Pimm M V, Perkins A C, Hudecz F
Cancer Research Campaign Laboratories, University of Nottingham, UK.
Eur J Nucl Med. 1992;19(6):449-52. doi: 10.1007/BF00177374.
There is a growing interest in the use of macro-molecular carriers for therapeutic agents. If these carriers can be labelled with an appropriate gamma-emitter, their biodistribution could be followed by scintigraphy. We have imaged the biodistribution of a synthetic branched polypeptide, based on a poly-L-lysine backbone (average molecular mass 45 kDa). The polymer was conjugated to diethylene triamine penta-acetic acid and labelled by chelation with indium-111. Mice were injected i.v. with labelled material and imaged with a gamma-camera with a pin-hole collimator. Images showed the majority of tracer remaining in the blood pool, but about 35% appeared in the urinary bladder within 1.5 h. When the 111In-polymer was fractionated by gel filtration chromatography on S-300, the imaging showed that the early eluting material was retained, the intermediate showed some renal clearance, and the late was rapidly excreted. These findings show the value of gamma-scintigraphy for biodistribution studies with such polymeric drug carriers and its potential for clinical pharmacokinetic studies.
人们对将大分子载体用于治疗剂的兴趣日益浓厚。如果这些载体能用合适的γ发射体进行标记，那么它们的生物分布就可以通过闪烁扫描法进行追踪。我们已经对一种基于聚-L-赖氨酸主链（平均分子量45 kDa）的合成支链多肽的生物分布进行了成像。该聚合物与二乙烯三胺五乙酸偶联，并通过与铟-111螯合进行标记。给小鼠静脉注射标记物质，并用带有针孔准直器的γ相机进行成像。图像显示大部分示踪剂保留在血池，但约35%在1.5小时内出现在膀胱中。当111In-聚合物在S-300上通过凝胶过滤色谱法进行分级分离时，成像显示早期洗脱的物质被保留，中间部分显示出一些经肾脏清除，而后期的则迅速排出。这些发现表明γ闪烁扫描法在这类聚合物药物载体生物分布研究中的价值及其在临床药代动力学研究中的潜力。
