Fig. 3

a False colour map of peak due to ring breathing (associated with cytochrome, signal integrated between 740–760 cm⁻¹) in cryosection of murine liver tissue. Regions of low peak signal intensity are marked in red, while regions of high intensity are marked in yellow. Raman spectra were acquired with a 532 nm laser at 6 mW power, 3 s exposure and 1 μm resolution using a 50× air objective. False colour scale bar of signal-to-baseline intensity (arbitrary units) is shown to the right of the map. b Example Raman spectrum from the acquired map