缓释人富血小板血浆生长因子壳聚糖微球的制备

目的：制备载人富血小板血浆（hPRP）生长因子壳聚糖微球,观察其体外缓释效果。方法：选用离子凝胶法制备壳聚糖微球,利用微球吸附hPRP生长因子;以微球对hPRP中主要生长因子TGF-β1的吸附率作为评价指标,优化微球制备配方,并观察优化配方微球体外缓释TGF-β1效果;以hPRP中PDGF-AB为对象考察优化配方微球对其吸附率、载生长因子率,验证微球吸附效果。结果：当壳聚糖溶液浓度为2.5mg/ml、10mg/ml多聚磷酸钠溶液滴加量为2.5ml时可获得优化的壳聚糖微球制备配方。优化配方微球对hPRP中主要生长因子TGF-β1、PDGF-AB吸附率分别为78.02%、58.28%,载生长因子率分别为3.70ng/mg、1.31ng/mg;载hPRP生长因子的微球体外21天缓释TGF-β1累计35.80ng,占吸附总量的85.52%。结论：本实验制备的壳聚糖微球可初步实现吸附hPRP复合生长因子,并初步达到体外缓释效果。

Preparation of chitosan microspheres loaded with growth factors released from human platelet-rich plasma

Objective：To prepare chitosan microspheres loaded with growth factors released from human platelet-rich plasma （hPRP） and examine their controlled-release behavior.Methods：The chitosan microspheres were prepared by ionotropic gelation method,and multiple growth factors released from activated hPRP were loaded into the microspheres through an absorption process.The absorption efficiency of transforming growth factor β1 （TGF-β1） as one major growth factor in hPRP was used as the reference to assess the microsphere＇s ability of loading hPRP-released growth factors.The formulation of chitosan and tripolyphosphate （TPP） was modified to fabricate the optimal microspheres according to the absorption efficiency of TGF-β1.The absorption efficiency and loading efficiency of TGF-β1 and platelet-derived growth factor-AB （PDGF-AB） for the optimal microspheres were respectively measured and the controlled-release behavior of TGF-β1 for the microspheres was observed in vitro as well.Results：When the concentration of chitosan was 2.5mg/ml,and the adding volume of 10mg/ml TPP solution was 2.5ml,the formulation for the microspheres was the most optimal.The absorption efficiency of TGF-β1 and PDGF-AB for microspheres with optimal formulation was 78.02% and 58.28% respectively.The loading efficiency for TGF-β1 was 3.70ng/mg and 1.31ng/mg for PDGF-AB.The microspheres released 35.80ng TGF-β1 in 21 days in vitro which was 85.52% of the loaded amount.Conclusion：The prepared optimal chitosan microspheres could absorb multiple growth factors released from hPRP and the loaded TGF-β1 could be slowly released in vitro.