Fig. 4

Physical and chemical characterization of the composites. A-C SEM photographs of PLGA/BGP composite in different magnifications and positions. The scale size is shown in the figure. D The single layer scan and (E) 3D reconstruction of PLGA/BGP composite based on micro-CT results. Bar = 1 mm. F The FT-IR spectra of the composites. G The release behavior of Nef in 24 h