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A fluorescent aptasensor was constructed for the high-sensitivity and high-selectivity detection of 17β-estradiol (E2) based on the fluorescence quenching effect of gold nanoparticles (AuNPs) on carbon quantum dots (CQDs) and the specific affinity of aptamers to targets. Under the optimal conditions (particle size of AuNPs = 39 nm, AuNPs amount = 200 μL, quenching time = 20 min, and fluorescence recovery time = 60 min), a good linear relationship was observed between the fluorescence recovery degree (y) of the sensor and the logarithmic value (x) of E2 concentration (2 × 10-5–2 × 10-9 mol/L), which was fitted with the following equation: y = 58.50x + 558.95 with a determination coefficient (R2) of 0.992. The detection of limit (LOD) of E2 was 3.4 × 10-10 mol/L. Finally, the aptasensor was successfully applied to the detection of E2 spiked in milk and environmental water samples with good recoveries of 89.67%‒113.36%, suggesting the potential for practical application.

A core-shell-satellite nanostructure surface-enhanced Raman scattering (SERS) substrate based on magnetic nanoparticles, metal-organic frameworks (MOFs) and gold nanoparticles (Ag NPs) was established and applied in the simple, rapid and sensitive detection of the organophosphorus pesticide triazophos in agricultural products. MIL-100(Fe)-coated Fe3O4 was prepared by low-temperature cyclic self-assembly method, and Ag NPs were in-situ grown on the surface of MIL-100(Fe)-coated Fe3O4 by silver mirror cycling. The SERS sensing of triazophos residues in apples was carried out. The logarithmic value (Y) of the characteristic peak intensity of triazophos was linearly related to the logarithmic value (X) of its concentration in the range of 0.05–10 mg/L, which was described by the following equation: Y = 0.573 8X + 2.804 (R2 = 0.980). The limit of detection (LOD) was as low as 11.9 mg/L. The recoveries of the developed method ranged from 90.07% to 103.27% at spiked concentrations of 2, 5, and 10 mg/L. Therefore, the prepared SERS substrate has great potential for application in the detection of pesticide residues in foods.

Background: Hypoxia is often involved in tumor microenvironment, and the hypoxia‐induced signaling pathways play a key role in aggressive cancer phenotypes, including angiogenesis, immune evasion, and therapy resistance. However, it is unknown what role genetic variants in the hypoxia‐related genes play in survival of patients with non‐small cell lung cancer (NSCLC). Methods: We evaluated the associations between 16,092 single‐nucleotide polymorphisms (SNPs) in 182 hypoxia‐related genes and survival outcomes of NSCLC patients. Data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial were used as the discovery dataset, and the Harvard Lung Cancer Susceptibility (HLCS) Study served as the replication dataset. We also performed additional linkage disequilibrium analysis and a stepwise multivariable Cox proportional hazards regression analysis in the PLCO dataset. Results: An independent SNP, ERRFI1 rs28624 A > C, was identified with an adjusted hazards ratio (HR) of 1.31 (95% CI = 1.14–1.51, p = 0.0001) for overall survival (OS). In further analyses, unfavorable genotypes AC and CC, compared with the AA genotype, were associated a worse OS (HR = 1.20, 95% CI = 1.03–1.39, p = 0.014) and disease‐specific survival (HR = 1.21, 95% CI = 1.04–1.42, p = 0.016). Further expression quantitative trait loci analysis indicated that ERRFI1 rs28624C genotypes were significantly associated with higher ERRFI1 mRNA expression levels in the whole blood. Additional analysis showed that high ERRFI1 mRNA expression levels were associated with a worse OS in patients with lung adenocarcinoma. Conclusion: Our findings suggest that genetic variants in the hypoxia‐related gene ERRFI1 may modulate NSCLC survival, potentially through their effect on the gene expression. [ABSTRACT FROM AUTHOR]

Disulfidptosis is a novel form of programmed cell death involved in migration and invasion of cancer cells, but few studies investigated the roles of genetic variants in disulfidptosis-related genes in survival of patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). We used Cox proportional hazards regression analyses, Kaplan–Meier curves and receiver operating characteristic curves to assess effects of genetic variants in 14 disulfidptosis-related genes on overall survival of 866 HBV-HCC patients. The Bayesian false discovery probability was used for multiple testing corrections. We also investigated biological mechanisms of the significant variants through expression quantitative trait loci analyses using the data from publicly available databases, luciferase reporter assays and differential expression analyses. As a result, we identified two independently functional single nucleotide polymorphisms (SNPs) (INF2 rs4072285 G > A and INF2 rs4444271 A > T) that predicted overall survival of HBV-HCC patients, with adjusted hazard ratios of 1.60 (95% CI = 1.22–2.11, P  = 0.001) and 1.50 (95% CI = 1.80–1.90, P  < 0.001), respectively, after multiple testing correction. Luciferase reporter assays indicated that both INF2 rs4072285 A and INF2 rs4444271 T alleles increased INF2 mRNA expression levels (P  < 0.001) that were also higher in HCC tumor tissues than in adjacent normal tissues (P  < 0.001); such elevated INF2 expression levels were associated with a poorer survival of HBV-HCC patients (P  < 0.001) in the TCGA database. In summary, this study supported that INF2 rs4072285 and INF2 rs4444271 may be novel biomarkers for survival of HBV-HCC patients. [ABSTRACT FROM AUTHOR]

Objective: The development of a method for detecting pesticide residues based on surface enhanced Raman scattering (SERS) substrate of MXenes (Ti3C2Tx) of two-dimensional nanoparticle materials. Methods: Firstly, a single layer of negatively charged MXenes two-dimensional material was prepared by fluorine salt etching method, and then synthesized 30 nm of gold nanoparticles (AuNPs) modified by the positively charged surfactant CTAC, and AuNPs/MX- enes was prepared with MXenes loaded with AuNPs by electrostatic adsorption. Secondly, the concentration ratio of AuNPs and MXenes colloidal solutions was optimized with R6G as the Raman probe molecule. Thirdly, it is used for the detection of thiram. Results: The Raman enhancing factor of AuNPs/MXenes is 1.7xl05, which showed good SERS activity. A linear relationship was constructed between the strength of the thiram Raman characteristic peak at 1 379 cm-1 and the logarithm of the thiram pesticide residue concentration, and the standard curve was obtained: y=888x+l 151, the coefficient R2 was 0.986, and the detection limit was 0.051 ng/mL, which was lower than the national standard of 5 ng/mL. The QuEChERS method was used to pretreat the citrus samples, and the SERS detection of thiram residue in the real citrus samples was realized, and the recovery rate ranged from 101.1% to 122.0%. Conclusion: The SERS substrate prepared based on the MXenes structure has potential for thiram detection in citrus samples. [ABSTRACT FROM AUTHOR]

Aquaculture fungicide causes threats to the human community and their sensitive detection are thus essential for food safety. Herein, MoS2/g-C3N4@Au heterojunction-based recyclable SERS substrate was developed for fungicide detection. The optimal substrate exhibited good SERS performance with a detection limit as low as 9.908 × 10−5 mg L−1 for malachite green (MG). Furthermore, an MCN@Au-based photodegradation of crystal violet (CV) under simulated light irradiation was realized, resulting in a degradation rate of 95.6%. With the dual function of the as-synthesized materials, good reusability of the substrates for at least six "detection-degradation" cycles was achieved. In addition, the MG in prawn extract could be sensitively determined with a satisfactory recovery from 91.60 to 124.00%. This work paves an avenue for the fabrication of heterojunction-based recyclable SERS substrates and provides a novel weapon for food safety protection. [ABSTRACT FROM AUTHOR]

Dimethoate contaminants in food pose a threat to human health. Rapid and sensitive trace detection methods are required to keep food safe. In this study, a novel fluorescent aptasensor was developed for the sensitive detection of dimethoate based on carbon quantum dots labeled with double-stranded DNA (CQDs−apt−cDNA) and Ti3C2Tx flakes. Under optimal conditions, the aptasensor showed a good linear range of 1 × 10−9 to 5 × 10−5 M for dimethoate with a coefficient of determination (R2) of 0.996. Besides, a low detection limit of 2.18 × 10−10 M was obtained. The aptasensor showed high selectivity in interference samples and good reproducibility with an RSD of 3.06% (<5%) for dimethoate detection. Furthermore, the proposed aptasensor was applied to the detection of dimethoate in apple juice and tap water with satisfactory recoveries from 96.2 to 104.4%. Because of these benefits, this aptasensor has the potential and promise for detecting food contaminants in the food industry. [ABSTRACT FROM AUTHOR]