Preparation of PLA and PLGA Magnetic Microspheres with T-Shaped Microchannel Reactor

Abstract:

Monodisperse magnetic microspheres with biomaterial of polylactic acid (PLA) or poly lactic-co-glycolic acid (PLGA) as shell were successfully prepared via T-shaped microchannel reactor in this paper. Hydrophilic ferriferrous oxide (Fe₃O₄) with highly magnetic responsiveness was obtained by solvothermal method. Aqueous solution of Fe₃O₄ was then emulsified into a dichloromethane solution of PLA or PLGA to generate water-in-oil (W/O) emulsion. Different stabilizer, i.e. polyvinyl alcohol (PVA), gelatin or gum arabic, was then added into the W/O emulsion for the purpose of more stable system. Subsequently, W/O/W composite emulsion was formed by injecting W/O emulsion into PVA aqueous solution at the T-shaped joint of microchannel reactor. Magnetic microspheres were finally prepared by solvent evaporation in the microchannel. The characteristic functional groups of Fe₃O₄ were characterized by Fourier transform infrared spectroscopy (FT-IR). The magnetic property was measured with vibrating sample magnetometer (VSM). The morphology of all samples was observed by scanning electron microscopy (SEM). It was found that the magnetic microspheres exhibit a uniform particle size in micro-scale. Therefore, the T-shaped microchannel reactor was expected to create a new approach for fabricating magnetic microspheres.

• Periodical: Key Engineering Materials (Volumes 609-610)
• Pages: 425-429
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.609-610.425
• Online since: April 2014
• Authors: Peng Liu, Yi Zhong, Yan Luo*
• Keywords: Biomaterial, Composite Emulsion, Magnetic Material, Monodispersity, T-Shaped Microchannel Reactor

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