Controllable preparation of poly(lactic-co-glycolic acid) microspheres in capillary microreactors

PLGA microspheres were prepared controllably in capillary microreactors. • The microsphere size and size distribution were explored in depth. • PLGA liquid droplet and solid microsphere sizes were compared in detail. Poly(lactic-co-glycolic acid) (PLGA) microspheres are biodegradable materials with good biocompatibility and have demonstrated broad applications in medicine and biology. In this study, PLGA microspheres with controllable sizes and narrow size distributions were prepared using a coaxial microreactor combined with a solvent evaporation method. Based on droplet microfluidics, we systematically investigate the effects of continuous- and dispersed-phase flow rates, polymer solution concentration, and microreactor geometry on microsphere size and size distribution. The size and morphology of the PLGA microspheres were characterized using an inverted microscope coupled with image analysis software. The droplet generation process within the microchannels was also recorded using a high-speed camera mounted on the microscope. This work presents a straightforward and effective method for preparing monodisperse PLGA microspheres, with significant potential for biomedical applications. Fig. PLGA droplet and microsphere preparation. (a) Droplet generation process. (b) Microscopic image of PLGA droplets. (c) Microscopic image of PLGA microspheres. Download: Download high-res image (124KB) Download: Download full-size image