Solid dispersion of fenofibrate （FNB）, a poorly water-soluble drug, was prepared by a fluid-bed coating technique with PEG 6000 as the carrier. The physical state was characterized by DSC and X-ray powder diffractom...Solid dispersion of fenofibrate （FNB）, a poorly water-soluble drug, was prepared by a fluid-bed coating technique with PEG 6000 as the carrier. The physical state was characterized by DSC and X-ray powder diffractometry, which indicated the existence of fenofibrate in crystalline form in the solid dispersion. In vitro dissolution was studied in water containing 1% sodium lauryl sulfate, FASSIF and FESSIF. Significant enhancement in dissolution was achieved at PEG/FNB ratio of 4/1 with near complete dissolution within 30 min. Moderate improvement in dissolution rate was observed at smaller PEG/FNB ratios. Oral bioavailability was studied in beagle dogs after oral administration of fenofibrate solid dispersion pellets by monitoring fenofibric acid in plasma. The oral bioavailability of PEG/FNB 3/1 and 4/1 solid dispersion pellets was improved by 3.4 and 4.4-fold as compared to Lipanthyl, a commercial micronized fenotibrate formulation. There was a strong dependence of oral bioavailability on the in vitro dissolution rate. Good correlation was observed between the in vivo absorption fraction and the in vitro dissolution rate in each of the dissolution media, water containing 1% sodium lauryl sulfate, FASSIF and FESSIF. It could be concluded that PEG/FNB solid dispersion pellets were able to improve the dissolution and oral bioavailability of fenofibrate.展开更多
The gasification wastewater is a kind of typical organic industrial wastewater with high chemical oxygen demand （COD） and ammonia nitrogen, which could not be completely degraded by the traditional physical, chemica...The gasification wastewater is a kind of typical organic industrial wastewater with high chemical oxygen demand （COD） and ammonia nitrogen, which could not be completely degraded by the traditional physical, chemical and biological method. So it is very important to find an effective treatment process. A combination process of catalytic oxidation with noble metal catalysts and aerobic biological fluid-bed packed with the new ultrastructure biological carriers, which was developed by ourselves, was investigated to treat the gasification wastewater. The pilot scale test with 0.5 m^3/h influent flow was carried out to investigate the performance of this new combination process. The results showed that the effluent COD was 84.02 mg/L, ammonia nitrogen was 14.15 mg/L, and total phenol was 0.20 mg/L, which could completely meet the Grade I of Wastewater Discharge Standard （GB8978-1996）, when the influent average COD was 5 564 mg/L, ammonia nitrogen was 237 mg/L, and total phenol was 1 100 mg/L. The two catalytic reactors could evidently improve the wastewater biodegradability, and the value of BOD5/COD （B/C） increased from 0.23 to 0.413 in the one-stage catalytic reactor and from 0. 273 to 0.421 in two-stage catalytic reactor. The further experiment results showed that the effluent quality of this new combination process could still meet the discharge standard, when the COD loading was 8.65 kg / （m^3· d）. Most of aromatic and heterocyclic compounds were degraded effectively in this combination process.展开更多
The pulsed-spray fluid-bed granulation (PSFBG) process was investigated and optimized using definitive scree ning design, a recently proposed new class of three-level desig n of experiment method. Such a design enable...The pulsed-spray fluid-bed granulation (PSFBG) process was investigated and optimized using definitive scree ning design, a recently proposed new class of three-level desig n of experiment method. Such a design enabled quadratic models to be established that described the effect of six in put process parameters - inlet air temperature, inlet air humidity, binder spray rate, atomization pressure, pulse period, and pulse width - on the granule quality in a PSFBG process. Mathematical models of the mean particle size, relative size distribution width, production yield, and porosity were developed to quantify the relationships between the in flue ncing factors and critical quality attributes. On the basis of con strai nts on the desired granule properties, a design space for PSFBG was determined and ranges of the operating parameters were defined. An acceptable degree of prediction was confirmed by validation experiments, demonstrating the reliability and effectiveness of using definitive screening design to study the PSFBG process. This method can accelerate screening and optimization of this process within a large multidimensional design space.展开更多
Meloxicam-β-cyclodextrin （ME-β-CD） inclusion complex was prepared by a fluid-bed coating technique upon solvent removal and simultaneous depositing onto the surface of nonpareil pellets and using PVP K30 as a bind...Meloxicam-β-cyclodextrin （ME-β-CD） inclusion complex was prepared by a fluid-bed coating technique upon solvent removal and simultaneous depositing onto the surface of nonpareil pellets and using PVP K30 as a binding agent to facilitate good coating. The resultant pellets were spherical and intact in shape with good flowability and friability. SEM analysis showed that the pellets were smooth and had a tightly coated inclusion complex layer. In vitro dissolution of the inclusion complex pellets in pH 7.4 phosphate buffer was dramatically enhanced at an ME/CD ratio of 1/1. DSC and powder X-ray diffractometry proved the absence of crystallinity in the ME/CD inclusion complexes. Moreover, Fourier transform-infrared spectrometry together with Raman spectrometry indicated that the thiazole ring of ME was possibly included in the cavity of β-CD.展开更多
基金Shanghai Municipal Committee of Science and Technology (Grant No. 0852nm04400)
文摘Solid dispersion of fenofibrate （FNB）, a poorly water-soluble drug, was prepared by a fluid-bed coating technique with PEG 6000 as the carrier. The physical state was characterized by DSC and X-ray powder diffractometry, which indicated the existence of fenofibrate in crystalline form in the solid dispersion. In vitro dissolution was studied in water containing 1% sodium lauryl sulfate, FASSIF and FESSIF. Significant enhancement in dissolution was achieved at PEG/FNB ratio of 4/1 with near complete dissolution within 30 min. Moderate improvement in dissolution rate was observed at smaller PEG/FNB ratios. Oral bioavailability was studied in beagle dogs after oral administration of fenofibrate solid dispersion pellets by monitoring fenofibric acid in plasma. The oral bioavailability of PEG/FNB 3/1 and 4/1 solid dispersion pellets was improved by 3.4 and 4.4-fold as compared to Lipanthyl, a commercial micronized fenotibrate formulation. There was a strong dependence of oral bioavailability on the in vitro dissolution rate. Good correlation was observed between the in vivo absorption fraction and the in vitro dissolution rate in each of the dissolution media, water containing 1% sodium lauryl sulfate, FASSIF and FESSIF. It could be concluded that PEG/FNB solid dispersion pellets were able to improve the dissolution and oral bioavailability of fenofibrate.
基金the Key Project in Science and Technology of Heilongjiang Province , China (No. GB06C20401)
文摘The gasification wastewater is a kind of typical organic industrial wastewater with high chemical oxygen demand （COD） and ammonia nitrogen, which could not be completely degraded by the traditional physical, chemical and biological method. So it is very important to find an effective treatment process. A combination process of catalytic oxidation with noble metal catalysts and aerobic biological fluid-bed packed with the new ultrastructure biological carriers, which was developed by ourselves, was investigated to treat the gasification wastewater. The pilot scale test with 0.5 m^3/h influent flow was carried out to investigate the performance of this new combination process. The results showed that the effluent COD was 84.02 mg/L, ammonia nitrogen was 14.15 mg/L, and total phenol was 0.20 mg/L, which could completely meet the Grade I of Wastewater Discharge Standard （GB8978-1996）, when the influent average COD was 5 564 mg/L, ammonia nitrogen was 237 mg/L, and total phenol was 1 100 mg/L. The two catalytic reactors could evidently improve the wastewater biodegradability, and the value of BOD5/COD （B/C） increased from 0.23 to 0.413 in the one-stage catalytic reactor and from 0. 273 to 0.421 in two-stage catalytic reactor. The further experiment results showed that the effluent quality of this new combination process could still meet the discharge standard, when the COD loading was 8.65 kg / （m^3· d）. Most of aromatic and heterocyclic compounds were degraded effectively in this combination process.
文摘The pulsed-spray fluid-bed granulation (PSFBG) process was investigated and optimized using definitive scree ning design, a recently proposed new class of three-level desig n of experiment method. Such a design enabled quadratic models to be established that described the effect of six in put process parameters - inlet air temperature, inlet air humidity, binder spray rate, atomization pressure, pulse period, and pulse width - on the granule quality in a PSFBG process. Mathematical models of the mean particle size, relative size distribution width, production yield, and porosity were developed to quantify the relationships between the in flue ncing factors and critical quality attributes. On the basis of con strai nts on the desired granule properties, a design space for PSFBG was determined and ranges of the operating parameters were defined. An acceptable degree of prediction was confirmed by validation experiments, demonstrating the reliability and effectiveness of using definitive screening design to study the PSFBG process. This method can accelerate screening and optimization of this process within a large multidimensional design space.
基金the School of Pharmacy,Fudan University,for financial support
文摘Meloxicam-β-cyclodextrin （ME-β-CD） inclusion complex was prepared by a fluid-bed coating technique upon solvent removal and simultaneous depositing onto the surface of nonpareil pellets and using PVP K30 as a binding agent to facilitate good coating. The resultant pellets were spherical and intact in shape with good flowability and friability. SEM analysis showed that the pellets were smooth and had a tightly coated inclusion complex layer. In vitro dissolution of the inclusion complex pellets in pH 7.4 phosphate buffer was dramatically enhanced at an ME/CD ratio of 1/1. DSC and powder X-ray diffractometry proved the absence of crystallinity in the ME/CD inclusion complexes. Moreover, Fourier transform-infrared spectrometry together with Raman spectrometry indicated that the thiazole ring of ME was possibly included in the cavity of β-CD.
文摘化学链燃烧技术是一种基于固体载氧体颗粒的新型无焰燃烧技术,对于助力碳减排具有重要意义。载氧体颗粒的寿命制约着该技术的进一步应用。文中针对载氧体颗粒的碰撞磨损问题,采用计算流体力学-离散元法(computational fluid dynamics-discrete element method,CFD-DEM)双向耦合数值计算法,建立非规则载氧体颗粒模型,从颗粒速度场、碰撞频率场及碰撞功率场三方面,探究冷态流化床内载氧体颗粒的运动状态、分布特征及碰撞情况。结果表明,冷态流化床内载氧体颗粒呈现上下无序周期性运动,单周期内流化床空间上出现颗粒密相区与稀相区。其中,稀相区颗粒速度大而碰撞频率小,颗粒具有高动能与高重力势能;密相区内颗粒速度小而碰撞频率高,最大碰撞频率对应的颗粒多为大粒径、较小长径比,且颗粒能量低;颗粒最易磨损区即碰撞最大功率区(最大7.8×10^(−8)W)位于颗粒密相区与稀相区的交界面,颗粒碰撞磨损能量由颗粒动能与重力势能累积提供。研究结果揭示了冷态流化床内载氧体颗粒的碰撞磨损机制。
