Fig. 6

Effect of ZNGs treatment on P. aeruginosa cells from FTIR spectroscopy. a Dried samples: comparison between the untreated (UT) sample FTIR spectrum (black line) and the treated sample one (red line) in the 1800–1300 cm⁻¹ spectral range. The difference between the two spectra is also reported (green line). Data relative to the 1300–900 cm⁻¹ are shown in the inset. b Liquid samples (D₂O solution): comparison between the untreated (UT) sample FTIR spectrum (black line) and the treated sample one (red line) in the 1800–1300 cm⁻¹ spectral range. For the purpose of comparing the shape of different spectra, data were scaled with respect to the low wavenumbers side of the Amide II band (~1543 cm⁻¹) in the case of dried samples or the Amide IIʹ band (~1450 cm⁻¹) in the case of deuterated liquid samples