Figure 3

(A) Brightfield image of OvCa429 cells on the surface of MCA treated with LPA correlates with (B) the CARS image of −2930 cm⁻¹ peak area. (C) The maximum intensity CARS spectrum and average spectrum of the map show varying contributions of CH₂ and CH₃ signal. The spontaneous Raman spectrum obtained from LPA treated OvCa429 cells is plotted over the equivalent Raman shifts for comparison (See Fig. S3 for more details). (D) The nonlinear peak fit (orange) of the CARS intensity (black) is composed of nonresonant background (green) and resonant contributions from −2850 cm⁻¹ (red) and −2930 cm⁻¹ (blue) vibrational bands, respectively. (E) The frequency scatter plot displays overlapping spectral clusters with 95% confidence ellipses and angle, φ, corresponding to the spectral separation of lipids (red) and proteins (blue). (F) The reconstructed map shows the chemical distribution of the segmented lipid (red) and protein (blue) pixels. Experimental parameters: Pump = 720 nm, 26.50 mW; Supercontinuum = 785–945 nm, 3.70 mW; Acquisition time = 500 ms/pixel; Map size = 51 × 51 pixels; Steps = 300 nm; Objective = 100x, 0.9 NA.