Rheological characteristics of drug-loaded microemulsions and their printability in three dimensional printing systems

Rheological properties of microemulsions(MEs) and their printability in three dimensional printing(3DP) systems were investigated.A series of MEs with different contents of oil phase were prepared using sonication method with ibuprofen as model drug and soybean lecithin as emulfier.Stationary and transient rheological properties of MEs were investigated by ARES-SRF using concentric cylinders measuring systems.3DP systems with piezoelectric drop-on-demand print heads were employed to test the printability of the MEs.Results demonstrate that the apparent viscosity and dynamic linear viscoelastic regions of the MEs are the most important parameters for continuous and stable printing of MEs by 3DP.The incorporation of drug in the MEs has little influence on the MEs' stationary rheological behaviors and dynamic viscoelasticity,but the concentration of oil phase has a strong influence on them.The rheological property of binder liquids has a close relationship with their printability in 3DP system.

速溶电纺载药PVP纳米纤维膜制备与表征

采用电纺工艺制备载豆腐果苷聚乙烯基吡咯烷酮纳米纤维膜.通过偏光显微镜确定电纺条件,利用扫描电镜对纤维膜表面形态进行观察;采用X-射线晶体衍射（XRD）和差示扫描量热分析（DSC）检测纤维膜中药物的存在状态,通过红外光谱分析药物与纤维基材之间的相互作用.结果表明载药纤维直径分布均匀（400-600 nm）、表面光滑无药物颗粒,药物与聚合物之间通过氢键作用、具有良好的相容性,XRD和DSC结果表明药物以无定形态高度分散于纳米纤维中,纤维膜中药物以＂聚合物控释＂机制在13.7 s左右完全溶解.

电纺载药纳米纤维改善难溶药物溶解性能研究

一直以来,研究人员不断寻求改善药物溶解性能的技术或策略,以提高药物的生物利用度,增进疗效,降低毒性。这些技术或策略基本上可概括为两类：一类是化学方法,通过改变难溶解药物的理化性能,提高其水溶性,增强其透膜性能,如药物改性PEG化、糖化、合成水溶性前体药物、合成磷脂等各种复合物;另一类是物理方法,即尽可能减小药物颗粒的粒径或物理存在状态,如微粉化、通过环糊精包合、制备固体分散体等。