“…After 10 h of growth under 37 °C, these samples showed a series of SERS peaks at 678 cm –1 ( v (CS) of methyl sulfide), 758 cm –1 (γ(CH) of aromatic ring), 1001 cm –1 ( v (CC) of aromatic ring), 1063 and 1123 cm –1 ( v (CO) of aldehyde or ketone), 1486 cm –1 ( v (CC) of aromatic ring), 1673 and 1684 cm –1 ( v (CO) of ketone and aldehyde), 2856, 2870, and 2912 cm –1 ( v (CH) of alkane), which indicated the presence of methyl sulfide, alkane, ketone, aldehyde, and aromatic compounds in their metabolites (Figure c,d). These results were consistent with those from mass spectrometry ,− and SERS measurements. , Furthermore, the intensities of the same SERS peaks were different among these samples. For instance, E.…”