Fig. 6 shows the absorbance obtained from an MTT assay of
L929 cells which were cultured with the extraction media in comparison
with control. It could be seen that statistically significant
differences (p < 0.05) were observed in the cell activity of L929 culture
for 48 h in the presence of CECS/PVA/SF nanofiber extract with
the diluted concentration of 50% or 100% in comparison with control,
but the viability of the cell still reached above 94% of that of
the negative control. This indicated that CECS/PVA/SF nanofiber
was extremely low toxic to L929 cells with high extraction concentrations,
which was probably owing to high cationic charge
densities of CECS and SF. However, when a 25% diluted extract of
CECS/PVA/SF nanofiber was used, no statistically significant differences
were observed in the cell activity in comparison with control,
which meant CECS/PVA/SF nanofiber was non-toxic to L929 cells
with low extraction concentration. All the results indicated that
SF/CECS/PVA nanofiber had good biocompatibility, which made it
as a good wound dressing for skin regeneration.