Comparison of two preparation methods applied in tanshinone II(A)-loaded PLGA nanoparticles / 中国中药杂志

<p><b>OBJECTIVE</b>To optimize formulation of tanshinone II(A)-loaded PLGA nanoparticles and compare the difference of two methods in preparation and quality of nanoparticles.</p><p><b>METHOD</b>The two methods were nanoprecipitation method and emulsion-evaporation method. Single factor experiments and central composite design and response surface method were used to optimize the formulation of nanoparticles. The nanoparticles were characterized at size, morphology, entrapment efficiency, drug loading, drug recovery rate, crystallinity and drug release in vitro.</p><p><b>RESULT</b>The mean diameters were 225 nm and 183 nm, the entrapment efficiency were 95.49% and 87.99%, the drug loading were 2.03% and 0.16%, and the drug recovery rates were 38.42% and 17.59% respectively for nanoprecipitation method and emulsion-evaporation method.</p><p><b>CONCLUSION</b>Nanoprecipitation method was better than emulsion-evaporation method for preparation of tanshinone II(A)-loaded PLGA nanoparticles.</p>

An experirmental study on the preparation and drug sustained release characteristics of Pingyangmycin Albumin Microspheres / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The aim of this study was to prepare Pingyangmycin Albumin Microspheres (PYM-AMS) for arteriovenous malformations treatment.</p><p><b>METHODS</b>PYM-AMS was prepared at 140 degrees C by the method of emulsification-heat solidification and its characteristics were evaluated, such as morphosis, particle size, drug loading (DL%), encapsulation efficiency (EE%), stability and drug sustained-releasing in vitro. After being packaged, PYM-AMS were sterilized with 13.7 kGy of 60Co. Small samples of PYM-AMS were packaged in small bottles and stored at 3 - 5 degrees C, 15 - 25 degrees C, 37 degrees C for 3 months, then checked the change of morphology, DL, EE and the release rate.</p><p><b>RESULTS</b>The surface of particles was smooth and integrated. The average diameter of PYM-AMS particles was 139.422 microm and 80% was in the range of 56 - 251 microm. The mean DL% and EE% were 26.47% and 84.3%, respectively. PYM released fast in 5 h, but then released slowly. 88.65% drugs were released in 24 h, and t50 was 1.5 h. There was no obvious change of the morphology, DL,EE and the release rate of PYM-AMS stored at 3 - 5 degrees C 15 - 25 degrees C, 37 degrees C for 3 months.</p><p><b>CONCLUSION</b>PYM-AMS prepared in this study had sustained-release effect, high drug loading and high stability. Albumin is a good carrier of PYM embolization agent.</p>