FIG. 3.

(a) Principal component analysis of Raman spectra averaged in the cytosol region of individual images. Each spectrum was preprocessed by second derivative followed by mean centering. The symbols represent cells in specific culture conditions as follows: blue squares—OS, green cross-stars—BA, and red triangles—AD. The dashed ellipse indicates 95% confidence of the grouping boundaries. (b) Bottom Panel: Second derivative spectra of cytosol regions from AD, OS, and BA samples. Top Panels: Differences in the second derivative spectra between BA and the other two cultures, as indicated. The ordinate scale is a.u. Color images available online at www.liebertpub.com/tec