Raman spectroscopy--a potential platform for the rapid measurement of carbon nanotube-induced cytotoxicity.

In this study the suitability of Raman spectroscopy for the determination of carbon nanotube mediated toxicity on human alveolar carcinoma epithelial cells (A549) is explored. The exposure of this cell line represents the primary pathway of exposure in humans, that of inhalation. Peak ratio analysis demonstrates a dose-dependent response which correlates to previous toxicological studies. Principal component analysis is employed to further classify cellular response as a function of dose and to examine differences between spectra as a function of exposed concentration. To further illustrate the potential of Raman spectroscopy in this field, Partial Least Squares (PLS) regression and genetic algorithm feature selection have been utilised to demonstrate that clonogenic endpoints, and therefore toxic response, can be potentially predicted from spectra of cells exposed to un-determined doses, removing the need for costly and time consuming biochemical assays. This preliminary study demonstrates the potential of Raman spectroscopy as a probe of cytotoxicity to nanoparticle exposure.