*2.9. Cytocompatibility*

Mouse L929 fibroblast cells were seeded at a density of 5000 cells/cm<sup>2</sup> in 96-well plates and incubated in MEMα (Wako Pure Chemical, Osaka, Japan) containing 5% fetal bovine serum (ICN Biomedicals, Irvine, CA, USA) for 36 h at 37 ◦C with 5% CO2. Each disk specimen was immersed into 10 mL of culture solution for 24 h and then 100 μL of the solution was added to each 96-well plate, followed by 24 h incubation. Finally, the absorbance of each well at 450 nm was recorded using a microplate reader (model Infinite F200; Männedorf, Switzerland) (*n* = 10).
