Elliott M, Goodfriend T L
J Nucl Med. 1980 Aug;21(8):738-40.
The counting efficiency of iodine- 125 in well-type scintillation counters is reduced when the labeled compound is dissolved or suspended in chlorinated hydrocarbons or potassium iodide solution. The reduction is probably caused by absorption of the weak gamma and x-rays of I- 125 by the halogen atoms in the solvent or solute molecules. This phenomenon may introduce artifacts into procedures involving radioiodinated compounds and organic solvents and KI, but it could also be useful in differentiating bound from free labeled ligands by their differential solubility (and attenuation) in dense solvents. The reduction in counting efficiency can be overcome by evaporation of the solvent, or by the use of emitters with higher energy radiation.
当标记化合物溶解或悬浮于氯代烃或碘化钾溶液中时，井型闪烁计数器中碘 - 125的计数效率会降低。这种降低可能是由于溶剂或溶质分子中的卤素原子对I - 125的弱γ射线和X射线的吸收所致。这种现象可能会在涉及放射性碘化化合物、有机溶剂和KI的程序中引入假象，但它也可用于通过标记配体在浓溶剂中的不同溶解度（和衰减）来区分结合态和游离态。计数效率的降低可以通过溶剂蒸发或使用具有更高能量辐射的发射体来克服。
