title: Preparation of nanoparticles by solvent displacement using a novel recirculation system.
abstract: Submicron colloidal suspensions of poly(epsilon-caprolactone) (PCL) were prepared by the solvent displacement method, using either the conventional form or a new recirculation device. In the latter case, a process that allows the recirculation of the aqueous phase into a device, providing a continuous flow, is proposed. The influence of the organic solution injection rate and polymer concentration on mean particle size and process yield were studied for both methods. The recirculation rate was also analyzed for the recirculation system. Nanoparticles (NPs) showed mean sizes that ranged from 156 to 381. The smallest particles were obtained when recirculation rate, injection rate and polymer concentration were maximized but at the expense of the yield. The only acceptable yields (83-96%) were obtained at the lowest PCL concentration (2.5% w/v). ANOVA tests (alpha = 0.05) showed that the variables implicated in the recirculation system significantly affected the mean particle size and the process yield. The entrapment efficiencies of NPs prepared by the conventional method were not significantly different (alpha = 0.05) from those obtained by the recirculation system.
authors.affiliation: Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Estado de México, México.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Piñón-Segundo
authors.forename: Adriana
authors.initials: A
authors.lastname: Ganem-Quintanar
authors.forename: Juan
authors.initials: J
authors.lastname: Rafael Garibay-Bermúdez
authors.forename: José
authors.initials: J
authors.lastname: Juan Escobar-Chávez
authors.forename: Miriam
authors.initials: M
authors.lastname: López-Cervantes
authors.forename: David
authors.initials: D
authors.lastname: Quintanar-Guerrero
mesh_terms: D003102:Colloids; D004337:Drug Carriers / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000627:therapeutic use; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry / Q000627:therapeutic use; D012997:Solvents; D014867:Water
chemical_list: D003102:Colloids; D004337:Drug Carriers; D011091:Polyesters; D012997:Solvents; D014867:Water; C016240:polycaprolactone