Here, we describe an extension of our silicon fluoride acceptor (SiFA) protocol for ¹⁸F-labeling of peptides that addresses challenges associated with preparing a clinical-grade (Tyr³)-octreotate (TATE) tracer for diagnosis of neuroendocrine tumors (NETs). After several iterations of protocol optimization (e.g., finding the optimal pH at which the isotopic exchange (IE) reaction produces high radiochemical yields (RCYs)), the SiFA technology achieved clinical applicability, as showcased by radiosynthesis of [¹⁸F]SiFAlin-TATE ([¹⁸F]SiTATE), the first SiFA peptide used in the clinical diagnosis of NETs. The TATE peptide binds to somatostatin receptors associated with NETs. Radiolabeled TATE derivatives are routinely applied in clinical oncological PET imaging. The (SiFA) ¹⁸F-labeling technology is based on the IE of a ¹⁹F atom for a radioactive ¹⁸F atom, a highly efficient labeling reaction under mild conditions. The ¹⁹F is part of a biomolecule bearing the SiFA building block, composed of a central silicon (Si) atom, a ¹⁹F atom connected to the Si atom, and two Si-bound tert-butyl groups. The IE proceeds through a penta-coordinate bipyramidal intermediate, followed by elimination of non-radioactive ¹⁹F, yielding the labeled compound in high RCYs at room temperature (22 °C). The simplicity and lack of side-product formation of this approach enable a one-step, kit-like preparation of structurally complex and unprotected radiopharmaceuticals. Compounds such as peptides used for tumor imaging in nuclear medicine can be ¹⁸F-labeled without the need for complex purification protocols. [¹⁸F]SiTATE can be synthesized within 30 min in preparative RCYs of 42%, radiochemical purity of >97% and high molar activity of 60 GBq/µmol.

在这里，我们描述了我们的氟化硅受体 (SiFA) 协议的扩展，用于¹⁸ F-标记肽，解决了与制备用于诊断神经内分泌肿瘤 (NET) 的临床级 (Tyr ³ )-奥曲酸 (TATE) 示踪剂相关的挑战. 经过多次方案优化迭代（例如，找到同位素交换 (IE) 反应产生高放射化学产率 (RCY) 的最佳 pH 值），SiFA 技术实现了临床适用性，如 [ ¹⁸ F]SiFA lin-泰特 ([ ¹⁸F]SiTATE)，第一个用于 NET 临床诊断的 SiFA 肽。TATE 肽与 NET 相关的生长抑素受体结合。放射性标记的 TATE 衍生物通常用于临床肿瘤 PET 成像。(SiFA) ¹⁸ F 标记技术基于¹⁹ F 原子对放射性¹⁸ F 原子的 IE，这是一种在温和条件下的高效标记反应。¹⁹ F 是带有 SiFA 结构单元的生物分子的一部分，由中心硅 (Si) 原子、连接到 Si 原子的19 F 原子和两个 Si 结合的^叔丁基组成。IE 通过五坐标双锥体中间体进行，然后消除非放射性¹⁹ F，在室温 (22 °C) 下产生高 RCY 的标记化合物。这种方法的简单性和无副产物形成使得结构复杂且无保护的放射性药物的一步、类似试剂盒的制备成为可能。核医学中用于肿瘤成像的肽等化合物可以进行¹⁸ F 标记，而无需复杂的纯化方案。[ ¹⁸ F]SiTATE 可在 30 分钟内合成，制备 RCY 为 42%，放射化学纯度 >97%，摩尔活性为 60 GBq/µmol。