Spectrum analysis of MNT-1, TPC2 and TYR knocked down MNT-1 using confocal Raman spectrum microscope. A−C) SE-ADM images of TPC2 knocked down MNT-1 cells at 1500 × , 5000 × and 10,000 × magnifications with an 7 kV EB. Increased number of melanosomes compared to parent MNT-1 cells were observed. D−F) SE-ADM images of TYR knocked down MNT-1 cells at 2000 × , 5000 × and 10,000 × magnifications. In the TYR knocked down MNT-1 cells black particles completely disappeared. G) An optical microscopic image of living MNT-1 cells. H) A 2D Raman image of the blue square in (G) at the carbon peak of 1372 cm-1 by 0.2 mW laser intensity and 50 ms measurement time at each pixel. I) A 2D Raman image at the carbon peak of 1584 cm-1. J) Raman spectra of the high carbon peak of MNT-1 indicated by a white arrow of (H) and (I). Clear peaks at 1372 and 1584 cm-1 were detected which corresponded to the reported melanin peak. K) An optical microscopic image of TYR knocked down living MNT-1 cells. L) A 2D Raman shift image of the blue square in (K) at the carbon peak of 1372 cm-1. The laser intensity was 0.2 mW. M) A 2D Raman shift image at the carbon peak of 1584 cm-1. No structures can be seen in the carbon peak images. N) Raman spectra at the centre of cell indicated by a white arrow of (L) and (M). O) Raman spectra at the centre of another cell at 2 mW laser intensity. In this plot, the lipid peak of 2909 cm-1 is clearly visible. Scale bars, 10 µm in (A, D, G, K), 2 µm in (B, E), 1 µm in (C, F) and 5 µm in (H, L).