Biochemical fingerprinting of dried blood serum from chronic lymphocytic leukemia patients by Raman spectroscopy: Towards prognostic classification

This study presents the application of micro-Raman spectroscopy to the serum of Chronic Lymphocytic Leukemia (CLL) patients for prognostic assessment, building upon preliminary identification by conventional methods. This label-free, rapid vibrational technique reveals distinct biochemical signatures that differentiate favorable from unfavorable prognoses, surpassing insights obtainable through morphology or immunophenotyping alone. Key spectral variations, notably at 1652 and 1205 cm^-1, linked to protein secondary structure and amino acid makeup, and the ratio between 1003 cm^-1 (phenylalanine) and 1344 cm^-1 (collagen) peaks, reflect metabolic changes correlating with disease progression. Integrating Raman spectra analysis with Principal Component Analysis (PCA) and Partial least squares (PLS) enabled accurate classification, highlighting micro-Raman's innovative potential as a complementary prognostic tool for CLL despite the complexity of spectral interpretation.