Document Type

Article

Rights

This item is available under a Creative Commons License for non-commercial use only

Disciplines

Biophysics, Medicinal chemistry, Other clinical medicine subjects, Health-related biotechnology

Publication Details

Analyst, 136, 2450-2463 (2011)

Abstract

Confocal Raman Micro spectroscopy (CRM) is employed to examine the chemical and physiological effects of anticancer agents, using cisplatin and A549 adenocarcinoma cells as a model compound and test system respectively. Spectral responses of the membrane and cytoplasm of the cell are analysed independently and the results are compared to previously reported spectroscopic studies of the nucleus. Moreover, Raman spectra from the proteins extracted from the control and exposed samples are acquired and analysed to confirm the origin of the molecular changes of the cell membrane and cytoplasm of the A549 cells. Multivariate data analysis techniques including Principal Component Analysis (PCA) and Partial Least Square Regression (PLSR) along with PLS-Jack knifing are used to analyse the data measured from the cell membrane and cytoplasm of the A549 cells and results are correlated with parallel measurements from the cytotoxicity assay MTT. A PLSR model is used to differentiate between the chemical effect of the chemotherapeutic agent and the physiological response of the A549 cells and to identify regions of the spectrum that are associated with these processes respectively. The PLSR model is also employed to predict, on the basis of the Raman spectra, the effective dose as well as the level of physiological response, using spectra data from the cytoplasmic and cell membrane regions. The effectiveness of the models based on spectral datasets from the cell membrane and cytoplasm is compared to similar models constructed using spectral data from the nuclear region as well as one combining spectral data from all regions. In all cases, higher prediction accuracy is found for regression against the cisplatin dose, and for both regression against dose and physiological response, nuclear data yields higher precision.