Chemometrics-Enabled Raman Spectrometric Qualitative Determination and Assessment of Biochemical Alterations during Early Prostate Cancer Proliferation in Model Tissue

Figure 6

Principal component loadings that explain natural grouping of PNT1a and PC3 scores due to (a) PC5 (0.03%) for stage 1, (b) PC8 (0.02%) for stage 2, and (c) PC5 (0.01%) for stage 3 datasets. The loadings profiles are noted to contain useful peaks amid noisy features. The useful peaks (weak Raman bands) were extracted from the raw loading profiles by adjustment of threshold and sensitivity levels/parameters in peak finding function in Omnic® software from Thermo Scientific. Sensitivity levels were set at a low value (30%) so that noise and other unimportant features above threshold value were eliminated.

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