UV Resonance Raman Study of Apoptosis, Platinum-Based Drugs, and Human Cell Lines.

Abstract

As a noninvasive molecular analysis technique, ultraviolet resonance Raman (UVRR) spectroscopy represents a label-free method suitable for characterizing biomolecules. Using UVRR spectroscopy, we collected spectral fingerprints of UV absorbing cellular components, including proteins, nucleic acids, and unsaturated lipids. This knowledge was used to guide the assignment of spectra derived from intact human cell lines (i. e., HSC-3 and HaCaT) and from the apoptotic events induced by cisplatin. Notably, a jet-flow system was employed to generate flowing cell suspensions during UVRR measurements, minimizing UV-induced damage. A spectral marker is established based on the ratio of Raman intensities at 1488 and 1655 cm-1 ; this ratio correlates to the level of cell death due to apoptosis. Collectively, this work demonstrates that UVRR spectroscopy is a sensitive and informative probe of cellular physiology and molecular composition. The molecular insight obtained from UVRR measurements can be used to improve understanding of therapeutic treatment and to guide drug development and the choice of therapeutic agents.