Ramer · Alavi Nuclear Medicine Technology

82 Radioactivity, Radiopharmacy, and Quality Assurance25) Which of the following can be said regarding effectivehalf-life?a. it is always longer than the physical half-lifeb. it always shorter than both the physical and thebiologic half-lifec. it is always shorter than physical half-life, but longerthan the biologic half-lifed. it is always longer than the biologic half-life, butshorter than the physical half-life26) The purpose of adding EDTA to sulfur colloid whenlabeling with 99m Tc is:a. to prevent aggregation of sulfur colloidb. to bind excess Al 3+c. to prevent loss of the radiolabeld. a and b onlye. b and c only27) A diphosphonate kit should generally be used withinhow many hours after preparation?a. 2 hoursb. 4 hoursc. 6 hoursd. 24 hours28) What is the usual particle size of sulfur colloid?a. 0.3–1.0 µmb. 0.03–0.1 µmc. 2.0–10 µmd. 4.0–15 µm29) Which radiopharmaceutical, when correctly prepared,will have the smallest particle size?a. 99m Tc sulfur colloidb. 99m Tc albumin colloidc. 99m Tc human serum albumind. 99m Tc macroaggregated albumin