The porous structures of PHBV and composite scaffolds
were studied using a scanning electron microscope (SEM,
Stereoscan 440, UK) at 12 kV. Cubic SEM specimens were
cut from cylindrical scaffold samples using a sharp razor
blade after scaffold samples were frozen at –35
C for
1 day. SEM specimens were sputter-coated with a thin
layer of gold before examination. Energy dispersive X-ray
spectrometry (EDX, INCA 300, UK) was performed in
order to determine the presence and distribution of HA
nanoparticles in composite scaffolds. Compressive
mechanical properties of scaffolds were determined using a
mechanical tester (Instron 5848, USA) at a crosshead speed
of 0.5 mm/min. From each scaffold sample, cubic speci-
mens of 5 mm
·
5mm
·
5 mm were prepared for com-
pression tests. The compressive modulus of a scaffold
specimen was determined from the initial linear region of
the stress–strain curve. At least three scaffold specimens
were tested for each scaffold condition. Statistical analysis
was performed to determine the statistical significance
(
p
< 0.05) of differences in mechanical properties of
scaffolds of different conditions