Preparation and in vitro quality evaluation of silybin supersaturated self-microemulsion drug delivery system / 中草药

Objective: To develop and optimize the silybin supersaturated self-microemulsion drug delivery system (SLB-SSMEDDS) and improve the oral bioavailability of SLB in the biological medium. Methods: The formulation of SLB-SMEDDS was selected by solubility test, emulsifying ability of emulsifier and pseudo-ternary phase diagram. The analytic hierarchy process (AHP) was used to evaluate the performance of each prescription to screen the optimal ratio. The type and dosage of precipitation inhibitors (PPIs) was optimized to maintain the supersaturation and duration of drugs in biological media in vitro; Finally, the emulsification effect, emulsion size and surface morphology of SLB-SSMEDDS was comprehensively evaluated in terms of in vitro release and in vitro supersaturation. Results: The SLB-SSMEDDS prescription was Capryol 90-Cremophor RH-Transcutol HP-HPMC-AS MF (10:67.5:22.5:2). The self-microemulsion with a drug loading of 50.19 mg/g was uniform and the emulsion droplets were spherical in shape and uniform in size. And the emulsification time was (30.67 ± 4.16) s, the average particle size was (11.67 ± 0.81) nm, and the PDI was (0.15 ± 0.04). The dissolution rate of SLB-SSMEDDS in FaSSGF and FaSSIF-V2 was significantly increased. And the in vitro dilution and supersaturation could be maintained above 10 within 120 min. Conclusion: SLB-SSMEDDS has a simple preparation process and can improve the stability of traditional SMEDDS, maintain supersaturation effectively and enhance the dissolution of SLB in vitro.

Study on preparation technology of nano spray drying for Rehmanniae Radix oligosaccharide micro-powders / 中草药

Objective: To prepare Rehmanniae Radix oligosaccharide micro-powders with high load capacity, high yield, and good moisture absorption, using nano spray drying technology. Methods: Based on the single factor experiments, the B-90 spray dryer was used to prepare Rehmanniae Radix oligosaccharide micro-powders with average particle size, yield, and moisture absorption rate as evaluation indices, and orthogonal test was used to investigate the influence of inlet temperature, spray drying efficiency, and solution concentration on the preparation process and to optimize the preparation process. Results: The best spray drying condition was A2B2C3, namely the inlet temperature was 110℃, the spray drying efficiency was 50%, and the drug concentration was 1%. Finally the drug loading was 30% and the yield was 89% with good moisture absorption. The Rehmanniae Radix oligosaccharide micro-powders had good morphology stability. Conclusion: The nano spray drying technology is stable and the micro-powders have good quality, which is better than the traditional spray drying technology.

Optimization of rutaecarpine solid lipid nanoparticles by central composite design and response surface methodology / 中草药

Objective: To optimize the prescription of rutaecarpine solid lipid nanoparticles (Rut-SLN). Methods: Using the film-ultrasound method to lining-up the Rut-SLN, with the entrapment efficiency (EE), Zeta potential, and the average particle size as the evaluation indexes, using central composite design to inspect the effects of glycerol monostearate/drug quality ratio (A), soybean lecithin for injection/glycerol monostearate mass ratio (B), Poloxamer 188 (C) on three factors of the EE, Zeta potential, and average particle size. Prediction and analysis for selecting the best prescription condition were carried out by using the response surface method. Results: According to the optimized prescription, the EE, Zeta potential, and the average particle size of Rut-SLN was respectively 84.27%, 122.6 nm, and -20.7 mV. Conclusion: The optimal prescription of Rut-SLN has better stability, feasibility, and high EE, which is suitable for the production.

Preparation process of apigenin particles by supercritical CO2 anti-solvent method / 中草药

Objective: To prepare the apigenin particles by supercritical CO2 anti-solvent technology, to optimize the preparation process of apigenin particles on the basis of single factor experiments using the average particle size as evaluation index through orthogonal test design, and to investigate the in vitro dissolution rate. Methods: The particle size distribution, scanning electro- microscope (SEM) analysis, infrared spectrum (IR), and differential scanning calorimetry (DSC) were used to validate the selected process. The external dissolution rates of apigenin ingredient and apigenin particles of the optimal process were tested to speculate the bioavailability of apigenin. Results: The optimal process conditions by orthogonal test were set as follows: The proportion of acetone and dimethyl sulfoxide (DMSO) was 24:1, temperature was 40°C, pressure was 10 MPa, solution volumetric flow rate was 2.0 mL/min, and mass concentration of apigenin was 8 mg/mL. Under the optimal conditions, the volume average particle size was obviously smaller than that of ingredient. And the shapes of apigenin were irregular. FTIR and DSC analyses showed that the chemical structure did not change. The results showed that the in vitro dissolution rate of apigenin particles of the optimal process was significantly larger than that of apigenin ingredient. Conclusion: The supercritical CO2 anti-solvent technology is feasible to prepare apigenin particles and promote its bioavailability, and it provides a reference basis for preparing ultrafine particles.

Research on preparation technology of baicalein particles by supercritical CO2 antisolvent method / 中草药

Objective: The preparation technology of baicalein microparticles was optimized with volume average particle size (VAPS) of micropaticles as the evaluation index. Methods: The baicalein micropartocles were prepared by supercritical CO2 antisolvent method. On the basis of single factor tests, orthogonal design was used to optimize the preparation process of baicalein microparticles. The microparticle size distribution, scanning electron microscopy (SEM) analysis, infrared spectrum (IR), and differential scanning calorimetry (DSC) were used to analyze the microparticles. Results: The suitable conditions optimized by orthogonal test were set as follows: solvent flow rate 0.75 mL/min, pressure 8 MPa, temperature 48 °C, and mass concentration of baicalein 4 mg/mL. Under the optimum conditions, the VAPS of the prepared microparticles was obviously smaller than that of the baicalein. And the shapes of baicalein in prepared microparticles were irregular under SEMA. IR and DSC analyses showed that the chemical structure of baicalein microparticles was not changed while the thermodynamic properties of baicalein might change. Meanwhile, the purity of baicalein became higher after the treatment. Conclusion: Supercritical CO2 antisolvent method is feasible to prepare baicalein microparticles and provides a reference basis for preparing microparticles at the same time.