Fig. 3

Mechanism analysis of the binding between copolymer and MPPs. a, b AFM images of PNI-co-ATBA_0.2 film before (a) and after (b) treatment with a 4pS solution (concentration: 37.5 μmol L⁻¹ in Tris buffer at pH 7.4 and 20 °C) as well as the corresponding section profiles along the green lines. Scale bars: 2 μm. c Time-dependent dissipation curves of the copolymer film in response to the adsorption of various PP (1pS–4pS) and NMP (1–3), solution: CH₃CN/H₂O (v v⁻¹) = 4:1, pH = 7.4 at 20 °C. d CD spectra of 4pS upon additions of different (0–30) equimolar amounts of ATBA monomers in water. e Possible binding mode of 4pS with three ATBA monomers, obtained from quantum chemistry calculations, density function theory, at 6–31 G level of theory, solvent: water, temperature: 20 °C