(A) Zeta potential of AuNC@PDA (squares) and
loading capacity of Dap (triangles) as a function of pH value. (B)
Release profiles of Dap upon irradiation by a diode laser at 808 nm
with a power density of 1.67 W/cm2 at a concentration of
0.4 nM AuNCs with different Dap loadings: 4 μg/mL or 6.2 ×
103 Dap molecules per AuNC (AuNC@DapLo/PDA,
squares) and 16 μg/mL or 2.5 × 104 Dap per AuNC
(AuNC@DapHi/PDA, diamonds). (C) Bacterial killing without
irradiation and treatment of (1) 2 μg/mL Dap, (2) 5 μg/mL
Dap, (3) AuNC@DapLo/PDA (4 μg/mL), and (4) AuNC@DapHi/PDA (16 μg/mL) and with irradiation (5) 2 μg/mL
Dap and (6) AuNC@DapLo/PDA (4 μg/mL, 2 μg/mL
released). Killing was assessed at 0 h (striped bars) and 24 h (solid
bars) post treatment. Black bars indicate non-irradiated groups, and
red bars indicate irradiated groups.