OBJECTIVE Given the requirements of high sensitivity and spatial resolution, the development of new positron emission tomography (PET) agents is required for PET renography. The objective of this study was to investigate a new fluorine-18 labeled hippurate analogue of picolinamide, N-(6-[18F]Fluoropyridin-3-yl)glycine, as a new renal PET agent for evaluating renal function. METHODS N-(6-[18F]Fluoropyridin-3-yl)glycine was prepared via a two-step reaction, including the nucleophilic substitution reaction of Br with 18F using methyl 2-(6-bromonicotinamido)acetate as a precursor followed the hydrolysis with sodium hydroxide and purification by preparative-HPLC. The in vitro and in vivo stability were determined using HPLC, and the plasma protein binding (PPB) and erythrocyte uptake of N-(6-[18F]Fluoropyridin-3-yl)glycine were determined using blood collected from healthy rats at 5 min post-injection. Biodistribution and dynamic micro-PET/CT imaging studies were conducted in healthy rats. RESULTS N-(6-[18F]Fluoropyridin-3-yl)glycine was prepared within 45 min with an uncorrected radiochemical yield of 24.5 ± 6.7% (n = 6, based on [18F]F-) and a radiochemical purity of >98%. N-(6-[18F]Fluoropyridin-3-yl)glycine demonstrated good stability both in vitro and in vivo. The results of the biodistribution and dynamic micro-PET/CT imaging studies in normal rats indicated that N-(6-[18F]Fluoropyridin-3-yl)glycine was rapidly and exclusively excreted via the renal-urinary pathway. CONCLUSION N-(6-[18F]Fluoropyridin-3-yl)glycine is has been shown to be a promising renal PET agent and warrants further evaluation of renal function.

中文翻译：

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N-（6- [18F]氟吡啶吡啶-3-基）甘氨酸的合成作为潜在的肾脏PET药物。

目的鉴于高灵敏度和空间分辨率的要求，PET肾盂造影需要开发新的正电子发射断层扫描（PET）剂。这项研究的目的是研究一种新的氟18标记的吡啶甲酸酰胺的马尿酸盐类似物N-（6- [18F]氟吡啶并-3-基）甘氨酸，作为评估肾功能的新型肾脏PET药物。方法通过两步反应制备N-（6- [18F]氟代吡啶-3-基）甘氨酸，包括以2-（6-溴代烟酰胺基）乙酸甲酯为前体，Br与18F进行亲核取代反应，然后水解用氢氧化钠洗涤，并通过制备型HPLC纯化。使用HPLC测定体外和体内稳定性 并在注射后5分钟使用健康大鼠的血液测定N-（6- [18F]氟吡啶吡啶-3-基）甘氨酸的血浆蛋白结合（PPB）和红细胞摄取。在健康大鼠中进行了生物分布和动态micro-PET / CT成像研究。结果N-（6- [18F]氟吡啶吡啶-3-基）甘氨酸在45分钟内制备，未经校正的放射化学产率为24.5±6.7％（基于[18F] F-，n = 6），放射化学纯度> 98％。N-（6- [18F]氟代吡啶-3-基）甘氨酸在体外和体内均表现出良好的稳定性。在正常大鼠中的生物分布和动态micro-PET / CT成像研究结果表明，N-（6- [18F]氟吡啶并-3-基）甘氨酸可以通过肾脏泌尿途径快速排泄。