Burhol P G, Jorde R, Florholmen J, Jenssen T G, Vonen B
Scand J Gastroenterol. 1985 May;20(4):466-9. doi: 10.3109/00365528509089682.
A systematic approach is outlined for the preparation of a whole series of immunoreactive 125I-labeled gastrointestinal regulatory peptides with high specific radioactivities. In our hands, the theoretically superior Iodo-gen method has no more to offer than the harsher chloramine-T method in the iodination of secretin, vasoactive intestinal polypeptide, gastric inhibitory polypeptide, and motilin; whereas the gentler Iodo-gen method has to be used to obtain fully immunoreactive cholecystokinin39 (CCK39) and Tyr1-somatostatin tracers. By applying the iodination mixtures on a Sephadex G-15 or a Sephadex G-10 column followed by an SP Sephadex C-25 column--being eluted under so-called 'finite adsorption equilibrium' between the peptides to be purified and the adsorbent--highly purified tracers are obtained with unusually high specific radioactivities. Stored at -20 degrees C in diluted aliquots of from 200 to 500 microliter, these tracers can be used for radioimmunoassay purposes without rechromatography for at least 60 days.
本文概述了一种系统方法，用于制备一系列具有高比放射性的免疫反应性125I标记的胃肠调节肽。在我们的实验中，理论上更优的碘代甘氨酸法在对促胰液素、血管活性肠肽、胃抑制多肽和胃动素进行碘化时，并不比更严苛的氯胺-T法更具优势；而对于胆囊收缩素39（CCK39）和酪氨酸1-生长抑素示踪剂，必须使用更温和的碘代甘氨酸法以获得完全免疫反应性的示踪剂。通过将碘化混合物应用于葡聚糖凝胶G-15或葡聚糖凝胶G-10柱，随后再应用SP葡聚糖凝胶C-25柱——在待纯化的肽与吸附剂之间的所谓“有限吸附平衡”下进行洗脱——可获得具有异常高比放射性的高度纯化示踪剂。将这些示踪剂以200至500微升的稀释分装形式储存在-20℃下，无需重新色谱分离，至少60天内可用于放射免疫测定。
