To study PHIP-polarized fumarate as a probe of cellular necrosis, experiments were performed in which the reaction mixture containing hyperpolarized [1-13 C]fumarate was added to cell suspensions. Three experiments were performed; one in which the cell media contained 10 million lysed EL-4 tumour cells, one with 10 million intact (healthy) EL-4 tumour cells, and one with no cells in the media. In these experiments, after perfusion of the [1-13 C]fumarate containing solution through the cells suspension, the 13 C NMR signal was acquired every 2 s using 15° flip-angle pulses, so as to probe the metabolism over time without significantly perturbing the magnetization.