Generation of biodegradable drug-loaded polymer microspheres using hydrodynamic flow focusing

COLL 61

Thomas Schneider, Thomas.Schneider.81@gmx.net, Division of Pharmaceutics and Biopharmaceutics, Faculty of Pharmaceutical Sciences, The University of British Columbia, 2146 East Mall, Vancouver, BC V6T 1Z3, Canada and Urs Hafeli, Uhafeli@interchange.ubc.ca, Faculty of Pharmaceutical Sciences, University of British Columbia, 2146 East Mall, Vancouver, BC V6T 1Z3, Canada.
Hydrodynamic flow focusing is a seminal and easy to use technology enabling the generation of monodisperse droplets in a single step fashion. Using a polymer solution and various active components (drugs), hydrodynamic flow focusing gives rise to generate tailored monodisperse microspheres for pharmaceutical and life science applications (e.g., drug targeting) at low costs and high efficiency. So far only the successful encapsulation of fluorochrome dyes into non-biodegradable microspheres was reported using hydrodynamic flow focusing. Here we present a comprehensive parameter study to optimize the flow focusing process resulting in a dispersity of as low as 6% C.V. Furthermore, we present the encapsulation of the anti-cancer drug camptothecin in biodegradable poly(D,L-lactide-co-glycolide-acid) and poly(lactic-acid) microspheres (median 1.5 to 2.0 µm, C.V. = 14%) and a drug load of up to 0.65 wt% per polymer weight. Our studies showed continuous drug release in vitro over a period of 14 days.