Nakazawa N, Maki K, Ogawa H, Ikeda O
Radioisotopes. 1977 Feb;26(2):80-5. doi: 10.3769/radioisotopes.26.2_80.
125I-labelled human-C-peptide was prepared by chloramin T method, enzymic method and active ester method, respectively. Using respective 125I-labelled human-C-peptides in human proinsulin-C-peptide RIA, we compared the binding (Bo/T%) to antibody, displacement by standard human-C-peptide, the recovery test and stability. The usable 125I-labelled antigen for human proinsulin-C-peptide RIA could be prepared by chloramin T method and enzymic method wich labelled 125I to tyrosyl human proinsulin connecting peptide, and active ester method which conjugates 125I-labelled active ester to human proinsulin connecting peptide. The differences among those 125I-labelled antigens was not observed in displacement (B/Bo%) by standard human-C-peptide and the recovery test. In the case of constant preparation of 125I-labelled antigen for RIA, the enzymic method was the best from the viewpoint the reaction ratio is stable and stability of Bo/T% is good.
分别采用氯胺T法、酶法和活性酯法制备了125I标记的人C肽。在人胰岛素原-C肽放射免疫分析中使用各自的125I标记的人C肽，我们比较了与抗体的结合（Bo/T%）、标准人C肽的置换、回收率测试和稳定性。用于人胰岛素原-C肽放射免疫分析的可用125I标记抗原可通过将125I标记到酪氨酰人胰岛素原连接肽的氯胺T法和酶法，以及将125I标记的活性酯与人胰岛素原连接肽偶联的活性酯法制备。在标准人C肽的置换（B/Bo%）和回收率测试中未观察到这些125I标记抗原之间的差异。在为放射免疫分析持续制备125I标记抗原的情况下，从反应率稳定且Bo/T%稳定性良好的角度来看，酶法是最佳方法。
