Fig. 4.

Hyperspectral stimulated Raman scattering (SRS) scan of hiPS- CM exposed to 48 hours hypoxia, covering the CH stretching Raman band (2800 - 3050 cm⁻¹) confirms association to lipid droplets. (a) SRS image at 2845cm⁻¹ (CH₂ symmetric stretching) characteristic of lipids. (b) Result of 3 endmember vertex component analysis (VCA). The red and blue show the normalized spectra of the 2 major endmembers retrieved. (c) Pseudo-colored VCA image of the SRS hyperspectral scan. The red spectrum is characteristic of lipids. It co-localizes with the lipid droplets observed in (a). The blue spectra have the features of the protein matrix that fills the cellular cytoplasm.