College of Pharmaceutical Science, Nanjing University of Chinese Medicine, Nanjing 210046, PR China.
Carbohydr Polym. 2013 Jan 30;92(1):106-13. doi: 10.1016/j.carbpol.2012.08.084. Epub 2012 Aug 30.
Powder like samples named MVPS, containing 95.8% of polysaccharide, were extracted from a well-known marine bivalve Mactra veneriformis. Some in vitro tests were carried out to characterize its physicochemical properties. X-ray diffraction and thermodynamics tests indicated that MVPS were noncrystalline but thermostable polymers. Solubility and rheology tests showed that MVPS could easily dissolve in aqueous media and its solution obviously belonged to non-Newtonian fluids even at relatively high concentration. Furthermore, via blending MVPS solution with other polymers and then spray drying the blends, several composite microparticles were prepared. The chitosan/MVPS particles are available not only with spherical morphology but also with higher production yield. As a model drug, metformin can be encapsulated into the composite microsphere and then achieve the sustained release. The chitosan/MVPS composite microspheres loaded with drug might be an appropriate for nasal formulation since its particle sizes are in the range of 1-10 μm.
从一种著名的海洋双壳贝类 MVPS 中提取出粉末状的样品，含有 95.8%的多糖。进行了一些体外测试来表征其物理化学性质。X 射线衍射和热力学测试表明，MVPS 是非晶态但热稳定的聚合物。溶解度和流变学测试表明，MVPS 可以很容易地溶解在水介质中，其溶液即使在相对较高的浓度下也明显属于非牛顿流体。此外，通过将 MVPS 溶液与其他聚合物混合，然后喷雾干燥混合物，制备了几种复合微球。壳聚糖/MVPS 颗粒不仅具有球形形态，而且具有更高的产率。作为一种模型药物，二甲双胍可以被包封到复合微球中，然后实现缓释。载药的壳聚糖/MVPS 复合微球可能是一种合适的鼻用制剂，因为其粒径在 1-10μm 范围内。
