Probing oxidative stress in single erythrocytes with Raman Tweezers

Raman Tweezers have been successfully applied to characterize chemically-induced oxidative stress on optically-trapped live, single erythrocytes. There is significant enhancement in Raman peak intensities corresponding to SS and C–S stretching modes that are induced by oxidative stress. This is consistent with the formation of mixed disulphides between protein SH groups and low-molecular-mass thiols such as glutathione during oxidative damage to cells. Enhancement in glutathione level as a protective response against oxidative stress has been observed. Principal component analysis of the data yields good discrimination between spectra of normal and stress-induced red blood cells.