Table 2.

Schematic representations of the reviewed incorporation strategies and their resulting growth factor release profiles

Incorporation strategy	Schematic	Release profile [72]	Advantages (+) and limitations (−)
Covalent binding			+ No GF diffusion out of scaffold − Loss of GF bioactivity
Physical entrapment/ Adsorption			+ GF bioactivity maintained − Diffusion and degradation mediated release − Rapid burst release − Difficult to control release rate
Incorporation into micro/nanospheres			+ Better control of GF release rate + Possibility for sequential release of multiple GFs − Additional fabrication steps − Can rely on use of harsh chemicals

 = covalent bond;  = growth factor;  = micro/nanocapsule.