Preparation and bioavailability of magnolol solid dispersions / 中草药

Objective: Hot-melt extrusion technique was applied to prepare magnolol solid dispersions, which can improve the in vitro solubility of magnolol and the in vivo bioavailability in rats. Methods: Four kinds of excipients, such as PS-630, HPC, EPO, and Soluplus, which were compatible with magnolol were used to prepare solid dispersions of different drug loadings by solubility parameter calculation. The prepared solid dispersion was characterized by differential scanning calorimetry (DSC), X-ray diffraction analysis (XRPD) and infrared spectroscopy (IR) using in vitro dissolution as an indicator; UPLC-MS/MS was used to evaluate the pharmacokinetic behavior of rats after oral administration of magnolol solid dispersion. Results: The in vitro dissolution test showed that the solid dispersion prepared by the 1:6 drug loading of PS-630, HPC, and EPO can significantly improve the dissolution of magnolol, and the drug was dispersed in the carrier in an amorphous state. The in vivo bioavailability test showed that the Cmax of magnolol in the solid dispersion prepared by PS-630 and HPC was about five times and 2.3 times that of the monomer, respectively, and the AUC0-t was increased about 37.22% and 70.88%, respectively. There was no increase in the EPO system. Conclusion: Hot melt extrusion technology can be successfully applied to improve the in vitro dissolution and in vivo bioavailability of the poorly soluble drug magnolol.

Optimization of preparation process and dissolution test of tetrandrine dropping pills / 中草药

Objective: To optimize the preparation process of tetrandrine dropping pills (TDP) and investigate the in vitro dissolution rate. Methods: Plackett-Burman experimental design was used to screen the critical factors in the preparation process of TDP from the ratio of matrix, ratio of matrix to drug, dropping temperature, dropping rate, dropping distance, and condensate temperature. The forming rate and weight variation of TDP were used as the evaluation index, the parameters in the preparation process of TDP were optimized by using the Box-Behnken response surface method. Moreover, the in vitro dissolution rate of TDP was compared with tetrandrine tablets by rotating basket method. Results: The Plackett-Burman experimental design results showed that the ratio of matrix, dropping temperature and condensate temperature had a significant effect on the forming rate of TDP. The optimum preparation parameters by Box-Behnken response surface method were as follows: the ratio of matrix was 2.6∶1, dropping temperature was 82.4 ℃ and condensation temperature was 7.5 ℃ with high forming rate, good roundness, stable weight, and fast drug dissolution rate of TDP. Conclusion: The quality of TDP by experimental design method can meet the requirements and can be further amplified.

Preparation of mesoporous silica nanoparticles in different pore size and its use in the solidification of sirolimus loaded self-microemulsifying drug delivery system / 药学学报

The mesoporous silica nanoparticles (MSN) in different pore size and sirolimus (SRL) loaded self-microemulsifying drug delivery system (SMEDDS) were prepared. The results in morphology were collected by scanning electron microscope, transmission electron microscope, small-angle X-ray diffraction, and N2 adsorption-desorption. The results showed that the prepared MSN has ordered nanochannels with a pore size of 6.3, 8.1, 10.8 nm, respectively. The particle size of SRL-SMEDDS were measured by particle sizing system, which was 20.6±1.3 nm. The stirring method was developed to prepare SRL-SMEDDS-MSN. It was found that the optimal ratio of SRL-SMEDDS to MSN was 2:1, while the drug loading rate was near 0.83%, and the flow properties of SRL-SMEDDS-MSN were of good condition. The differential scanning calorimetry results proving a molecular or amorphous dispersed state of SRL in MSN while the suspension experiment has shown great reconstitution properties of SRL-SMEDDS-MSN. There is no significant influence on maximum drug release rate of different pore size of SRL-SMEDDS-MSN in 250 mL water within 2 h, while the results of the first 40 min have an obvious difference. Above all, MSN might provide a new strategy for the solidification of SMEDDS.

Preparation of nanosuspensions of flavonoids from Glycyrrhizae Radix et Rhizoma and the in vitro dissolution rate / 中成药

AIM To prepare nanosuspensions of flavonoids from Glycyrrhizae Radix et Rhizoma and to determine the in vitro dissolution rate.METHODS Precipitation-high pressure homogenization method was adopted in the preparation of nanosuspensions.With mean particle size and polydispersity index (PDI) as evaluation indices,concentrations of flavonoids,povidone K30 (PVP K30) and polyethylene glycol 400 (PEG 400) as influencing factors,central composite design-response surface method was applied to optimizing the preparation.For the freedried powder prepared by freeze-drying method,the optimal kind and ratio of lyoprotectant were screened.Then the in vitro dissolution rates of freeze-dried powder and physical mixture were compared.RESULTS The optimal conditions were determined to be 10.00 mg/mL for flavonoids' concentration,and 2.30 mg/mL for both PVP K30 and PEG 400 concentrations,the mean particle size and PDI were (172.3 ± 1.2) nm and 0.175 ± 0.004,respectively.The optimal lyoprotectant was 5％ mannitol-lactose (3 ∶ 2),the mean particle size and PDI after redissolution were (239.7 ±2.1) nm and 0.193 ±0.032,respectively.The in vitro dissolution rate of lyoprotectant reached 87.7％ within 60 min,which was much higher than that of physical mixture (less than 30％).CONCLUSION Nanosuspension can effectively improve the in vitro dissolution rate of flavonoids from Glycyrrhizae Radix et Rhizoma.

Preparation of andrographolide-loaded solid dispersions / 中成药

AIM To prepare the andrographolide-loaded solid dispersions.METHODS Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD) were used for the analysis of solid dispersions previously prepared from the mixture of andrographolide and PVPK30 (1 ∶ 9) in autoclave.In addition to the evaluation index of in vitro dissolution rate,the influencing factors of pressure,temperature and reaction time were taken into consideration for the preparation optimization by Box-Behnken method.RESULTS Andrographolide was totally dispersed in solid dispersions in an amorphous state,manifesting an inhibited crystal diffraction peaks' formulation.Under the optimal conditions of 21.26 MPa for pressure,40.76 ℃ for temperature,and 1.13 h for reaction time,the in vitro dissolution rate was 85.49％.CONCLUSION After andrographolide is made into solid dispersions,its in vitro dissolution rate is obviously increased.

Preparation of Vitamin B1 Sustained-release Tablets / 中国药师

Objective: To screen the optimal formula and preparation process of vitamin B1 ( VB1 ) sustained-release tablets. Methods:The single-factor tests were used to investigate the type of filler, type and amount of matrix material hydroxypropyl methycel-lulose(HPMC), type and amount of retarder, tablet weight and core hardness. The orthogonal tests were used to investigate the amount of HPMC and ethyl cellulose( EC) and the core hardness. Results:The optimum formula was as follows:HPMC accounted for 50% of the tablet weight, EC accounted for 20%, the filler was lactose, the tablet weight was 200 mg and the tablet core hardness was 50 N. Conclusion:The prepared sustained-release tablets have significant controlled-release property, which provides reference for the devel-opment of new dosage form for VB1 .