Recombinant human bone morphogenetic protein 2/poly(lactic-co-glycolic acid) copolymer microspheres with different particle sizes: preparation and release performance in vivo and in vitro  
Bao Yu-cheng, Wang Yong, Zhang Wen-long, Xie Yi, Yu Mei-li
Chinese Journal of Tissue Engineering Research . 2018, (2): 210 -215 .  DOI: 10.3969/j.issn.2095-4344.0008