N、S共掺杂碳点的制备及其对Cr^(6+)的检测

以1-亚硝基-2-萘酚-3,6-二磺酸钠和乙二胺为前驱体,采用一步水热法在200℃、8 h的试验条件下制备了蓝色荧光碳点(N,S-CDs)。透射电镜表征所制备N,S-CDs的粒径约为10.31 nm,荧光检测最佳激发和发射波长分别为378和468 nm,荧光量子产率为3.0%。该N,S-CDs对Cr^(6+)具有很好的选择性,基于其与Cr^(6+)之间的内滤效应建立了一种免标记的检测Cr^(6+)的荧光型传感新方法,线性范围为2~100μmol/L和100~330μmol/L,最低检出限为68.23 nmol/L。相较于其他同类检测方法,具有较低的检测限和定量范围。

Controlled Release of Curcumin via Folic Acid Conjugated Magnetic Drug Delivery System

In the paper, folic acid（FA）-mediated and β-cyclodextrin（β-CD） derivatives ftmctionalized magnetic Fe3O4 nanoparticles（MNPs） were successfully prepared as drug carriers for the targeted delivery and controlled release of water-insoluble anticaneer drug. FA-sulfobutyl ether-β-CD-MNPs（FA-SBE-β-CD-MNPs）, FA-hydroxypropyl- β-CD-MNPs（FA-HP-β-CD-MNPs） and FA-carboxymethyl-β-CD-MNPs（FA-CM-β-CD-MNPs） were fabricated, and the loading efficiency and relative entrapment rate of curcumin are 12.04 mg/g, 95.56% for FA-SBE-β-CD-MNPs, 9.6 mg/g, 81.63% for FA-HP-β-CD-MNPs and 7.88 mg/g, 85,28% for FA-CM-β-CD-MNPs, respectively. Meanwhile, at pH：5.0, the optimal release rate of curcumin is about 46.07% for FA-SBE-β-CD-MNPs in 5 h. Cellular uptake in- dicates that curcumin can be selectively transported to targeting site and released from the internalized carriers. The in vitro cytotoxicity reveals that non-toxic FA-SBE-β-CD-MNPs have excellent biocompatibility on HepG2 cells in the tested concentrations. Therefore, FA-SBE-β-CD-MNPs could provide a promising platform for the targeting delivery of water insoluble anti-cancer drugs for different treatment needs of cancer therapy.

Studies on the Interaction Between Vanillin and β-Amyloid Protein via Fluorescence Spectroscopy and Atomic Force Microscopy

β-Amyloid（Afl） plaques and intracellular neurofibrillary lesions in the brain are markers of Alzheimer＇s disease（AD）. The ability to safely decrease Aft concentrations is potentially important as a preventive strategy for AD. The interactions between vanillin and Aft polypeptide were investigated via fluorescence spectroscopy and atomic force microscopy（AFM）. The results of fluorescence and synchronous spectroscopies illustrate that the intrinsic fluorescence of tyrosine（Tyr） residues in Aβ1-42 aggregates can be quenched strongly upon the formation of vanil- lin-Aβ-42 complex. Thioflavine T（ThT）-induced fluorescence changes indicated that Aβ1--42 aggregates could be disaggregated by vanillin, and the AFM images of Aβ1-42 enunciated the depolymerization of Aβ1-42 aggregates by vanillin in a dose-dependent manner. Vanillin may be a potential pharmacological agent for the treatment of AD.