title: Microencapsulation of puerarin nanoparticles by poly(l-lactide) in a supercritical CO(2) process.
abstract: Puerarin nanoparticles were firstly prepared in the process of solution-enhanced dispersion by supercritical CO(2) (SEDS) and then successfully microencapsulated by poly(l-lactide) (PLLA) in a modified SEDS process. By adding an organic non-solvent, an initial puerarin solution with a higher degree of saturation and lower concentration was obtained and applied in the SEDS process. The resulting puerarin nanoparticles were then suspended in PLLA solution and microencapsulated by PLLA in a modified SEDS process, where an 'injector' was employed in the particle suspension delivery system. The puerarin nanoparticles exhibited a good spherical shape, a smooth surface and a narrow particle size distribution with a mean particle size of 188 nm. After microencapsulation the puerarin-PLLA microparticles had a mean size of 675 nm, a drug load of 23.6% and an encapsulation efficiency of 39.4%; after a burst release at the first stage, the drug was released in a sustained process. Compared with the parallel study of a co-precipitation process, this microencapsulation process is a much more promising technique to prepare a drug-polymer carrier for a drug delivery system, especially for protein drugs.
authors.affiliation: Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
authors.forename: Ai-Zheng
authors.initials: AZ
authors.lastname: Chen
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.forename: Foo-Tim
authors.initials: FT
authors.lastname: Chau
authors.forename: Tsui-Yan
authors.initials: TY
authors.lastname: Lau
authors.forename: Jun-Yan
authors.initials: JY
authors.lastname: Hu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhao
authors.forename: Daniel Kam-Wah
authors.initials: DK
authors.lastname: Mok
mesh_terms: D000042:Absorption; D001672:Biocompatible Materials / Q000737:chemistry*; D002214:Capsules; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D003460:Crystallization / Q000379:methods; D004058:Diffusion; D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding / Q000379:methods*; D007529:Isoflavones / Q000008:administration & dosage / Q000737:chemistry*; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D013499:Surface Properties; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D002214:Capsules; D004337:Drug Carriers; D007529:Isoflavones; D011091:Polyesters; D014665:Vasodilator Agents; C033616:poly(lactide); C033607:puerarin