Insoluble breviscapin was chosen as the model drug. Bi-layer osmotic pump technology and gel matrix technology were used to prepare the breviscapin sustained and controlled release preparations. Dissimilarity factors (f1) and similarity factors (f2) were applied as similar judgment index to compare the effects of in vitro conditions on the release behavior of different types of breviscapin sustained and controlled release preparations. The tolerance of in vitro release conditions of bi-layer osmotic pump technology and gel matrix technology were studied. The results showed that in vitro release conditions have a greater impact on the gel matrix sustained release formulations, while have almost no effects on the osmotic pump controlled release formulations. Therefore, osmotic pump controlled release technology is less affected by the drug release environment. And it has a very good application prospect.
Delayed-Action Preparations ; Drug Carriers ; Excipients ; Flavonoids ; administration & dosage ; Hypromellose Derivatives ; Methylcellulose ; analogs & derivatives ; chemistry ; Osmolar Concentration ; Osmosis ; Polyethylene Glycols ; chemistry ; Rotation ; Technology, Pharmaceutical ; methods ; Temperature

An application of supercritical fluids technology for processing of budesonide-poly (ethylene oxide) solid dispersions was presented. The correlations of the operation parameters in the preparation process were studied. Solid dispersions of budesonide in poly (ethylene oxide) were prepared using a static method for supercritical carbon dioxide and characterized by powder X-ray diffractometry, differential scanning calorimetry, intrinsic dissolution, and in vitro dissolution. It was found that the optimum condition of solid dispersions formation was as follows: temperature, 40 degrees C ; pressure, 20 MPa; the ratio of budesonide and poly (ethylene oxide) , 1: 10. Drug existed in amorphous state in hydrophilic poly (ethylene oxide) carriers and intrinsic solubility and dissolution rates were significantly enhanced. The mechanism of the enhanced dissolution may be attributed to the amorphous character of the budesonide, improvement of the wettability of the hydrophobic budesonide, together with the formation of hydrogen bond of budesonide and hydrophilic poly (ethylene oxide). The supercritical fluids process can be used as an alternative method for preparation of solid dispersions.
Budesonide ; chemistry ; Calorimetry, Differential Scanning ; Carbon Dioxide ; Chromatography, Supercritical Fluid ; methods ; Drug Carriers ; Ethylene Oxide ; chemistry ; Powders ; Pressure ; Solubility ; Temperature ; Wettability ; X-Ray Diffraction

Solvents ; chemistry ; Technology, Pharmaceutical ; methods

AIMTo investigate the effects of surface modification of lactose carrier on performance of dry powder inhalations (DPIs).

METHODSModified lactose surface was prepared using a "particle smoothing" process to obtain smooth carrier surface and low surface energy with the presence of magnesium stearate, colloidal silica dioxide and talc. Inverse gas chromatography (IGC) was used to assess the surface energy of treated lactose, and the in vitro deposition of carrier-based IFNa-2b DPIs was evaluated with twin stage impinger.

RESULTSThe flowing property of lactose was greatly improved and the surface energy decreased by the "particle smoothing" process. Decreasing surface energy resulted in greater aspiration fraction of IFNa-2b.

CONCLUSIONIGC is a potentially useful tool for rapid formulation design and screening.

Administration, Inhalation ; Chromatography, Gas ; methods ; Drug Carriers ; administration & dosage ; chemistry ; Interferon-alpha ; administration & dosage ; chemistry ; Lactose ; administration & dosage ; chemistry ; Particle Size ; Powders ; Recombinant Proteins ; Stearic Acids ; chemistry ; Surface Properties ; Talc ; chemistry ; Technology, Pharmaceutical ; methods

AIMTo investigate the in vitro influencing factors on drug release from matrices with sodium alginate as the hydrophilic polymer.

METHODSSodium alginate hydrophilic matrix tablets were prepared by direct compression method with theopylline as a model drug. The in vitro influencing factors on drug release behavior from matrices were studied by investigating the swelling, water uptake and erosion characteristics of pure sodium alginate matrices.

RESULTSThe results showed that drug release rate and drug release mechanism were both related to the viscosity of sodium alginate used in matrices, pH values and ionic strength of dissolution media and rotation speeds.

CONCLUSIONSodium alginate can be tailor-made to suit the demands of applicants in sustained delivery systems as a good candidate of hydrophilic polymer.

Alginates ; administration & dosage ; chemistry ; Chemistry, Pharmaceutical ; Delayed-Action Preparations ; Drug Carriers ; Drug Delivery Systems ; Glucuronic Acid ; administration & dosage ; chemistry ; Hexuronic Acids ; administration & dosage ; chemistry ; Hydrogen-Ion Concentration ; Solubility ; Tablets ; Theophylline ; administration & dosage ; chemistry ; Viscosity

Objective To assay serum apelin level in obesity and newly-diagnosed type 2 diabetes mellitus (DM) patients and investigate the relationship between serum apelin level and body fat parameter,glucose and lipid metabolism and insulin resistance index,etc.Methods Sixty-two patients with type 2 DM and 72 subjects with normal glucose regulation (NGR) were selected and each group was divided into obese and non-obese subgroups according to body mass index (BMI)≥25 kg/m~2 or

The purpose of this study is to design push-pull osmotic pump (PPOP) tablets of famotidine using the expert system for the formulation design of osmotic pump of poor water-soluble drug which had been established by the authors. Firstly, the parameters which were requisite of the system input were obtained from literatures and experimental tests. Then the parameters were input into the system, and the program was run. The system displayed the designed formulations sequential. Finally, famotidine PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. It was found out that the target formulation of famotidine PPOP which could release for 24 hours was obtained in a very short period. Meanwhile, the practicability of the established expert system was proved.
Delayed-Action Preparations ; Drug Delivery Systems ; methods ; Excipients ; chemistry ; Expert Systems ; Famotidine ; administration & dosage ; chemistry ; Osmosis ; Solubility ; Tablets ; Water

Objective To analyse the characterisitics of daily blood glucose profiles of insulinoma using continuous glucose monitoring system(CGMS) and to investigate the value of CGMS in the diagnosis of insulinoma. Methods The blood glucose of 6 patients with pathologically-confirmed insulinoma(insulinoma group) were detected by CGMS for 3 consecutive days.The mean blood glucose(MBG),M-value of Schlichtkrull(M-value),frequency distribution of glucose levels and the hypoglycemic episodes of CGMS were measured,and the results were compared with those of normal glucose regulation(n=6,control group) and patients with newly-diagnosed type 2 diabetes with reactive hypoglycemia(n=5,diabetes group). Results The M-value of insulinoma group was significantly higher than that of control group(P0.05).The M-value and MBG of diabetes group were higher than those of insulinoma group and control group(P

Hydroxycamptothecin (HCPT) loaded PEG modified nanostructured lipid carriers (HCPT-PEG-NLC) and nanostructured lipid carriers (HCPT-NLC) were prepared by melt emulsification and homogenization method. The morphology, particle size and encapsulation efficiency of them were investigated. HCPT concentrations in plasma, heart, liver, spleen, lung, kidney and ovary were determined after iv of HCPT injection, HCPT-PEG-NLC and HCPT-NLC in mice. The targeting indexes of HCPT-PEG-NLC and HCPT-NLC were calculated. The transmission electron microscope imaging showed that HCPT-PEG-NLC and HCPT-NLC exhibited a spherical shape. The particle sizes of them were (88.6 +/- 22.5) and (127.2 +/- 43.4) nm. The encapsulation efficiency were (90.51 +/- 3.29)% and (84.37 +/- 2.81)%, respectively. After iv injection into the tail vein of mice, HCPT plasma concentrations of HCPT-PEG-NLC and HCPT-NLC were higher than that of HCPT injection at each sampling time. They also showed longer elimination time in every tissue. HCPT-NLC accumulated in endothelial system (RES), Re and Ce of it in liver and spleen were significantly higher than HCPT-PEG-NLC. HPCT-PEG-NLC prolonged circulation time and increased bioavailability of HCPT. MRT and AUC0-24 h of it were 19.80 and 17.02 times higher than those of HCPT injection. It also significantly reduced phagocytosis of RES, and showed lung targeting effect (Re and Ce were 14.51 and 41.35). To summarize, HCPT-PEG-NLC could prolong the circulation time of HCPT in vivo, and had the lung targeting effect. It was a promising carrier to increase therapeutic effect of HCPT in treating lung cancer.
Animals ; Antineoplastic Agents, Phytogenic ; administration & dosage ; blood ; chemistry ; pharmacokinetics ; Biological Availability ; Camptothecin ; administration & dosage ; analogs & derivatives ; blood ; chemistry ; pharmacokinetics ; Delayed-Action Preparations ; Drug Delivery Systems ; Drug Stability ; Female ; Lipids ; chemistry ; Lung ; metabolism ; Mice ; Mononuclear Phagocyte System ; physiology ; Nanoparticles ; Particle Size ; Phagocytosis ; drug effects ; Polyethylene Glycols ; chemistry ; Tissue Distribution

To screen a new poorly water-soluble antischistosomal drug QH917 self-microemulsifying drug delivery system which has steady release in vitro and absorption in situ separately. The formulation was optimized using central composite design-response surface methodology. Independent variables were oil content (%) and the weight ratio of surfactant and cosurfactant (Km), while response variables were self-microemulsifying time (t), mean particle size (PS) and polydispersity index (PI). The effects of ionic strength, food, pH, rotation speed and medium volume on drug release of the optimized formulation were evaluated under conditions simulating in vivo physiological situations. The absorption of the optimized formulation was studied using in situ intestinal permeability technique of rats. The optimized formulation was as follows: the content of media chain triglyceride (MCT) was 30%-34% (w/w); and the weight ratio of surfactant polyoxyl 40 hydrogenated castor oil (Cremophor RH40) and co-surfactant ethanol was 4.8-5.2. Release of QH917 from the optimized formulation was nearly unaffected by ionic strength, food, pH, rotation speed and medium volume. There was no marked difference of the absorption rate between rats with and without ligated bile duct in rat intestinal permeability technique. Inter-individual variability in absorption of the optimized formulation was negligible. Central composite design-response surface methodology is an efficient approach for optimizing formulations of self-microemulsifying drug delivery system; drug release in vitro and absorption behavior in situ of the optimized formulation is steady.
Animals ; Artemisinins ; administration & dosage ; pharmacokinetics ; Drug Delivery Systems ; methods ; Emulsions ; Intestinal Absorption ; Male ; Particle Size ; Random Allocation ; Rats ; Rats, Wistar ; Schistosomicides ; administration & dosage ; pharmacokinetics ; Solubility ; Surface-Active Agents ; chemistry ; Triglycerides ; chemistry