Radiopharmaceutical Half-life (t ½) Maximum beta (β) nergy in MeV (mean) Mean alpha (α) energy in MeV Mean gamma (γ) energy in keV Maximum tissue penetration (mean) Usual administered activity(SI units) Typical response time Typical response duration Retreatment interval Phosphorus [32P] 14.3 1.71 _ None 8 mm (3 mm) 5-10 mCi (185-370 MBq)       Strontium-89 [89SrCl2] (Metastron® 50.5 days (14 days biological T1/2) 1.46 (0.58) - none 5.5mm (2.4 mm) 4 mCi/kg (1.48 MBq/kg) 14-28 days 12-26 weeks >3months Samarium-153 [153Sm-EDTMP] (Quadramet®) 1.9 days 0.81 (0.22) - 103 2.5 mm (0.6 mm 1 mCi/kg 37 MBq/kg) 2-7 days 8 weeks >2months Radium-223 [223RaCl2] (Alpharadin®) 11.4 days - 5.64 - <0.1 mm 1.35kCi/kg (50 kBq/kg) <10 days Not established Not established Stannic-117 13. 6 days (conversion electron) - 159 0.2-0.3mm ~333 MBq 5-19 days 98 days Not established Rhenium-186 [186Re-HEDP} 3.8 days 1.07 (0.35) - 137 4.5 mm (1.1 mm) 35mCi (1295 MBq) 2-7 days 8-10 weeks >2months

Table 1: Physical characteristics of Bone seeking radiopharmaceuticals.