PURPOSE: The purpose of this study was to investigate the effect of the formulation parameters on the characteristics of dextran-based microspheres, prepared in an all-aqueous system. METHODS: Dextran microspheres were formed by polymerization of methacryloyl groups attached to dextran (dexMA), emulsified in an aqueous poly(ethylene glycol) (PEG) solution. DexMA/PEG/water phase diagrams were established. RESULTS: The binodals in the phase diagrams shifted to higher concentrations of dextran and PEG with decreasing molecular weight of both polymers, and with increasing degree of MA substitution. The volume-number mean diameter of the microspheres, varied between 2.5 and 20 microns. For a given formulation, the particle size was independent of the PEG/dexMA volume ratio > 40 and increased for volume ratios < 40. Furthermore, larger particles were obtained with decreasing viscosity of the continuous phase and increasing viscosity of the discontinuous phase. CONCLUSIONS: Particle characteristics of dextran microspheres prepared in an all-aqueous system, among which the size and initial water content, can be tailored by adjusting the formulation parameters.
PURPOSE: The purpose of this study was to investigate the effect of the formulation parameters on the characteristics of dextran-based microspheres, prepared in an all-aqueous system. METHODS:Dextran microspheres were formed by polymerization of methacryloyl groups attached to dextran (dexMA), emulsified in an aqueous poly(ethylene glycol) (PEG) solution. DexMA/PEG/water phase diagrams were established. RESULTS: The binodals in the phase diagrams shifted to higher concentrations of dextran and PEG with decreasing molecular weight of both polymers, and with increasing degree of MA substitution. The volume-number mean diameter of the microspheres, varied between 2.5 and 20 microns. For a given formulation, the particle size was independent of the PEG/dexMA volume ratio > 40 and increased for volume ratios < 40. Furthermore, larger particles were obtained with decreasing viscosity of the continuous phase and increasing viscosity of the discontinuous phase. CONCLUSIONS: Particle characteristics of dextran microspheres prepared in an all-aqueous system, among which the size and initial water content, can be tailored by adjusting the formulation parameters.
Authors: Amanda W Smith; Claire E Segar; Peter K Nguyen; Matthew R MacEwan; Igor R Efimov; Donald L Elbert Journal: Acta Biomater Date: 2011-08-30 Impact factor: 8.947
Authors: Christian Celia; Silvia Ferrati; Shyam Bansal; Anne L van de Ven; Barbara Ruozi; Erika Zabre; Sharath Hosali; Donatella Paolino; Maria Grazia Sarpietro; Daniel Fine; Massimo Fresta; Mauro Ferrari; Alessandro Grattoni Journal: Adv Healthc Mater Date: 2013-07-23 Impact factor: 9.933
Authors: K D F Vlugt-Wensink; R de Vrueh; M G Gresnigt; C M Hoogerbrugge; S C van Buul-Offers; L G J de Leede; L G W Sterkman; D J A Crommelin; W E Hennink; R Verrijk Journal: Pharm Res Date: 2007-10-11 Impact factor: 4.200