Applying hollow octahedron PtNPs/Pd-CuO nanozyme and highly conductive AuPtNPs/Ni-Co NCs to colorimetric -electrochemical dual-mode aptasensor for AFB1 detection.

Background: Aflatoxin B1 (AFB1) is a secondary metabolite produced by Aspergillus flavus and Aspergillus parasiticus. This toxin is highly carcinogenic and toxic, posing a serious threat to human and animal health. AFB1 primarily enters the human body through contaminated food, particularly peanuts, corn, nuts, and wheat.

An aptasensor consisting of the integrated MOF-derived Zn-MOF-on-Co-MOF coupled with AuNPs nanocomposites and aptamer for ultrasensitive assay of fipronil.

The conductivity of Zn-MOF-on-Co-MOF synthesized by one-pot method is improved by searching for the optimum carbonization temperature, which overcomes the limitation of traditional MOF. In order to further enhance electron transfer, the mesoporous PtPdCo trimetal was introduced, which provided considerable load capacity for methylene blue (MB) and reverse complementary DNA (sDNA), and also showed excellent catalytic activity for MB. In this study, the conductivity of aptasensor was improved by modifying carbonized MOF as the base material.

Plant-based protein amyloid fibrils: Origins, formation, extraction, applications, and safety.

Amyloid fibrils (AFs) are highly ordered nanostructures formed through the self-assembly of proteins under specific conditions. Due to their unique properties, AFs have garnered significant attention as biomaterials over the past decade. Nevertheless, the increasing reliance on animal proteins for AFs production raises sustainability concerns, highlighting the need for a transition to plant-based proteins as more environmentally friendly feedstocks.

Selective aptasensor of deoxynivalenol based on dual signal enhancement of thionine electrochemistry using silver nanoparticle-loaded label at gold nanoparticle-loaded electrodes.

In this work, an efficient sensing platform deoxynivalenol (DON) detection was constructed through monitoring the current change of a competitive mechanism triggered by DON, leading the signal label detached from the electrode surface by square-wave voltammetry using thionine (Thi) as a redox indicator. The complementary strand of aptamer (cDNA) and Thi were loaded onto Fe/Ni bimetallic metal-organic framework loaded with sliver nanoparticles (AgNPs@FeNi-MOF) to construct AgNPs@FeNi-MOF/cDNA/Thi signal probes. In the presence of DON, the aptamer sequence was more predisposed to form an aptamer-DON complex, resulting in the displacement of the cDNA.

Detection of AFB by Immunochromatographic Test Strips Based on Double-Probe Signal Amplification with Nanobody and Biotin-Streptavidin System.

Aflatoxin B (AFB) is highly toxic and difficult to prevent. It is mainly produced by fungi and exists in plants and animals and is classified by the World Health Organization as a class I carcinogen, posing a serious threat to human and animal health. Therefore, it is important to establish an efficient, sensitive, and on-site detection method for AFB to protect human health.

A bifunctional MXene@PtPd NPs cascade DNAzyme-mediated fluorescence/colorimetric dual-mode biosensor for Pb determination.

Pb has numerous sources in cosmetics, industrial pollution and other environments. Therefore, sensitive and accurate detection of Pb content is extremely important in food safety. In this work, bifunctional nanomaterials TiC@PtPd NPs with fluorescence quenching effect and peroxidase activity were prepared by in situ growth of platinum‑palladium nanoparticles (PtPd NPs) on the surface of 2D material TiC.

An aptasensor with colorimetric and electrochemical dual-outputs for malathion detection utilizing peroxidase-like activity of Fe-MOF.

An aptasensor with dual-outputs was developed for malathion detection. Fe-MOF was synthesized to design favorable signal probes for catalytic amplification. Owing to the excellent peroxidase-like activity of Fe-MOF, the redox reaction was catalyzed to produce the dual-outputs of colorimetric and electrochemical.

Label-free ratiometric fluorescence detection of Pb structure-specific fluorescent dyes and dual signal amplification.

Lead ions (Pb) are a widely distributed and highly toxic heavy metal pollutant, which seriously threatens the environment, economy and human safety. Here, a label-free ratiometric fluorescent biosensor was constructed for Pb detection using DNAzyme-driven target cycling and exonuclease III (Exo III)-mediated DNA cycling as a dual signal amplification strategy. The SYBR Green I (SGI) and -methyl mesoporphyrin IX (NMM) used in this study are characterized by low cost, storage resistance, and short preparation time compared with conventional signaling probes labeled with fluorescent groups.

Triple-helix molecular-switch-actuated rolling circle amplification and catalytic hairpin assembly multistage signal amplified fluorescent aptasensor for detection of aflatoxin B1.

Background: Mycotoxins, a class of secondary metabolites produced by molds, are widely distributed in nature and are very common in food contamination. Aflatoxin B1 (AFB1) is a highly stable natural mycotoxin, and many agricultural products are easily contaminated by AFB1, it is important to establish a sensitive and efficient AFB1 detection method for food safety. The fluorescence aptamer sensor has shown satisfactory performance in AFB1 detection, but most of the fluorescence aptasensors are not sensitive enough, so improving the sensitivity of the aptasensor becomes the focus of this work.

Functional black phosphorus-based sensors for food safety applications: A review.

Food safety has garnered global attention, necessitating advanced methods for the quick and accurate detection of contaminants. Sensors, notable for their ease of use, high sensitivity, and fast analysis, are prominent. Two-dimensional (2D) nanomaterials have been employed to improve sensor performance.

A dual-signal mode electrochemical aptasensor based on tetrahedral DNA nanostructures for sensitive detection of citrinin in food using PtPdCo mesoporous nanozymes.

Citrinin (CIT) is a mycotoxin with nephrotoxicity and hepatotoxicity, presenting a significant threat to human health that is often overlooked. Therefore, a dual-signal mode (DPV and SWV) aptasensor for citrinin (CIT) detection was constructed based on tetrahedral DNA nanostructures (TDN) in this study. Furthermore, PtPdCo mesoporous nanozymes exhibit catalase-like catalytic functions, generating significant electrochemical signals through a Fenton-like reaction.

Electrochemical aptamer sensor based on AgNPs@PDANSs and "sandwich" structure guidance for the detection of tobramycin in water samples.

In this study, an ultrasensitive detection platform for tobramycin (TOB) was developed, featuring a "sandwich" structure guided by AgNCs@PDANSs and Thi-AuNCs@ZnONSs. To address the issue of large background current peak signals in tagless sensors, Thi-AuNCs@ZnONSs composites were synthesized as signal tags. Zinc oxide nanosheets (ZnONSs) served as the loading agent, and AuNCs with the electroactive molecule Thi acted as carriers.

[Simultaneous determination of 21 perfluorinated and polyfluoroalkyl substances in plant oils by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry].

Edible plant oils are a key component of the daily human diet, and the quality and safety of plant oils are related to human health. Perfluorinated and polyfluoroalkyl substances (PFASs) are pollutants that can contaminate plant oil through the processing of raw materials or exposure to materials containing these substances. Thus, establishing a sensitive and accurate analytical method for the determination of PFASs is critical for ensuring the safety of plant oils.

Simultaneous Determination of Aflatoxin B1 and Ochratoxin A in Cereals by a Novel Electrochemical Aptasensor Using Metal-Organic Framework as Signal Carrier.

A novel electrochemical aptasensor was prepared for the simultaneous determination of aflatoxin B1 (AFB1) and ochratoxin A (OTA). Composites of Au nanoparticles and polyethyleneimine-reduced graphene oxide (AuNPs/PEI-RGO) with good electrical conductivity and high specific surface area were employed as the supporting substrate, demonstrating the ability to provide more binding sites for aptamers and accelerate the electron transfer. Aptamers were immobilized on a AuNPs/PEI-RGO surface to specifically recognize AFB1 and OTA.

Simultaneous Hg and Pb detection in water samples using an electrochemical aptasensor with dual signal amplification by exonuclease III and metal-organic frameworks.

Heavy metal pollution in the environment has become a significant global concern due to its detrimental effects on human health and the environment. In this study, we report an electrochemical aptasensor for the simultaneous detection of Hg and Pb. Gold nanoflower/polyethyleneimine-reduced graphene oxide (AuNFs/PEI-rGO) was introduced on the surface of a gold electrode to improve sensing performance.

Nanobody and CuS Nanoflower-Au-Based Lateral Flow Immunoassay Strip to Enhance the Detection of Aflatoxin B.

In the realm of analysis, the lateral flow immunoassay (LFIA) is frequently utilized due to its capability to be fast and immediate. However, the biggest challenge of the LFIA is its low detection sensitivity and tolerance to matrix interference, making it impossible to enable accurate, qualitative analyses. In this study, we developed a new LFIA with higher affinity and sensitivity, based on a nanobody (G8-DIG) and CuS nanoflowers-Au (CuS NFs-Au), for the detection of aflatoxin B (AFB) in maize.

Ultrasensitive label-free electrochemical aptasensor for Pb detection exploiting Exo III amplification and AgPt/GO nanocomposite-enhanced transduction.

Lead ion pollution has become a serious public health concern worldwide. Therefore, sensitive detection of Pb is critical to control lead pollution, assess risks, and safeguard the health of vulnerable populations. This study reports a highly sensitive labelling-free electrochemical aptasensor for Pb detection.

A novel electrochemical aptasensor based on AgPdNPs/PEI-GO and hollow nanobox-like Pt@Ni-CoHNBs for procymidone detection.

Herein, an aptasensor based on a signal amplification strategy was developed for the sensitive detection of procymidone (PCM). AgPd nanoparticles/Polenimine Graphite oxide (AgPdNPs/PEI-GO) was weaned as electrode modification material to facilitate electron transport and increase the active sites on the electrode surface. Besides, Pt@Ni-Co nanoboxes (Pt@Ni-CoHNBs) were utilized to be carriers for signaling tags, after hollowing ZIF-67 and growing Pt, the resulting Pt@Ni-CoHNBs has a tremendous amounts of folds occurred on the surface, enables it to carry a larger quantity of thionine, thus amplify the detectable electrochemical signal.

Amyloid-like Aggregation of Wheat Gluten and Its Components during Cooking: Mechanisms and Structural Characterization.

Amyloid-like aggregation widely occurs during the processing and production of natural proteins, with evidence indicating its presence following the thermal processing of wheat gluten. However, significant gaps remain in understanding the underlying fibrillation mechanisms and structural polymorphisms. In this study, the amyloid-like aggregation behavior of wheat gluten and its components (glutenin and gliadin) during cooking was systematically analyzed through physicochemical assessment and structural characterization.

"Two-in-One" PtPdCu Trimetallic Multifunctional Nanoparticles-Mediated Dual-Signal-Integrated Aptasensor for Ultradetection of Enrofloxacin.

Balancing the accuracy and simplicity of aptasensors is a challenge in their construction. This study addresses this issue by leveraging the remarkable loading capacity and peroxidase-like catalytic activity of PtPdCu trimetallic nanoparticles, which reduces the reliance on precious metals. A dual-signal readout aptasensor for enrofloxacin (ENR) detection is designed, incorporating DNA dynamic network cascade reactions to further amplify the output signal.

A fluorescence-electrochemical dual-mode aptasensor based on novel DNA-dependent PBNFs@PtPd for highly selective and sensitive detection of procymidone through hybridization chain reaction.

Herein, a study for the first application of a hybridization chain reaction, a 1,8-naphthalimides-DNA (NDs) intercalator, and DNA-dependent Prussian blue nanoflowers@PtPd materials (PBNFs@PtPd) in the development of a fluorescence-electrochemical (FL-EC) aptasensor. This construction establishes an efficient sensing platform for the detection of procymidone (PCM). In the context of the described experiment, dual-mode detection is achieved through the generation of FL signals by an aptamer labeled with a Cy5 moiety and the formation of DPV signals by the modification of a thionine-appended 1,8-naphthalimide (Thi-NDs).

Effects of sanxan on water and ice crystal status of salt free frozen cooked noodles during freeze-thaw cycles.

This study compared four biocolloids (sanxan, xanthan gum, curdlan, and guar gum) in different concentrations to replace NaCl in improving the recooking quality of salt free frozen cooked noodles (SF-FCNs). Sanxan outperformed NaCl and other biocolloids significantly improving the firmness (21.0%), chewiness (63.

Effect of sanxan on the composition and structure properties of gluten in salt-free frozen-cooked noodles during freeze-thaw cycles.

In this study, the mechanisms by which sanxan protected the quality of salt-free frozen-cooked noodles (SFFCNs) were investigated, with a focus on the composition and structural properties of gluten. The results showed that sanxan facilitated the formation of glutenin macropolymer and maintained the stabilization of glutenin subunits in freeze-thaw cycles (FTs). In terms of protein structure, sanxan weakened the disruption of secondary structure caused by FTs and increased the proportion of --gauche (g-g-g) conformations in the disulfide (S-S) bonds bridge conformation.

Mn-Triggered Swing-Arm Robot Strategy Using Anemone-Like Thi@AuPd@Cu-MOFs as Signaling Probes for the Detection of T-2 Toxin.

Herein, we synthesized anemone-like copper-based metal-organic frameworks (MOFs) loaded with gold-palladium nanoparticles (AuPd@Cu-MOFs) and polyethylenimine-reduced graphene oxide/gold-silver nanosheet composites (PEI-rGO/AuAg NSs) for the first time to construct the sensor and to detect T-2 toxin (T-2) using triple helix molecular switch (THMS) and signal amplification by swing-arm robot. The aptasensor used PEI-rGO/hexagonal AuAg NSs as the electrode modification materials and anemone-like AuPd@Cu-MOFs as the signal materials. The prepared PEI-rGO/hexagonal AuAg NSs had a large specific surface area, excellent electrical conductivity, and good stability, which successfully improved the electrochemical performance of the sensors.