A light-responsive material, aminoazobenzene functionalized AlMCM-41, was synthesized and characterized in order to be used as carrier for drug delivery devices. The light-induced hydrophobic-hydrophilic switching effect of azobenzene functionalized aluminosilicate was exploited in the release of irinotecan, a cytostatic drug. To obtain the functionalized mesoporous support, an azobenzene-silane precursor was synthesized by coupling 4-(4′-aminophenylazo) benzoic acid with 3-aminopropyl triethoxysilane and further grafted on AlMCM-41. The azobenzene functionalized mesoporous aluminosilicate exhibited no significant toxicity towards murine fibroblast healthy cells and a reduced toxicity towards murine melanocyte cells. The hybrid materials obtained by loading irinotecan on AlMCM-41 (wt. 35.4%) and aminoazobenzene modified AlMCM-41 (wt. 22%), respectively were characterized by FTIR, small and wide angle XRD, N2 adsorption-desorption isotherms and DSC analyses. A two-fold increase in the drug release rate from azobenzene functionalized aluminosilicate in phosphate buffer solution under UV irradiation was noticed, as compared with dark conditions. Moreover, the azobenzene functionalization of AlMCM-41 significantly increased the irinotecan delivery rate and total cumulative release in comparison with the pristine AlMCM-41 in similar conditions.
Demand for large pore size molecular sieves has given rise to great interests in a new family of silica-based mesoporous materials designated as M41s, which expand typical molecular sieves into an extra-large pore range and generate the potential for the applications of these materials in catalysis and sorption for very bulky molecules1-6. MCM-41 possesses a hexagonal arrangement of uniform mesopore ranging from 15 to 100 ? and can be prepared with varied Si/Al ratios. The investigations of … 相似文献
Selective catalytic reduction of nitrogen monoxide with propene over two kinds of CuCl/MCM-41 catalysts prepared by a dispersion
method has been studied. It was found that CuCl/AlMCM-41 exhibits substantially higher activity over CuCl/SiMCM-41. Characterization
of these samples by H2-TPR, IR and XRD showed that the active copper species were mainly related to Cu2+ and Cu+ ions in CuCl/AlMCM-41 catalyst. 相似文献
A series of AlMCM-41 molecular sieves was synthesized starting from a hydrogel with the following molar composition: 1CTMABr:4.58SiO2:(0.437 + X)Na2O:XAl2O3:200H2O. Tetramethylammonium silicate (TMAS) was used as silicon source and cethyltrimethylammonium bromide (CTMABr) was used as structure template. The obtained materials were characterized by nitrogen adsorption, XRD, FT-IR and TG/DTG. Model-free kinetic algorithms were applied in order to determinate conversion, isoconversion and apparent activation energy to decomposition of CTMA+ species from the AlMCM-41 materials with different silicon/aluminium (Si/Al) ratios of 20, 40, 60 and 80. 相似文献
Silver sulfide (Ag2S) clusters were synthesized in microporous zeolites and mesoporous AlMCM-41 by the sulfurization of Ag+ ions exchanged within the pores of the host. Characterization was performed by means of XRD, UV-Vis Ag K-edge XAFS and photoluminescence. The pore size of the host has great effects on the photoluminescence properties. Ag2S/AlMCM-41 showed photoluminescence at the longer wavelengths than Ag2S/zeolites. The photoluminescence band of Ag2S in the zeolite with 1-dimensional channels was narrow in comparison to the Ag2S in zeolites with 2- or 3-dimensional channels. 相似文献