Preparation of ondansetron hydrochloride osmotic pump tablets and their in vitro drug release / 药学学报

<p><b>AIM</b>To prepare ondansetron hydrochloride osmotic pump tablets (OND-OPT) and investigate their in vitro drug release behavior.</p><p><b>METHODS</b>OND-OPT were prepared with a single punch press and pan coating technique. Osmotic active agents and plasticizer of coating film were chosen by drug release tests. The effects of the number, position and direction of drug release orifice on release behavior were investigated. The relation between drug release duration and thickness of coating film, PEG content of coating film and size of drug release orifice was established by uniform design experiment. The surface morphological change of coating film before and after drug release test was observed by scanning electron microscopy. The osmotic pumping release mechanism of OND-OPT was confirmed by drug release test with high osmotic pressure medium.</p><p><b>RESULTS</b>Lactose-mannitol (1:2) was chosen as osmotic active agents and PEG400 as plasticizer of coating film. The direction of drug release orifice had great effect on the drug release of OND-OPT without HPMC, and had no effect on the drug release of OND-OPT with HPMC. The OND-OPT with one drug release orifice at the centre of the coating film on one surface of tablet released their drug with little fluctuation. The drug release duration of OND-OPT correlated with thickness of coating film and PEG content of coating film, and didn't correlate significantly with the size of drug release orifice. OND-OPT released their drug with osmotic pumping mechanism predominantly.</p><p><b>CONCLUSION</b>OND-OPT are able to realize ideal controlled drug release.</p>

Preparation of solid lipid nanoparticles by microemulsion technique / 药学学报

<p><b>AIM</b>To prepare solid lipid nanoparticles by microemulsion technique.</p><p><b>METHODS</b>Stearic acid was used as the oil phase, lecithin as surfactant, alcohol as cosurfactant and distilled water as the aqueous phase. Microemulsion was prepared by mixing the above component in proper ratio. The corresponding pseudoternary phase diagram monitored Microemulsion formation field of different lecithin/alcohol. Solid lipid nanoparticles (SLN) were prepared by dispersing warm microemulsion in cold water under magnetic stirring. Then appropriate microemulsions that can contain more water phase and suitable oil phase were selected to prepare SLN. The influence of formulation, process variables on the preparation and quality of SLN were studied. Based on the investigation of single factors, orthogonal design was used to optimize SLN formulation and preparation process, and more, the reproducibility of the optimized results were studied.</p><p><b>RESULTS</b>The results showed that the device temperature (Ti), water temperature (Tw), and delivery rate (Rd) were the key factors that influence the preparation process of SLN, and Tw was extremely important. The ratio of microemulsion formulation, the ratio of microemulsion and distilled water had also influence on its quality.</p><p><b>CONCLUSION</b>Microemulsion technique can be used to prepare solid lipid nanoparticles.</p>