Figure 5.

(a) Injection and self-healing of the cell-laden GC/DF PEG hydrogel (A, A1 and A2), and the optical microscopy (B and B1) and fluorescent images (C and C1) of the embedded cells on 1st and 7th day culture, respectively. B2 and C2 are the 4 times magnification of the red squares in image B1 and C1, respectively. The red arrows indicate the cell divisions; (b) cell numbers in a series of hydrogels with different mass fractions of DF-PEG at denoted time after injection. ‘2% + 2%’ refers to a hydrogel containing 2% DF-PEG and 2% PEG without aldehyde groups, which contained the same mass of PEG as the hard hydrogel (4%), while the modulus was similar to that of the medium hydrogel (2%). Data represent mean ± SD (n = 3, *: p < 0.05). Reprinted with permission [40]. Copyright 2017, Elsevier Ltd.