The objective of this work is to construct a nanosuspension drug delivery system of probucol,a BCS II drug,in order to improve its dissolution and oral bioavailability.The wet milling procedure using planetary beads-m...The objective of this work is to construct a nanosuspension drug delivery system of probucol,a BCS II drug,in order to improve its dissolution and oral bioavailability.The wet milling procedure using planetary beads-milling equipment was utilized to grind the raw probucol to ultrafine nanoparticle/nanocrystal aqueous suspension that was further solidified by freeze-drying process.Cellulose derivatives of different substitution groups and molecular weights,including HPMC,HPC,and MC,were evaluated as the primary stabilizer of probucol nanosuspension.Ternary stabilizers system composed of a primary stabilizer(cellulose derivative,i.e.HPC),a nonionic surfactant(Pluronic R F68),and an anionic surfactant(SDS)was employed to obtain probucol nanosuspension of finer particle size and enhanced dissolution in aqueous media.The probucol nanosuspension with good physical stability showed no obvious change of particle size even after storing over 7 d at 4°C or 25°C.The solidified probucol nanosuspension with trehalose as the cryoprotectant showed the highest dissolution rate(>60%at 2 h)compared to other cryoprotectant.The in vivo pharmacokinetic evaluation indicated about 15-folds higher AUC value of the probucol nanosuspension compared to that of coarse probucol suspension after oral administration to rats.The probucol nanosuspension prepared by wet-milling and ternary stabilizers system may find wide applications for improving the dissolution and oral absorption of water-insoluble drugs.展开更多
Mg_(1-X)Cu_XFe_2O_4 type spinel ferrite was prepared by solid reaction method in order to discuss the heat generation ability in AC magnetic field.The cubic type ferrite structure was obtained for X=0-0.6 samples calc...Mg_(1-X)Cu_XFe_2O_4 type spinel ferrite was prepared by solid reaction method in order to discuss the heat generation ability in AC magnetic field.The cubic type ferrite structure was obtained for X=0-0.6 samples calcined at 1200℃,and the mixture phase of cubic and tetragonal structures were obtained for X=0.7,0.8 samples from XRD result. The highest lattice parameter and highest hysteresis loss value were also shown at X=0.6 sample,the crystal distortion was increased with increase the Cu^(2+)substitution in cubic type ferrite structure.The sized nano Mg_(0.4)Cu_(0.6)Fe_2O_4 powder was prepared by physical milling method using beads milling.The highest heat generation in the AC magnetic field was obtained for the 6 h milled samples using 0.1mm beads.The Cu^(2+)substitution for MgFe_2O_4 ferrite and the beads milling were very effective for the improvement of their heat generation ability in AC magnetic field.展开更多
黑果花楸是一种具有很高营养价值和药用价值的小浆果树种,其果实中富含的多酚物质更是具有抗心血管病、抗肿瘤、抗氧化等生理活性,具有很高的开发价值。为了更好的开发利用黑果花楸,本研究以产自俄罗斯的黑果花楸果实为材料,采用珠磨法...黑果花楸是一种具有很高营养价值和药用价值的小浆果树种,其果实中富含的多酚物质更是具有抗心血管病、抗肿瘤、抗氧化等生理活性,具有很高的开发价值。为了更好的开发利用黑果花楸,本研究以产自俄罗斯的黑果花楸果实为材料,采用珠磨法提取其体内的多酚物质,以多酚得率为指标设计6组单因素试验,根据6组单因素试验结果选取对多酚得率影响最大的3个因素,响应面法优化提取条件,最终得到最佳提取条件为:液料比为63.20 m L/g,时间为2.11h,珠填充量为61.65%,在此条件下,多酚得率理论上为27.29 mg/g,对其进行验证试验结果多酚得率为27.27 mg/g,误差为0.02%,证明试验结果可靠。本研究为黑果花楸果实多酚的提取工艺提供了参考,为黑果花楸的进一步开发利用提供了新思路及理论依据。展开更多
A comparative evaluation of three different cell-disruption methods for the release of hydrogenase from H2 -producing bacterium E. harbinenase YUAN-3T was investigated. The cell disruption techniques evaluated in this...A comparative evaluation of three different cell-disruption methods for the release of hydrogenase from H2 -producing bacterium E. harbinenase YUAN-3T was investigated. The cell disruption techniques evaluated in this study were uhrasonieation, high-speed homogenization and bead milling. Ultrasonication process was found to be the most effective method in terms of cell disruption. As for the specific activity of hydrogenase, there is no significant difference among the three kinds of methods. An orthogonal experiment L9 (34) was designed to optimize the procedures of ultrasonication for cell disruption. The optimized uhrasonication disruption conditions were the treatment at 250 W, 20 kHz, 30 s/15 s and 0. 30 g bacteria cell (dry weight) in 15 mL suspension buffer. As a result, the optimized conditions allow the hydrogenase to maintain the active form with the yield of 93.95 mg protein/g cell and the final activity of 0. 252 μmol/min/mg protein. In this work, we have developed and optimized an ultrasonication protocol for YUAN-3T cel]s, which is adapted to laboratory- scale release of hydrogenase proteins.展开更多
基金financial support from the National Basic Research Program of China(973 Program,No.2009CB930300)
文摘The objective of this work is to construct a nanosuspension drug delivery system of probucol,a BCS II drug,in order to improve its dissolution and oral bioavailability.The wet milling procedure using planetary beads-milling equipment was utilized to grind the raw probucol to ultrafine nanoparticle/nanocrystal aqueous suspension that was further solidified by freeze-drying process.Cellulose derivatives of different substitution groups and molecular weights,including HPMC,HPC,and MC,were evaluated as the primary stabilizer of probucol nanosuspension.Ternary stabilizers system composed of a primary stabilizer(cellulose derivative,i.e.HPC),a nonionic surfactant(Pluronic R F68),and an anionic surfactant(SDS)was employed to obtain probucol nanosuspension of finer particle size and enhanced dissolution in aqueous media.The probucol nanosuspension with good physical stability showed no obvious change of particle size even after storing over 7 d at 4°C or 25°C.The solidified probucol nanosuspension with trehalose as the cryoprotectant showed the highest dissolution rate(>60%at 2 h)compared to other cryoprotectant.The in vivo pharmacokinetic evaluation indicated about 15-folds higher AUC value of the probucol nanosuspension compared to that of coarse probucol suspension after oral administration to rats.The probucol nanosuspension prepared by wet-milling and ternary stabilizers system may find wide applications for improving the dissolution and oral absorption of water-insoluble drugs.
基金Item Sponsored by Grants-in-Aid from Ministry of EducationScience and Culture of Japan (No.23760645)
文摘Mg_(1-X)Cu_XFe_2O_4 type spinel ferrite was prepared by solid reaction method in order to discuss the heat generation ability in AC magnetic field.The cubic type ferrite structure was obtained for X=0-0.6 samples calcined at 1200℃,and the mixture phase of cubic and tetragonal structures were obtained for X=0.7,0.8 samples from XRD result. The highest lattice parameter and highest hysteresis loss value were also shown at X=0.6 sample,the crystal distortion was increased with increase the Cu^(2+)substitution in cubic type ferrite structure.The sized nano Mg_(0.4)Cu_(0.6)Fe_2O_4 powder was prepared by physical milling method using beads milling.The highest heat generation in the AC magnetic field was obtained for the 6 h milled samples using 0.1mm beads.The Cu^(2+)substitution for MgFe_2O_4 ferrite and the beads milling were very effective for the improvement of their heat generation ability in AC magnetic field.
文摘黑果花楸是一种具有很高营养价值和药用价值的小浆果树种,其果实中富含的多酚物质更是具有抗心血管病、抗肿瘤、抗氧化等生理活性,具有很高的开发价值。为了更好的开发利用黑果花楸,本研究以产自俄罗斯的黑果花楸果实为材料,采用珠磨法提取其体内的多酚物质,以多酚得率为指标设计6组单因素试验,根据6组单因素试验结果选取对多酚得率影响最大的3个因素,响应面法优化提取条件,最终得到最佳提取条件为:液料比为63.20 m L/g,时间为2.11h,珠填充量为61.65%,在此条件下,多酚得率理论上为27.29 mg/g,对其进行验证试验结果多酚得率为27.27 mg/g,误差为0.02%,证明试验结果可靠。本研究为黑果花楸果实多酚的提取工艺提供了参考,为黑果花楸的进一步开发利用提供了新思路及理论依据。
基金Sponsored by the Chinese Postdoctoral Science Foundation(Grant No.20070420861)the Heilongjiang Postdoctoral Fund(Grant No.LBH-Z07115)the National Natural Science Foundation of China(Grant No.31101316)
文摘A comparative evaluation of three different cell-disruption methods for the release of hydrogenase from H2 -producing bacterium E. harbinenase YUAN-3T was investigated. The cell disruption techniques evaluated in this study were uhrasonieation, high-speed homogenization and bead milling. Ultrasonication process was found to be the most effective method in terms of cell disruption. As for the specific activity of hydrogenase, there is no significant difference among the three kinds of methods. An orthogonal experiment L9 (34) was designed to optimize the procedures of ultrasonication for cell disruption. The optimized uhrasonication disruption conditions were the treatment at 250 W, 20 kHz, 30 s/15 s and 0. 30 g bacteria cell (dry weight) in 15 mL suspension buffer. As a result, the optimized conditions allow the hydrogenase to maintain the active form with the yield of 93.95 mg protein/g cell and the final activity of 0. 252 μmol/min/mg protein. In this work, we have developed and optimized an ultrasonication protocol for YUAN-3T cel]s, which is adapted to laboratory- scale release of hydrogenase proteins.