A series of polyvinylpyrrolidone-stabilized heteropolyacids(PVP-HPAs)are generated by self-assembly of HPAs and PVP in methanol.The PVP-HPAs are then employed as catalysts for the synthesis of poly(oxymethylene)dimeth...A series of polyvinylpyrrolidone-stabilized heteropolyacids(PVP-HPAs)are generated by self-assembly of HPAs and PVP in methanol.The PVP-HPAs are then employed as catalysts for the synthesis of poly(oxymethylene)dimethyl ethers(DMMn,n1)by the methanolysis of trioxane.The results suggest that the acidity of PVP-HPAs is tunable by changing the ratio of PVP and HPAs,which is a key factor for the selectivity of the DMMn product.By optimizing the composition and reaction conditions,two types of PVP-HPA,PVP-phosphotungstic acid(PVP-HPW)in a PVP/HPW ratio of 1/4:1 and PVP-silicotungstic acid(PVP-HSi W)in a PVP/HSi W ratio of 1/4:3/4,respectively afford 52.4%and 50.3%yields of DMM2–5.The optimized catalysts are reusable for a minimum of 10 times without a significant drop in performance.展开更多
A combinational therapeutic system that simultaneously administrates various pathways is preferred for anti-cancer treatment.In the present study,we successfully constructed a co-delivery system,multivesicular liposom...A combinational therapeutic system that simultaneously administrates various pathways is preferred for anti-cancer treatment.In the present study,we successfully constructed a co-delivery system,multivesicular liposomes(MVLs)co-encapsulating doxorubicin(DOX)and luminespib(AUY922).A simple and accurate dual-wavelength spectrophotometric method was established for the determination of DOX and AUY922 in liposomal formulation.MVL-loading drugs were prepared by a multi-emulsion solvent evaporation method,which exhibited excellent physicochemical properties,such as particle size of 3–8μm and high entrapment efficiency above 95%for DOX and 73%for AUY922.The synergetic cytotoxic effect for these two drugs was evaluated in MDA-MB-231 cells.The in vitro antitumor studies demonstrated the superior anti-proliferation activity of DOX and AUY922 with a combination index of 0.43,indicating a great synergistic effect.The experimental data suggested that combinational use of DOX and AUY922 within liposomes could be an effective way to develop efficient treatments of cancers.展开更多
基金financially supported by the National Basic Research Program of China(2011CBA00508)the National Natural Science Foundation of China(21173175,21303141)+1 种基金the Research Fund for the Doctoral Program of Higher Education(20110121130002)the Program for Changjiang Scholars and Innovative Research Team in University(IRT1036)
文摘A series of polyvinylpyrrolidone-stabilized heteropolyacids(PVP-HPAs)are generated by self-assembly of HPAs and PVP in methanol.The PVP-HPAs are then employed as catalysts for the synthesis of poly(oxymethylene)dimethyl ethers(DMMn,n1)by the methanolysis of trioxane.The results suggest that the acidity of PVP-HPAs is tunable by changing the ratio of PVP and HPAs,which is a key factor for the selectivity of the DMMn product.By optimizing the composition and reaction conditions,two types of PVP-HPA,PVP-phosphotungstic acid(PVP-HPW)in a PVP/HPW ratio of 1/4:1 and PVP-silicotungstic acid(PVP-HSi W)in a PVP/HSi W ratio of 1/4:3/4,respectively afford 52.4%and 50.3%yields of DMM2–5.The optimized catalysts are reusable for a minimum of 10 times without a significant drop in performance.
基金School of Pharmaceutical Sciences,Peking University Health Science Center,Beijing 100191,China。
文摘A combinational therapeutic system that simultaneously administrates various pathways is preferred for anti-cancer treatment.In the present study,we successfully constructed a co-delivery system,multivesicular liposomes(MVLs)co-encapsulating doxorubicin(DOX)and luminespib(AUY922).A simple and accurate dual-wavelength spectrophotometric method was established for the determination of DOX and AUY922 in liposomal formulation.MVL-loading drugs were prepared by a multi-emulsion solvent evaporation method,which exhibited excellent physicochemical properties,such as particle size of 3–8μm and high entrapment efficiency above 95%for DOX and 73%for AUY922.The synergetic cytotoxic effect for these two drugs was evaluated in MDA-MB-231 cells.The in vitro antitumor studies demonstrated the superior anti-proliferation activity of DOX and AUY922 with a combination index of 0.43,indicating a great synergistic effect.The experimental data suggested that combinational use of DOX and AUY922 within liposomes could be an effective way to develop efficient treatments of cancers.