Detection Of Deoxynivalenol Research Articles

SERS-lateral flow immunoassay based on AuNR@Ag@SiO2-AuNP assembly for ultra-sensitive detection of deoxynivalenol in grain

In view of the serious harm and widespread pollution caused by deoxynivalenol (DON), it is crucial to quantify its presence in the food safety assessment process. Here, we designed a core-shell-satellite nano assembly structure as a probe, composed of an anisotropic AuNR@Ag core, an ultra-thin SiO2 layer and a high surface coverage AuNPs satellites, which showed outstanding SERS activity and high stability. Anti-DON antibodies were modified on the surface of the prepared core-shell-satellite nano-assembly structure as SERS immunoprobe for DON specific detection using SERS-based lateral flow immunoassay (LFIA) with the advantages of simplicity, rapidity, and high sensitivity. Under optimal conditions, the detection limit for detecting DON using the SERS-LFIA method was 0.053 fg/mL, and the linear detection ranged from 0.1 fg/mL to 1 μg/mL. The SERS-LFIA strips based on AuNR@Ag@SiO2-AuNP nanostructures demonstrated the great potential for quick quantitative DON detection, providing a reference for trace detection of highly toxin mycotoxins.

A highly sensitive SERS aptasensor using a novel truncated aptamer for the detection of Deoxynivalenol

Deoxynivalenol (DON) is a common mycotoxin in nature, which is not only widely distributed, but also can cause human and animal poisoning, posing a serious threat to food safety and social economy. Therefore, it is very important to develop a sensitive and stable method to detect DON. In this research, the optimal aptamer D40 was obtained by molecular docking prediction and truncation based on molecular docking results. Then, we labeled the Cy3 Raman reporter molecule with D40, as a capture probe for the aptasensor. Finally, the porous π-rich structure Cu@C derived from the thermal decomposition of CuBTC is combined with AuNPs to generate abundant hot spots, and the Cy3-aptamers are adsorbed to the composite by the π-π to produce sharp and significant Raman signals. In the presence of DON, Cy3-aptamers bind to DON specifically and dissociate from the composite material, and the Raman signal decreases. The prepared SERS aptasensor was capable of detecting DON in a wide range from 0.01 to 10000ng/mL with a detection limit of 4.56pg/mL, and the recovery rate of 94.42 ~ 107.04% was obtained in two real samples, which indicated that the aptasensor proposed in this study exhibited outstanding practical performance and had potential application value in the field of food safety.

A portable micro-nanochannel bio-3D printed liver microtissue biosensor for DON detection

We investigated a portable micro-nanochannel biosensor 3D-printed liver microtissues for rapid and sensitive deoxynivalenol (DON) detection. The screen-printed carbon electrode (SPCE) was modified with nanoporous anodic aluminum oxide (AAO), gold nanoparticles (AuNPs), and cytochrome C oxidase (COx) to enhance sensor performance. Gelatin methacrylate hydrogel, combined with hepatocellular carcinoma cells, formed the bioink for 3D printing. Liver microtissues were prepared through standardized and high-throughput techniques via bio-3D printing technology. These microtissues were immobilized onto modified electrodes to fabricate liver microtissue sensors. The peak current of this biosensor was positively correlated with DON concentration, as determined by cyclic voltammetry (CV), within a linear detection range of 2∼40 μg/mL. The standard curve equation is denoted by ICV(μA)= =18.76956+0.03107CDON(μg/mL), with a correlation coefficient R2 was 0.99471(n＝3). A minimum detection limit of 1.229 μg/mL was calculated from the formula, indicating the successful construction of a portable micro-nanochannel bio-3D printed liver microtissue biosensor. It provides innovative ideas for developing rapid and convenient instrumentation to detect mycotoxin hazards after grain production. It also holds significant potential for application in the prediction and assessment of post-production quality changes in grain.

Determination of deoxynivalenol (DON) by a label-free electrochemical immunosensor based on Ni[sbnd]Fe PBA nanozymes

Deoxynivalenol (DON) contamination in food products significantly threatens human health, necessitating a reliable and sensitive detection method. This study aims to develop a simple, low-cost, and effective electrochemical immunoassay method for detecting DON based on the nickel‑iron bimetallic Prussian blue analog (NiFe PBA). The NiFe PBA nanozymes with high peroxidase-like activity were synthesized using an environmentally friendly chemical precipitation method. In the presence of hydrogen peroxide (H2O2), the current change of thionine oxidation initiated by NiFe PBA nanozymes can be exploited to diagnose DON. Under optimal conditions, the proposed method achieved quantitative detection of DON in the range of 10–107 pg mL−1 with a detection limit of 4.5 pg mL−1 (S/N = 3), demonstrating excellent selectivity, reproducibility, and stability. In addition, the DON immunosensor provides satisfactory results for the detection in real samples, demonstrating the feasibility of the proposed sensor in detecting of DON in such products.

Cu2O nanoparticles with morphology-dependent peroxidase mimic activity: a novel colorimetric biosensor for deoxynivalenol detection.

Different morphological Cu2O nanoparticles including cube, truncated cube, and octahedron were successfully prepared by a selective surface stabilization strategy. The prepared cube Cu2O exhibited superior peroxidase-like activity over the other two morphological Cu2O nanoparticles, which can readily oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form visually recognizable color signals. Consequently, a sensitive and simple colorimetric biosensor was proposed for deoxynivalenol (DON) detection. In this biosensor, the uniform cube Cu2O was employed as the vehicle to label the antibody for the recognition of immunoreaction. The sensing strategy showed a detection limit as low as 0.01ng/mL, and a wide linear range from 2 to 100ng/mL. Concurrently, the approximate DON concentration can be immediately and conveniently observed by the vivid color changes. Benefiting from the high sensitivity and selectivity of the designed biosensor, the detection of DON in wheat, corn, and tap water samples was achieved, suggesting the bright prospect of the biosensor for the convenient and intuitive detection of DON in actual samples.

Dual-modal lateral flow immunoassay based on cauliflower-like ReS2@Pt core-shell nanospheres mediated ultra-sensitive detection of deoxynivalenol in food samples

Deoxynivalenol (DON) is a highly toxic secondary metabolite that poses a substantial threat to global human and animal health. However, existing detection technologies are often constrained by limited sensitivity, poor selectivity, or the high costs associated with instrumentation. Consequently, the development of rapid, low-cost, and highly sensitive biosensors for the detection of DON is of paramount importance for ensuring food safety. In this study, we synthesized the precursor of ReS₂ nanospheres using a relatively simple one-step hydrothermal method. Subsequently, Platinum (Pt) was grown in situ on the surface of the ReS₂ nanospheres via hydrothermal reduction, resulting in the formation of cauliflower-like ReS₂@Pt nanospheres. These spheres offer notable advantages, including strong colorimetric signal brightness and high anti-body loading efficiency. Surface modification with platinum significantly enhances peroxidase-like activity, broadening the detection range and improving sensitivity. Leveraging this innovation, we developed Colorimetric-LFIA (CR-LFIA) and Catalytic-LFIA (CL-LFIA) assays. Under optimized conditions, the limit of detection (LOD) for DON was determined to be 0.018 ng/mL for CR-LFIA and 6.5 pg/mL for CL-LFIA, representing 5 times and 16 times improvement over AuNPs-based LFIA (0.111 ng/mL), respectively. Moreover, the detection linear range of CL-LFIA is expanded by 2.5 times compared to CR-LFIA. Validation with real samples demonstrated recovery rates between 90.33% and 110.64%, affirming method stability and repeatability. The developed dual-modal LFIA detection system (D-LFIA) employing ReS2@Pt NPs holds promise for ultra-sensitive detection, with potential applications in expanding the detection range of various substances.

A Surface-Enhanced Raman Spectroscopy-Based Aptasensor for the Detection of Deoxynivalenol and T-2 Mycotoxins.

The quality of food is one of the emergent points worldwide. Many microorganisms produce toxins that are harmful for human and animal health. In particular, mycotoxins from Fusarium fungi are strictly controlled in cereals. Simple and robust biosensors are necessary for 'in field' control of the crops and processed products. Nucleic acid-based sensors (aptasensors) offer a new era of point-of-care devices with excellent stability and limits of detection for a variety of analytes. Here we report the development of a surface-enhanced Raman spectroscopy (SERS)-based aptasensor for the detection of T-2 and deoxynivalenol in wheat grains. The aptasensor was able to detect as low as 0.17% of pathogen fungi in the wheat grains. The portable devices, inexpensive SERS substrate, and short analysis time encourage further implementation of the aptasensors outside of highly equipped laboratories.

Ultrasensitive Electrochemiluminescence Biosensing Platform Based on Polymer Dots with Aggregation-Induced Emission for Dual-Biotoxin Assay.

Multitarget assay has always been a hot topic in electrochemiluminescence (ECL) methods. Herein, a "on-off-on" ECL aptasensor was developed for the ultrasensitive and sequential detection of possible biological warfare agents, deoxynivalenol (DON) and abrin (ABR). As a luminophore, polymer dots (Pdots) with aggregation-induced emission exhibit high ECL efficiency in the aptasensor, i.e., the signal "on" state. The DON assays mainly depend on ECL quenching due to the efficient quenching effect between ferrocene-H2-ferrocene (Fc-H2-Fc) and Pdots, i.e., the signal "off" state. When the aptasensor is incubated with the oligonucleotide sequence S2 to replace Fc-H2-Fc, obvious ECL recovery occurs, i.e., the signal "on" state, which can be used to sequentially detect ABR. The limit of detection (LOD) for DON is 0.73 fg·mL-1 in the range of 5.0 to 50 ng·mL-1; and the LOD for ABR is ∼0.38 pg·mL-1 in the range of 1.25 pg·mL-1 to 1.25 μg·mL-1. The as-designed ECL aptasensor exhibits good stability and reproducibility, high specificity, and favorable practicality. Therefore, this work provides a new approach for assays of DON and ABR in food safety and can be used as a model to design an ultrasensitive ECL biosensor for multitarget detection.

Enzyme Cascade Amplification-Based Immunoassay Using Alkaline Phosphatase-Linked Single-Chain Variable Fragment Fusion Tracer and MnO2 Nanosheets for Detection of Deoxynivalenol in Corn Samples.

Deoxynivalenol (DON) is a common mycotoxin that contaminates cereals. Therefore, the development of sensitive and efficient detection methods for DON is essential to guarantee food safety and human health. In this study, an enzyme cascade amplification-based immunoassay (ECAIA) using a dual-functional alkaline phosphatase-linked single-chain fragment variable fusion tracer (scFv-ALP) and MnO2 nanosheets was established for DON detection. The scFv-ALP effectively catalyzes the hydrolysis of ascorbyl-2-phosphate (AAP) to produce ascorbic acid (AA). This AA subsequently interacts with MnO2 nanosheets to initiate a redox reaction that results in the loss of oxidizing properties of MnO2. In the absence of ALP, MnO2 nanosheets can oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to produce the blue oxidized product of TMB, which exhibits a signal at a wavelength of 650 nm for quantitative analysis. After optimization, the ECAIA had a limit of detection of 0.45 ng/mL and a linear range of 1.2-35.41 ng/mL. The ECAIA exhibited good accuracy in recovery experiments and high selectivity for DON. Moreover, the detection results of the actual corn samples correlated well with those from high-performance liquid chromatography. Overall, the proposed ECAIA based on the scFv-ALP and MnO2 nanosheets was demonstrated as a reliable tool for the detection of DON in corn samples.

Smartphone-enabled colorimetric immunoassay for deoxynivalenol based on Mn2+-mediated aggregation of AuNPs

Deoxynivalenol (DON) is a common mycotoxin in food that mainly pollutes grain crops and feeds, such as barley, wheat and corn. DON has caused widespread concern in the field of food and feed safety. In this study, a colorimetric immunoassay was proposed based on the aggregation of gold nanoparticles (AuNPs) due to the decomposition of Mn2+ from gold-coated manganese dioxide (AuNP@MnO2) nanosheets. In this study, 2-(dihydrogen phosphate)-l-ascorbic acid (AAP) was hydrolyzed by alkaline phosphatase (ALP) and converted to ascorbic acid (AA). Then, AuNP@MnO2 was reduced to Mn2+ and AuNPs aggregation occurred. Using the unique optical characteristics of AuNPs and AuNP@MnO2, visible color changes realized simple detection of DON with high sensitivity and portability. With increasing DON content, the color changed more obviously. To quantitatively detect DON, pictures can be taken and the blue value can be read by a smartphone. The detection limit (Ic10) of this method was 0.098 ng mL−1, which was 326 times higher than that of traditional competitive ELISA, and the detection range was 0.177–6.073 ng mL−1. This method exhibited high specificity with no cross-reaction in other structural analogs. The average recovery rate of DON in corn flour samples was 89.1 %–110.2 %, demonstrating the high accuracy and stability of this assay in actual sample detection. Therefore, the colorimetric immunoassay can be used for DON-related food safety monitoring.

Rapid, on-site quantitative determination of mycotoxins in grains using a multiple time-resolved fluorescent microsphere immunochromatographic test strip

The label probe plays a crucial role in enhancing the sensitivity of lateral flow immunoassays. However, conventional fluorescent microspheres (FMs) have limitations due to their short fluorescence lifetime, susceptibility to background fluorescence interference, and inability to facilitate multi-component detection. In this study, carboxylate-modified Eu(III)-chelate-doped polystyrene nanobeads were employed as label probes to construct a multiple time-resolved fluorescent microsphere-based immunochromatographic test strip (TRFM-ICTS). This novel TRFM-ICTS facilitated rapid on-site quantitative detection of three mycotoxins in grains: Aflatoxin B1 (AFB1), Zearalenone (ZEN), and Deoxynivalenol (DON). The limit of detection (LOD) for AFB1, ZEN, and DON were found to be 0.03 ng/g, 0.11 ng/g, and 0.81 ng/g, respectively. Furthermore, the TRFM-ICTS demonstrated a wide detection range for AFB1 (0.05–8.1 ng/g), ZEN (0.125–25 ng/g), and DON (1.0–234 ng/g), while maintaining excellent selectivity. Notably, the test strip exhibited remarkable stability, retaining its detection capability even after storage at 4 °C for over one year. Importantly, the detection of these mycotoxins relied solely on simple manual operations, and with a portable reader, on-site detection could be accomplished within 20 min. This TRFM-ICTS presents a promising solution for sensitive on-site mycotoxin detection, suitable for practical application in various settings due to its sensitivity, accuracy, simplicity, and portability.

Dual-plasmonic CuS@Au heterojunctions synergistic enhanced photothermal and colorimetric dual signal for sensitive multiplexed LFIA

Multiplexed immunodetection, which achieves qualitative and quantitative outcomes for multiple targets in a single-run process, provides more sufficient results to guarantee food safety. Especially, lateral flow immunoassay (LFIA), with the ability to offer multiple test lines for analytes and one control line for verification, is a forceful candidate in multiplexed immunodetection. Nevertheless, given that single-signal mode is incredibly vulnerable to interference, further efforts should be engrossed on the combination of multiplexed immunodetection and multiple signals. Photothermal signal has sparked significant excitement in designing immunosensors. In this work, by optimizing and comparing the amount of gold, CuS@Au heterojunctions (CuS@Au HJ) were synthesized. The dual-plasmonic metal-semiconductor hybrid heterojunction exhibits a synergistic photothermal performance by increasing light absorption and encouraging interfacial electron transfer. Meanwhile, the colorimetric property is synergistic enhanced, which is conducive to reduce the consumption of antibodies and then improve assay sensitivity. Therefore, CuS@Au HJ are suitable to be constructed in a dual signal and multiplexed LFIA (DSM-LFIA). T-2 toxin and deoxynivalenol (DON) were used as model targets for the simulated multiplex immunoassay. In contrast to colloidal gold-based immunoassay, the built-in sensor has increased sensitivity by ≈ 4.42 times (colorimetric mode) and ≈17.79 times (photothermal mode) for DON detection and by ≈ 1.75 times (colorimetric mode) and ≈13.09 times (photothermal mode) for T-2 detection. As a proof-of-concept application, this work provides a reference to the design of DSM-LFIA for food safety detection.

Fe-MOF/AuNP-based ratiometric electrochemical immunosensor for the detection of deoxynivalenol in grain products.

Aratiometric assay was designed to improve the sensitivity and reliability of electrochemical immunosensors for deoxynivalenol (DON) detection. The indicator signal caused by the Fe-based metal-organic framework nanocomposites loaded with gold nanoparticles and the internal reference signal from the [Fe(CN)6]3-/4- in the electrolyte came together at the immunosensor. When immunoreactivity occurred, the indicator signals decreased as the concentration of DON increased, while the internal reference signals increased slightly. The ratio of the indicator signal to the internal reference signal was available for reproducible and sensitive monitoring of DON. The prepared immunosensor showed excellent performance in the range from 0.5 to 5000 pg mL-1, and the detection limit was 0.0166 pg mL-1. The immunosensor achieved satisfactory detection toward DON in spiked and actual samples and has a promising application in the control of DON in grain products.

Development of alkaline phosphatase-linked single-chain variable fragment fusion proteins for one-step immunodetection of deoxynivalenol in cereals.

Deoxynivalenol (DON) is a mycotoxin that widely distributes in various foods and seriously threatens food safety. To minimize the consumers' dietary exposure to DON, there is an urgent demand for developing rapid and sensitive detection methods for DON in food. In this study, a bifunctional single-chain variable fragment (scFv) linked alkaline phosphatase (ALP) fusion protein was developed for rapid and sensitive detection of deoxynivalenol (DON). The scFv gene was chemically synthesized and cloned into the expression vector pET25b containing the ALP gene by homologous recombination. The prokaryotic expression, purification, and activity analysis of fusion proteins (scFv-ALP and ALP-scFv) were well characterized and performed. The interactions between scFv and DON were investigated by computer-assisted simulation, which included hydrogen bonds, hydrophobic interactions, and van der Waals forces. The scFv-ALP which showed better bifunctional activity was selected for developing a direct competitive enzyme-linked immunosorbent assay (dc-ELISA) for DON in cereals. The dc-ELISA takes 90 min for one test and exhibits a half inhibitory concentration (IC50) of 11.72 ng/mL, of which the IC50 was 3.08-fold lower than that of the scFv-based dc-ELISA. The developed method showed high selectivity for DON, and good accuracy was obtained from the spike experiments. Furthermore, the detection results of actual cereal samples analyzed by the method correlated well with that determined by high-performance liquid chromatography (R2=0.97165). These results indicated that the scFv-ALP is a promising bifunctional probe for developing the one-step colorimetric immunoassay, providing a new strategy for rapid and sensitive detection of DON in cereals.

Deoxynivalenol Detection beyond the Limit in Wheat Flour Based on the Fluorescence Hyperspectral Imaging Technique.

Deoxynivalenol (DON) is a harmful fungal toxin, and its contamination in wheat flour poses a food safety concern globally. This study proposes the combination of fluorescence hyperspectral imaging (FHSI) and qualitative discrimination methods for the detection of excessive DON content in wheat flour. Wheat flour samples were prepared with varying DON concentrations through the addition of trace amounts of DON using the wet mixing method for fluorescence hyperspectral image collection. SG smoothing and normalization algorithms were applied for original spectra preprocessing. Feature band selection was carried out by applying the successive projection algorithm (SPA), uninformative variable elimination (UVE), competitive adaptive reweighted sampling (CARS), and the random frog algorithm on the fluorescence spectrum. Random forest (RF) and support vector machine (SVM) classification models were utilized to identify wheat flour samples with DON concentrations higher than 1 mg/kg. The results indicate that the SG-CARS-RF and SG-CARS-SVM models showed better performance than other models, achieving the highest recall rate of 98.95% and the highest accuracy of 97.78%, respectively. Additionally, the ROC curves demonstrated higher robustness on the RF algorithm. Deep learning algorithms were also applied to identify the samples that exceeded safety standards, and the convolutional neural network (CNN) model achieved a recognition accuracy rate of 97.78% for the test set. In conclusion, this study demonstrates the feasibility and potential of the FHSI technique in detecting DON infection in wheat flour.

A novel core-shell up-conversion nanoparticles immunochromatographic assay for the detection of deoxynivalenol in cereals

Deoxynivalenol (DON) toxin is a type B group of trichothecene mycotoxins mainly originating from specific Fusarium fungi, seriously harming human and livestock health. Herein, a novel core-shell up-conversion nanoparticles immunochromatographic assay (CS-UCNPs-ICA) was developed for deoxynivalenol based on the competitive reaction principle. By exploiting the fluorescence intensity of the T and C lines of CS-UCNPs-ICA, the concentrations of DON were obtained sensitively and precisely under optimized conditions in 5 min with a detection limit of 0.1 ng/mL. The CS-UCNPs-ICA strips only specifically detect DON and its derivatives (3-Ac-DON and 15-Ac-DON), with no cross-reaction with other mycotoxins. The low CV values illustrated a modest intra- and inter-assay variation, confirming the superior precision of this method. In the spiked experiment, the mean recoveries of corn and wheat ranged from 94.74% to 100.90% and 96.21%–104.81%, respectively. Furthermore, the approach generated results that were in good agreement with data from HPLC and ELISA analyses of naturally contaminated feed and cereals, confirming that the significant advantages of proposed strips were their high practicality, rapidness, and simplicity. Therefore, the CS-UCNPs-ICA strips platform serves as a promising candidate for developing new approaches for rapid testing or high throughput screening from DON in food products.

A ratiomectic aptasensor with enhanced signals based on peroxidase-like enzymes and NH2-MIL-101@MoS2 for trace detection of deoxynivalenol in traditional Chinese herbs

The accumulation of the deoxynivalenol (DON) in the human body poses a significant health risk that is often overlooked, and we urgently need an ultra-sensitive rapid detection platform. Due to the porosity of NH2-MIL-101@MoS2, an increased loading of toluidine blue (TB) serves to create a signal reference. Cobalt@carbon (CoC) derived from metal organic frameworks was combined with NH2-MIL-101(NH2-MIL-101@CoC) to form an enzyme-free Nanoprobe (Apt-pro) with significant catalytic properties. The ratio (IBQ /ITB) was changed by varying the electrochemical signal of benzoquinone (BQ) (IBQ) and the amount of TB deposition (ITB). This aptasensor was successfully applied to detect DON in malt and peach seed, which exhibited a great linear range from 1 fg/mL to 10 ng/mL and low detection limit of 0.31 fg/mL for DON.

AuNPs-BP-MWCNTs-COOH-based electrochemical immunosensor for the determination of deoxynivalenol in wheat flour.

Deoxynivalenol (DON) has drawn considerable attention for its obvious pathogenicity and wide use in agro-products, which cause a potential threat to human health. In this work, an electrochemical immunosensor is developed for the highly sensitive and selective detection of DON in wheat flour using AuNPs-BP-MWCNTs-COOH and antibodies. The AuNPs-BP-MWCNTs-COOH nanocomposite was prepared via an in situ reduction reaction and ultrasonic-assisted liquid-phase exfoliation. The nanocomposite exhibits a larger surface area, decent stability, excellent electron transfer capability, good protein binding capability and prominent specificity. The plentiful carboxyl group on the nanocomposite can bind to the amino group of the antibody, and AuNPs have an affinity for the sulfhydryl group of the antibody, which makes it feasible for the nanocomposite to load the antibody. The peak currents are plotted against the logarithm of DON concentration from 0.002 to 80 ng mL-1 with a limit of detection (LOD) of 0.5 pg mL-1. This approach establishes an effective label-free immunosensor platform for the detection of DON with high sensitivity and selectivity in various food and agricultural products.

Novel Label-Free GelRed-Aptamer Sensor for the Rapid Determination of Deoxynivalenol in Wheat Caused by Fusarium graminearum

Deoxynivalenol (DON) is the key virulence factor in Fusarium head blight. However, rapid and low-cost methods for DON are limited. Herein, a novel label-free GelRed-aptamer sensor was developed for the detection of DON. GelRed was embedded in double strain DNA (dsDNA) consisting of a single chain aptamer and its complementary DNA (cDNA), resulting in the increase of fluorescence intensity. However, DON preferentially combined with the aptamer and did not combine with its cDNA, which would result in the decrease in the formation of the GelRed/aptamer/cDNA complex, greatly reducing the fluorescence intensity. The samples were extracted from wheat, centrifuged, and filtered through a 0.22 μm membrane. Good linearity was obtained for DON from 3.13 to 313 mg L−1. The limit of quantitation (LOQ) for wheat samples was 6.07 mg L−1, providing a low cost method for DON compared with enzyme-linked immunosorbent assays. Experiments with spiked samples showed good recoveries from 92% to 105% with relative standard deviations less than 5.33% with analysis within 20 min. This method is simple and low cost with potential applications in agriculture and food.

Deoxynivalenol (DON)-Triggered Dual-Color Composite Probe Based on Gold Nanoclusters for Simultaneous Imaging of DON and miR-34a in Living Cells.

Deoxynivalenol (DON) is a mycotoxin secreted by Fusarium species, posing great harm to food safety and human health. Therefore, it is of great significance to study its toxic effects and mechanism. miR-34a is a representative biomarker during the process of DON-induced apoptosis. Herein, a DON-triggered dual-color composite probe was constructed for simultaneous imaging of DON and miR-34a in living cells. The aptamer blocks the recognition sequence of miR-34a to realize DON-triggered cell imaging. The specific binding of DON with its aptamer and HCR induced by miR-34a resulted in the recovery of fluorescence of the dual-color Au NCs. Under the optimal conditions, the correlation between the relative fluorescence intensities of dual-color Au NCs showed good linear relationships with the logarithm of DON and miR-34a concentration, respectively. With the increase in DON concentration (0-20 μg/mL) and stimulation time (0-12 h), the fluorescence of dual-color Au NCs gradually recovered. This dual-color Au NCs composite probe can realize simultaneous detection of DON and miR-34a induced by DON, which is significant for verifying the cytotoxic mechanism of DON.