Anna Song, Michigan State University

Anna earned her Bachelor degree in Materials Science and Engineering from Beijing University of Chemical Technology in China. She graduates with an honour of excellent graduation thesis in her undergraduate project on the poly(lactic acid) nano-porous scaffolds for bone tissue engineering.

Anna is now a second year Ph.D. student in Chemical Engineering and Materials Science in Michigan State University. Her current research topic is the preparation of biodegradable polymeric micro/nanoparticles and their application in drug delivery, tissue engineering, food safety and biomedical Nuclear Magnetic Resonance (NMR).


Preparation of poly(lactic acid)/polystyrene bioblend hollow microparticles embedded with nanoparticles via a one-step emulsion-diffusion method

Poly(lactic acid) (PLA) is widely used in packaging, biomedical engineering and pharmacy industry because of its biodegradation and biocompatibility. However, the brittleness and high cost of PLA limit its application. PLA combined with polystyrene (PS) has been considered as a potential bioblend since it reduces the cost compared with pure PLA and improve the degradation rate of PS.

In this work, PLA and PS have been dissolved in ethyl acetate under heating, which is a good solvent for PLA but a non-good solvent for PS. This PLA/PS blending solution has then been mixed with a 1:1(v/v) water/glycerol system to form an oil-in-water emulsion, which is followed by the diffusion process to obtain the spherical particles. From the SEM result, hollow microparticles embedded with nanoparticles can be clearly observed.

Electron energy loss spectroscopy (EELS) will be employed to define the composition of the dispersive nanoparticles and the continuous phase of the microparticles respectively. This type of microparticles can be used to design a 'two-stage', long time release system for antimicrobial food packaging and drug delivery due to the two separated polymer phases. The encapsulation and release of antimicrobials will be carried on in the future work.