采用机械共混法制备了Si O2改性的CPVC/PVDF/PMMA复合材料,考察了Si O2用量、PVB、PVC、丁腈粉、DBP对材料成膜性能、吸墨性能、柔软性和韧性的影响.结果表明:1当Si O2的质量浓度为4.5%时,CPVC的成膜性和吸墨性能最佳;2当DBP、丁腈粉的质量分数分别为3.0%和3.4%时,膜的柔韧性最佳;3最佳的制备工艺是将PMMA、CPVC、PVDF和丁腈粉溶于DMAC和DBP的混合溶液中,再恒温4 h.
The interaction between baicalein and amyloid-β（Aβ） polypeptide was investigated by fluorescence and UV-Vis absorbance spectroscopy. The absence of the characteristic peak of tyrosinate（Tyr） in the absorption spectra of Afl-baicalein complexes provided evidence that the sole Tyr residue in Aβis not bound to baicalein, but remains close to it. The intrinsic fluorescence of Tyr residues in Aβ1-42 aggregates was quenched strongly by the excited-state ionization of baicalein. In this complex the hydroxyl group was not ionized, but to ionize immediately upon excitation. Absorbance, fluorescence and synchronous spectroscopies show that the formation of Schiff base between the quinone of baicalein and the lysine（Lys） side chains ofAβ1-42 is another major reason in the depolymerization of Aβ1-42 aggregates by baicalein. It is desirable that our research would offer some valuable reference for the application of flavonoid derivants in Alzheimer＇s disease（AD） treatment.
SONG Sheng-meiWANG Yong-xiangXIONG Li-minQU Ling-boXU Mao-tian
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.
SONG ShengmeiLI MingluGONG XiaojuanHAN HuiZHOU YehongWANG LiSHUANG ShaominDONG Chuan
