Figure 4

(A) Brightfield image of cellular shedding from LPA-treated OvCa429 sample has (B) corresponding CARS image of −2930 cm⁻¹ peak area. (C) The maximum intensity CARS spectrum and average spectrum of the map show similar chemical composition as cell surface of non-treated OvCa429 samples. The spontaneous Raman spectrum obtained from the LPA induced sheddings from OvCa429 cells is plotted over the equivalent Raman shifts for comparison (See Fig. S3 for more details). (D) The representative CARS spectrum and nonlinear peak fit results provide the resonant CH₂ and CH₃ components used for (E) the frequency scatter plot separating the chemical contributions 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.