Fig. 1

Metabolic profiling of hUC-MSC lysates by SERS. a Workflow of hUC-MSC metabolome-transcriptomic analysis. b Bright-field images of hUC-MSCs (scale bar: 200 μm) and the SERS metabolic profiling of the corresponding cell lysates. For each lysate sample, a spectral set comprising 200 spectra were measured as displayed by the heatmaps. The mean spectra are provided for clarity. c The relative cell number, d The cell viability, e the passaging number, and f the expansion rate has been recorded along the 14-day culture. For each cell origin, the data are displayed by the mean values from three biological replicates. Error bar: standard deviation (n = 3). g Absorbance spectrum and h the hydrodynamic diameter of citrate-reduced Ag NPs. i Pearson’s correlation coefficients among the mean SERS spectra obtained from the C1-originated hUC-MSC lysates of different generations (P2, P6 and P10) and different biological replicates (S1, S2 and S3). j Pearson’s correlation coefficients among the mean SERS spectra obtained from the hUC-MSC lysates of different generations (P2, P6 and P10) and origins (C1, C2 and C3). k 2D t-SNE visualization of all the SERS spectra and l the highlighted t-SNE distribution of the SERS spectra obtained from the C1-originated hUC-MSC lysates.