Figure 7.

Sulfonation treatment of PEEK surface. (a) Sang et al. compared the biological properties of untreated PEEK (PEEK), sulfonated PEEK (SPEEK), and sulfonated PEEK coated with SrCO₃-poly(dopamine) + gentamicin-silk protein (n + silk, where n defines the concentration of SrCO₃-poly(dopamine), i.e., 0.08 mg/mL, 0.16 mg/mL, and 0.32 mg/mL, respectively). Left: in vitro antibacterial zone inhibition tests. Right: in vivo osteogenesis as imaged using µCT [138]. (b) Biological properties of untreated PEEK (PK), mildly sulfonated PEEK (SPK), and SPK layered with poly(dopamine) and loaded with moxifloxacin hydrochloride and growth peptide (SPD-MOX/OGP). Paa = antibacterial percentage of adherent bacteria. Pap = antibacterial percentage of planktonic bacteria. * p < 0.05 [140]. All figures were re-printed with permission from the literature [138,140].