Two Dimensional Correlation Analysis of Raman microspectroscopy of subcellular interactions of drugs in vitro
Abstract
Two dimensional correlation analysis is explored to data mine the time evolution of the
characteristic Raman microspectroscopic signatures of the subcellular responses of the
nucleoli of human lung cancer cells to the uptake of doxorubicin. A simulated dataset of
experimental control spectra, perturbed with systematically time-dependent spectral changes,
constituted by a short term response which represents the initial binding of the drug in the
nucleolus, followed by a longer term response of the organelle metabolism, is used to validate
the analysis protocol. Applying two dimensional correlation analysis, the in phase,
synchronous correlation co-efficients are seen to contain contributions of both response
profiles, whereas they can be independently extracted from the out of phase, asynchronous
correlation co-efficients. The methodology is applied to experimental data of the uptake of
doxorubicin in human lung cell lines to differentiate the signatures of chemical binding and
subsequent cellular response.