Tools to detect low molecular weight mycotoxin patulin (PAT) are urgently needed because of its harm to human health. Here, we report a simple, effective, and sensitive fluorescent aptasensor based on sulfur quantum dots encapsulated in MOF-5-NH 2 ( [email protected] 2 ) and self-cycling catalyzed hairpin assembly (scCHA) for the detection of PAT in apple juice. The [email protected] 2 synthesized by a “bottle-around-ship” solvothermal method works as a fluorescent probe and offers enhanced fluorescence intensity and good water-solubility versus MOF-5-NH 2 due to the encapsulation of water-soluble SQDs . Meanwhile, the scCHA designed by the two DNA hairpins is initiated after the formation of PAT/aptamer, which further recycles PAT to effectively capture multiple fluorescence probes ( [email protected] 2 ) and amplify the detection signal. Attributed to the synergistic effect between the strong fluorescence intensity of [email protected] 2 and the efficient PAT utilization of scCHA, the fluorescent aptasensor exhibits high sensitivity with detection limits as low as 0.753 pg/mL. The system has satisfactory specificity, anti-interference, and reproducibility (RSDs of intra-assay and inter-assay were 3.24% and 8.60%, respectively). The recoveries in apple juice were between 89.03% and 107.67%, which were with good consistency versus high-performance liquid chromatography (HPLC). These data collectively show that the developed fluorescent aptasensor has a good practical application value.
Shanshan Ma,Jie Fei,Jifeng Yan,Longqi Liu,Qiyue Huang,Man Zhou,Hejun Li
The limitation in the poor interface would severely affect the further development and application of carbon fiber reinforced composites (CFRP). Unique organic–inorganic hybrid architectures of MOF-5-NH 2 and carboxymethyl cellulose (CMC) were established on the fiber/matrix interphase for promoting mechanical and tribological performances of the composites. The existence of above interfacial reinforced structure was in favor of generating abundant micromechanical interaction sites for enhancing mechanical interlocking. Meanwhile, high-density chemical crosslinking networks played a positive role in elevating interfacial adhesion, further relieving stress concentration and hindering crack propagation. The tensile strength of CFRP-2, CFRP-3, CFRP-4, and CFRP-5 exhibited a significant rising of 27.18%, 30.64%, 27.75%, and 36.88%, respectively. The friction coefficient of MOF-5-NH 2 /CMC modified sample increased from 0.0953 to 0.1219, while the drop in the wear rate of the composites achieved 68.51%. This work provides an effective method for achieving the structure–function integrated design of composite materials according to the organic–inorganic interface enhancement of MOF-5-NH 2 /CMC.
危险品化学品经营许可证（带存储）