281, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31382109

RESUMO

The need for safe and quality food, free from the presence of hazardous contaminants such as mycotoxins is an on-going and complex challenge. Cold atmospheric pressure plasma (CAPP) has the potential to contribute to achieving this goal. Decontamination efficacy of CAPP against six of the most common mycotoxins found in foods and feedstuffs was assessed herein. Concentration reduction of up to 66% was achieved in maize for both aflatoxin B1 and fumonisin B1. Degradation products were detected only in the case of aflatoxin B1 and zearalenone and were tested on human hepatocarcinoma cells with no increase in cytotoxicity observed. Analysis of treated maize revealed substantial changes to small molecular mass components of the matrix. While CAPP shows promise in terms of mycotoxin detoxification important questions concerning potential changes to the nutritional and safety status of the food matrix require further investigations.


Assuntos
Descontaminação/métodos , Contaminação de Alimentos/análise , Micotoxinas/química , Gases em Plasma/química , Aflatoxina B1/análise , Aflatoxina B1/química , Aflatoxina B1/toxicidade , Fumonisinas/análise , Fumonisinas/química , Fumonisinas/toxicidade , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Micotoxinas/análise , Micotoxinas/toxicidade , Zea mays/química , Zearalenona/análise , Zearalenona/química , Zearalenona/toxicidade
19.
ACS Appl Mater Interfaces ; 11(34): 31283-31290, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31389683

RESUMO

In this work, polydopamine-coated gold nanoparticles (Au@PDAs) were synthesized by the oxidative self-polymerization of dopamine (DA) on the surface of AuNPs and applied for the first time as a signal-amplification label in lateral flow immunoassays (LFIAs) for the sensitive detection of zearalenone (ZEN) in maize. The PDA layer functioned as a linker between AuNPs and anti-ZEN monoclonal antibody (mAb) to form a probe (Au@PDA-mAb). Compared with AuNPs, Au@PDA had excellent color intensity, colloidal stability, and mAb coupling efficiency. The limit of detection of the Au@PDA-based LFIA (Au@PDA-LFIA) was 7.4 pg/mL, which was 10-fold lower than that of the traditional AuNP-based LFIA (AuNP-LFIA) (76.1 pg/mL). The recoveries of Au@PDA-LFIA were 93.80-111.82%, with the coefficient of variation of 1.08-9.04%. In addition, the reliability of Au@PDA-LFIA was further confirmed by the high-performance liquid chromatography method. Overall, our study showed that PDA coating can chemically modify the surface of AuNPs through a simple method and can thus significantly improve the detection sensitivity of LFIA.


Assuntos
Ouro/química , Indóis/química , Nanopartículas Metálicas/química , Polímeros/química , Zea mays/química , Zearalenona/análise , Imunoensaio , Limite de Detecção
20.
J Chromatogr A ; 1604: 460475, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31466701

RESUMO

Enrichment, separation and purification are very important to accurately analyze mycotoxins in complicated samples. In the work, we developed a new enrichment, purification and high-performance liquid chromatography combined with fluorescence detector (HPLC-FLD) for aflatoxins B1 (AFB1), ochratoxin A (OTA) and Zearalenone (ZEN) assay using the macroporous magnetic 3D photonic crystal microspheres (3DPCMs). The conditions of enrichment and purification for mycotoxins have been optimized, which are as follows: pore size of 3DPCMs at 280 nm, 1:1 methanol:acetonitrile (v/v) as eluent, antibody concentrations at 60 µg/mL,60 µg/mL and 120 µg/mL for OTA, AFB1 and ZEN, respectively. The recovery rates in the rice, wheat and corn samples range from 70.01% to 100.12% and the relative standard deviation (RSD) range from 0.45% to 7.09%. The recovery rates used 3DPCMs are almost tenfold higher than that used non-macroporous PCMs in the same conditions. The developed method is simple, rapid (time including enrichment, purification and detection <2 h) and only requires small volume reagents (≤200 µL).


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Micotoxinas/análise , Fótons , Aflatoxina B1/análise , Aflatoxina B1/isolamento & purificação , Anticorpos/química , Cristalização , Fluorescência , Proteínas Imobilizadas/química , Micotoxinas/isolamento & purificação , Ocratoxinas/análise , Ocratoxinas/isolamento & purificação , Porosidade , Propriedades de Superfície , Zearalenona/análise , Zearalenona/isolamento & purificação
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