After this relatively short (pulsed) exposure to the drug(s), the cells were kept at 378 in drug-free medium for three more days, during which NMR spectra of the intact cells were recorded (at 3, 8, 24, 48 and 72 hr), whilst assessing the evolution of the apoptotic process and its extent on the basis of typical features, such as structural alterations of
cell nuclei (that became hypodiploid, with a condensed chromatin and DNA laddering), Annexin-V binding to the outer side of the cell membrane, cytochrome c release, caspase-3 activation and irreversible tochondrial embrane potential (DCm) loss.