ADSL and bacterial infectious disease: pMAA swelled in pH ≈ 7.4 (physiological environment without bacterial infection), preventing the abrupt release of AMPs and thus mitigating cytotoxicity; in contrast, PMAA in pH ≤ 6.0 (acidic microenvironment produced by bacterial infection) disintegrates and rapidly releases AMPs showing powerful bactericidal activity (Chen X et al., 2020).