Morphology and Release Kinetics of Protein-Loaded Porous Poly(L-Lactic Acid) Spheres Prepared by Freeze-Drying Technique

Table 1

Averaged radius 𝑎, specific surface area 𝜎, and void content 𝑟_𝑣 of FDPLLA particle.

𝐶0 (wt%)		𝑎 (mm)	𝜎 (m^2 g^−1)	𝑑𝑓 (nm)^a	𝑟𝑣 (vol%)
2.0	Amorphous	1.47 ± 0.03	13.4	120	98.1
2.0	Crystallized	(0.8)			87.5
5.0	Amorphous	1.58 ± 0.07	11.9	135	94.4
5.0	Crystallized	(1.1)			85.0
8.0	Amorphous	1.49 ± 0.11	8.4	191	92.3
8.0	Crystallized	(1.1)			80.2

^aHypothetical membrane thickness estimated as 𝑑_𝑓=2/(𝜌𝜎).