Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6.
Anal Chem. 2010 Nov 1;82(21):8961-9. doi: 10.1021/ac101901x. Epub 2010 Oct 12.
We describe the synthesis and characterization of metal-chelating polymers with a degree of polymerization of 67 and 79, high diethylenetriaminepentaacetic acid (DTPA) functionality, M(w)/M(n) ≤ 1.17, and a maleimide as an orthogonal functional group for conjugation to antibodies. The polymeric disulfide form of the DP(n) = 79 DTPA polymer was analyzed by thermogravimetric analysis to determine moisture and sodium-ion content and by isothermal titration calorimetry (ITC) to determine the Gd(3+) binding capacity. These results showed each chain binds 68 ± 7 Gd(3+) per chain. Secondary goat antimouse IgG was covalently labeled with the maleimide form of the DTPA polymer (DP(n) = 79) carrying (159)Tb. Conventional ICPMS analysis of this conjugate showed each antibody carried an average of 161 ± 4 (159)Tb atoms. This result was combined with the ITC result to show there are an average of 2.4 ± 0.3 polymer chains attached to each antibody. Eleven monoclonal primary antibodies were labeled with different lanthanide isotopes using the same labeling methodology. Single cell analysis of whole umbilical cord blood stained with a mixture of 11 metal-tagged antibodies was performed by mass cytometry.
我们描述了具有聚合度为 67 和 79、高二亚乙基三胺五乙酸 (DTPA) 官能度、M(w)/M(n) ≤ 1.17 的螯合聚合物的合成与表征，以及马来酰亚胺作为用于与抗体偶联的正交官能团。通过热重分析对 DP(n) = 79 DTPA 聚合物的聚合态二硫键形式进行分析，以确定水分和钠离子含量，并通过等温滴定量热法 (ITC) 确定 Gd(3+) 结合能力。这些结果表明每个链结合 68 ± 7 个 Gd(3+)。将二马来酰亚胺形式的 DTPA 聚合物（DP(n) = 79）与（159）Tb 共价标记了二级山羊抗小鼠 IgG。对该缀合物进行常规 ICPMS 分析表明，每个抗体携带平均 161 ± 4（159）Tb 原子。将此结果与 ITC 结果结合起来表明，每个抗体平均有 2.4 ± 0.3 个聚合物链连接。使用相同的标记方法，用不同的镧系元素同位素标记了 11 种单克隆原代抗体。通过质谱细胞术对用 11 种金属标记抗体混合物染色的整个脐带血进行单细胞分析。
