123I的制备及其标记新型小分子融合肽的初步研究

摘要

123I with radioactivity of 11.1 TBq/(A·h) and nuclear purity of more than 98. 6% was prepared in the CS-30 cyclotron of Sichuan University via 121 Sb(α,2n)123I nuclear reaction by α-energy of 26.5 MeV and using Sb target of 62.2-64.3 mg/cm2. Furthermore, VhCDR1-VhFR2-VlCDR3, a new fusion peptide was labeled with 123I, and in vitro and in vivo of the labeled peptide was evaluated. The results show that the labeling yield of 123I-VHCDR1-VHFR2-VLCDR3 is more than 90%. The deiodination of 123I labeled VH CDR1-VHFR2-VLCDR3 in vivo is minimal, and 123I-VHCDR1-VHFR2-VLCDR3 has a high stability in vitro.%本工作利用天然锑靶,通过121 Sb(α,2n)123I核反应,在控制锑靶厚度为62.2～64.3 mg/cm2和α粒子能量为26.5 MeV的情况下,可以得到11.1TBq/(A·h)以上且核纯度高达98.6％的123I.利用制备的123I进行了小分子融合肽拟似物VH CDR1 -VH FR2 -VL CDR3的123I标记,并对标记物的体外稳定性及在正常小鼠体内的分布进行了初步研究.结果表明,123I标记VH CDR1 -VH FR2-VL CDR3的标记率可达90％00以上,123I标记物在体内不易脱碘且具有较高的体外稳定性.