(A) Surface plasmon resonance (SPR) response analysis of the affinity between PN and BSA using BSA concentrations of 40–120 nmol/L. (B) Three-dimensional ligand–protein interaction mode for the binding site of BSA (PDB ID: 3V03) with the peptide. The active site residues are shown in cyan-colored stick form, the peptide is color-coded green, and the hydrogen-bond network with protein residues is represented as red dotted lines. (C) Continuous fluorometric assay of NFF-3 with (a) MMP-3, (b) MMP-2, and (c) MMP-9. (D) MALDI-TOF MS analysis of 4-arm-PEG10,000-MAL and PN-PEG (m/z). (E) Schematic representation of the construction of BSA MTN. MTN, micro-to-nano; BSA, bovine serum albumin; PN, BSA-binding MMP-3-responsive peptide; PEG, polyethylene glycol; NP, nanoparticle; AmB, amphotericin B; MMP, matrix metalloproteinase.