Rituximab的碘标记方法及其正常小鼠体内的生物分布

系统考察了反应时间、NBS 用量、反应温度、反应体积、pH值等条件对125I-Rituximab标记率的影响。用ITLC-SG测定标记物的标记率或放化纯度。在最佳条件下，标记率大于92％。用体外结合试验测定储存不同时间的131I-Rituximab的免疫活性，证明随着131I-Rituximab的储存时间增加免疫活性下降。正常小鼠静脉注射131I-Rituximab后体内分布显示血液中放射性分布较高，并可持续6天，表明131I-Rituximab体内稳定。异常毒性试验结果表明131I-Rituximab毒性低。

Iodination Conditions of Rituximab and Its Biodistribution in Animal

The effects of reaction time, amount of the NBS, reaction temperature, volume and pH on the labeling efficiency of 125I-Rituximab were systematically studied. The labeling efficiency is more then 92% under the optimum labeling conditions. The labeling efficiency was detected by ITLC-SG. Binding test between Raji cells and 125I-Rituximab were carried out. The results demonstrated that the binding of 131I-Rituximab and Raji cells was time dependent. The biodistribution in mice was detected. High distribution of radioactivity that lasted for 6 days was detected in blood after injection of 131I-Rituximab. It indicate the stability of 131I-Rituximab in vivo. The acute toxicity of the 131I-Rituximab is low.