ABSTRACT
Objective:To prepare the self-microemulsifying drug delivery system (SMEDDS) and relevant tablets of atorvastatin calcium and ezetimibe(Ato-Eze),and investigate the in vitro release of Ato-Eze SMEDDS tablets. Methods:The solubility and excip-ient compatibility of Ato and Eze in different excipients were investigated. The pseudo-ternary phase diagram composed of different oil phase,emulsifier and co-emulsifier was used to obtain the self-emulsifying area. The morphology,particle size distribution and zeta po-tential of microemulsion were determined by a dilution method. The optimal formula of Ato-Eze SMEDDS was prepared into tablets. The drug release profiles of the commercial formula,Ato-Eze SMEDDS and Ato-Eze SMEDDS tablets were compared. Results:The op-timal formula was as follows:propylene glycol monocaprylate as the oil phase,Solutol HS 15 as the surfactant and polyethylene glycol 600 as the co-surfactant with the best ratio of 5 :3.75:1.25. Ato-Eze SMEDDS was a clear and transparent microemulsion solution with homogeneous small spheres as seen under a transmission electron microscope. The particle size and zeta potential of Ato-Eze SMEDDS was(44.2 ± 19.5) nm and( -24.1 ± 1.3) mV,respectively. The in vitro release profile indicated that the accumulated re-lease of Ato-Eze SNEDDS and the tablets reached up to nearly 100% in 45 min. Conclusion: Ato-Eze SMEDDS tablets can signifi-cantly improve the in vitro dissolution rates of the two drugs,and the preparation process is simple and feasible.
ABSTRACT
To prepare simvastatin nanostructured lipid carriers ( simvastatin-NLCs) . Methods:The simvastatin-NLCs were prepared by melt-emulsion ultrasonication and low temperature-solidification methods. Using the particle size, polydispersion in-dex, encapsulation efficiency and drug loading as the idices, the ratio of solid to liquid, lipid concentration, ratio of surfactant to cosur-factant, emulsifier concentration and drug concentration were optimized. The optimized simvastatin-NLCs were characterized for the en-capsulation efficiency, particle size, zeta potential and morphology. In vitro drug release behavior and stability of NLCs were also stud-ied. Results:The optimized simvastatin-NLCs formula was as follows:the concentration of simvastatin, cetyl palmitate, Miglyol? 812, soy lecithin and solutol HS15? was 0. 5%, 1. 5%, 4. 5%, 2. 5% and 1. 5%, respectively. The particle size and zeta potential of NLCs was (102. 2 ± 42. 1) nm and ( -33. 1 ± 4. 1) mV, respectively. The simvastatin-NLCs were found to be small and spherical with smooth surface under a transmission electron microscope. The in vitro release profile indicated that the accumulated release of sim-vastatin reached up to (59. 1 ± 4. 8) % in 24 h. The stability studies showed that simvastatin-NLCs were stable in 3 months after stored at 5℃. Conclusion:The formula of simvastatin-NLCs prepared by melt-emulsion ultrasonication and low temperature-solidifica-tion method is feasible.
ABSTRACT
Objective:To prepare sustained-release pellets of memantine hydrochloride and investigate the in vitro drug release be-havior. Methods:The drug-loaded pellets were prepared by a fluid bed coating technology, the sustained-release pellets were prepared with Eudragit RL 30D and Eudragit RS 30D as the coating materials, and in vitro drug release behavior of the sustained-release pellets was studied. Results:The in vitro drug release was steady and complete in 24h, which fit a zero-order kinetics model. Conclusion:The memantine hydrochloride sustained-release pellets has the sustained-release property.
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Objective:To study the in vitro and in vivo anti-tumor effect of lentinan combined with 5-FU. Methods:MTT method was used to determine the proliferation of H22 in vitro, and the cell cycle changes were analyzed by a flow cytometry. The in vivo anti-tumor effect was evaluated in Kunming mice. The tumor inhibitory rate, thymus/spleen index, IL-2, IL-6 and TNF-α were deter-mined. Results:The in vitro results revealed that lentinan had no obvious effect on the inhibitory rate and cell cycle of the cells treated with 5-FU. In vivo results showed that lentinan at the dosage of 25 and 50 mg·kg-1 could obviously enhance the anti-tumor effect of 5-FU(P<0. 05). Furthermore, lentinan could increase the thymus/spleen index of the tumor-bearing mice. Conclusion:Lentinan com-bined with 5-FU has synergistic effects on anti-tumor activity through nonspecific immune stimulation rather than the direct killing of tumor cells.
ABSTRACT
Objective:To develop a dissolution method for olanzapine pamoate long-acting injections. Methods:The in vitro dis-solution profile of olanzapine pamoate was detected by an oar method and an HPLC method. The stirring speed respectively was 25, 50 and 75 r·min-1, and 500 ml of sodium lauryl sulfate simulated muscle fluid [0.5% , with pH of (7.0 ±0.05)] at (37 ±0.5)℃was used as the bio-relevant dissolution media. Results: The linearity between the peak areas and the concentrations was observed within the range of 2. 15-107. 40 mg·L-1(r=0. 999 9) for pamoate and 1. 75-87. 40 mg·L-1(r=0. 999 9) for olanzapine, respec-tively, and the average recovery of olanzapine pamoate was 99. 80%(RSD=0. 55%, n=9). The f2 for the dissolution in the dissolu-tion medium of shelf-prepared products and the innovation preparations was 70. 80. Conclusion:The dissolution method can be utilized to control the quality of olanzapine pamoate long-acting injections.