The clearance of Rh-BLM in vivo followed biphasic kinetics, as illustrated in Figure 6. The initial rapid phase showed 90% of the injected dose cleared from the body within 24 h, followed by Cathepsin G further 2–5% of the injected dose clearing in the following 24 h. At 48 h, only 5% of the injected dose could be accounted for in the faeces; most of the material had been cleared in the urine. By contrast, 105Rh chloride when injected was retained in the animals. Only 20% of the material was excreted in a monophasic fashion over a 48-h period. The excretion through faeces appeared similar to that of complex, with approximately 6% being lost in 48 h. Biodistribution of the Rh-BLM complex and free metal at 48 h is shown in Figure 7. The retention of 105Rh chloride in the tissues collected was found to be approximately 100-fold greater than 105Rh-BLM in corresponding samples. The only exception was in the kidneys, where the levels of free metal were approximately three times higher than those for 105Rh-BLM complex.