Page 38 - Read Online

Liu et al. J Cancer Metastasis Treat 2019;5:4 I http://dx.doi.org/10.20517/2394-4722.2018.55 Page 5 of 14

Figure 2. A set of typical resonance Raman raw spectra collected from a horizontal section of normal human skin sample, and a vertically
sliced BCC skin sample measured at different depths. (Top), the spectrum was from dermis layer of normal skin showing nine feature
peaks; (middle), the spectrum was from the vertically sliced BCC sample at a depth of 100 µm. There are eight characteristic peaks
-1
-1
-1
-1
including increased peaks at 753 cm and 1,589 cm , but intense carotenoids peaks at 1,161 cm and 1,521 cm disappeared compared to
the normal tissue (top); (bottom), the spectrum was from BCC sample at a depth of 1,100 µm, substantially similar to the depth of 100 µm,
-1
-1
with six Raman peaks, but carotenoids peaks at 1,161 cm and 1,521 cm are present and obviously weaker than normal tissue sample (top).
-1
-1
Those peaks of 753 cm and 1,589 cm greatly decreased in comparison with the depth of 100 µm. BCC: basal cell carcinoma
a spot diameter of 1 µm and the power of the beam at the sample position was kept at 3.5 mW. RR spectra
were collected using a one-second integration time and 30 accumulations, with a system resolution down to
-1
the optical diffraction limit of ~200 nm. The spectra were collected over the spectral range of 400-4000 cm .
-1
The spectral resolution was 2 cm in the range of interest [41,42] . All the spectra were collected at ambient
room temperature. Student’s t-test was used to determine if particular RR peak intensities between normal
and BCC samples were significantly different.