Fig. 4: Muscle cell growth on different PC substrates.

a 3D chart of C2C12 cell proliferation rates within 3 days on the nanogrooved PC surfaces from different optical media, including the CD-R, DVD-R, and BD-R discs, and the flat PC substrate. b 2D diagram of curve fitting for the cell growth rates in a. Error bars represent the SD (n > 50,000 cells). c Average width, length, and elongation of myoblasts that grew on the corresponding PC substrates at 2 and 36 h after cell seeding. Error bars represent the SD (n = 400 cells). *P < 0.05, **P < 0.01, ***P < 0.001, compared to the flat PC substrate. Data are results from 3 independent experiments. Optical microscopic images of cell growth on flat and nanogrooved (groove width: 100 nm; ridge width: 200 nm; ridge height: 20 nm) PC substrates at different times after cell seeding: d 1 day, e 3 days