Preparation andBiodistribution of Myocardial Perfusion Imaging Agent 18F-TPT

⁹⁹Tc^m-sestamibi is typically used as amyocardial perfusion imaging agent for SPECT, however, the high uptake of liverand lung compromise the diagnostic accuracy. PET has higher spatial resolutionand quantitative measurement of myocardial tracer uptake. The lipophiliccationic compound, (4-[¹⁸F]fluorophenyl)triphenylphosphoniumion (¹⁸F-TPT)was synthesized as a potential positron emission tomography (PET) myocardialperfusion agent, biodistribution studies in the NH rats and Micro PET/CTimaging studies in the SD rats were performed. Total synthesis time was about 1h and the uncorrected synthesis yield was 2.5%, radiochemical purity was higherthan 99.5%, the product had good stability at room temperature. Biodistributiondata in rats showed high levels of accumulation in the heart with stableretention and rapid blood clearance, Heart-to-liver ratios at 30, 60, 90,and120 min were 33.1, 14.8, 25.7 and 17.3, respectively; Micro PET/CT imagingin the SD rat showed intense cardiac uptake and non-target tissues as liver,lung uptake were washed out quickly. The result show that ¹⁸F-TPT may have potential as amyocardial perfusion imaging agent for PET.     

18F标记多肽方法研究进展

随着正电子发射断层(Positron Emission Tomography,PET)显像技术在检测肿瘤、神经精神疾病和心脏疾病等方面的广泛应用,正电子核素18 F标记多肽作为PET示踪剂,近年来得到了快速发展,目前已有多种18F标记多肽的方法。本文以标记反应的特点,总结了以下七种18 F标记多肽的方法:1)18 F标记辅基法;2)固相标记法;3)18F-AlF络合标记法;4)点击化学法;5)18F-19F同位素交换法;6)芳香环亲电、亲核氟标法;7)其他标记法。并对各种方法的优缺点进行了比较。     

PET显像剂18F-FLT的合成条件优化

以MTR-Nos-Boc-LT（3-N-Boc-5-DMTr-3-Nos-2-脱氧-β-D-胸腺嘧啶核苷）为前体,利用季铵盐为相转移催化剂,采用质子溶剂,摸索更优的¹⁸FLT合成方法。并就合成的¹⁸FLT进行肿瘤鼠的MicroPET扫描。研究结果显示,季铵盐可以取代K_2.2.2/K₂CO₃体系,将QMA柱上的¹⁸F洗脱,并且是很好的相转移催化剂,氟化反应中加入质子溶剂,¹⁸FLT的放化纯度大于95%,不矫正合成效率为50%。     

99mTc标记新型硼酸结构快速心肌灌注显像药物的制备及初步显像评价

^99mTc-TEBO为临床批准的快速心肌灌注显像药物,该药物初始摄取高,但心肌滞留不稳定,为此,本研究通过优化其硼酸结构,分别制备标记物^99mTc-2SP、^99mTc-4LPA及^99mTc-2MDM,制备时间均为30 min,均为无色澄明液体,放化纯度均>95%,分别在健康小型猪体内进行SPECT动态显像,并与99mTc TEBO进行对比。结果表明：^99mTc-TEBO注射后0~5 min,左室心肌快速摄取,但随后心肌放射性迅速洗脱,在10 min时心肌约洗脱至峰值的75%,与心血池放射性浓度比值为1.63。^99mTc-2SP引入2-甲磺酰基吡啶-5-硼酸基后心肌初始摄取高,心肌滞留时间明显延长,心肌洗脱较缓慢,左室心肌均清晰显影,在第10 min时心肌摄取仍可保持峰值的95%,与心血池放射性浓度比值为3.75,明显高于^99mTc-TEBO。而另外两种显像剂^99mTc-4LPA和^99mTc-2MDM在注射后15 min内显像不理想。因此,^99mTc-2SP是有潜力的心肌灌注显像药物。     

新型心肌灌注显像剂99Tcm-CO-MIBI与99Tcm-MIBI的药理学比较

以犬为实验动物,     

18F标记非甾体类孕酮受体显像剂的制备

孕酮受体（PR）在乳腺癌中的水平可对乳腺癌的激素治疗进行预测和指导。5-［4-(3-氟丙基)-4-甲基-2-氧-1,4-二氢-2H-苯并［d］［1,3］口恶嗪-6-基］-1H-吡咯-2-甲腈（¹⁹FPr-Tanaproget）是Tanaproget的衍生物,它作为孕酮受体激动剂,对PR有高选择性和高亲和性,用放射性核素¹⁸F标记、正电子发射断层（PET）技术显像,可通过检测PR的情况,对乳腺癌进行诊断、治疗和预后评估。本实验以自制的氟标记前体,先合成了参比化合物¹⁹FPr-Tanaproget,再在氟多功能模块上合成了¹⁸FPr-Tanaproget,经Sep-Pak C-18柱和HPLC分离得到放化纯大于97%的产物。室温下在水中和血清中分别放置6h,放化纯仍大于95%。对标记率影响因素进行了优化,结果显示,最佳标记温度、时间、前体浓度分别为100℃、35min和32.7mmol/L,此条件下总的合成时间为45min,放化产率可达到10.9%（已校正）。     

18F标记氟甲基胆碱的半自动合成及其生物分布

利用^18F—FDG化学合成模块（CPCU）改装的半自动化多用氟标药物仪合成了氟甲基胆碱（^18F—FCH）,并进行了放射化学纯度测定、稳定性分析、生物分布、荷瘤小鼠显像以及安全性检验。利用半自动装置合成只需要55min,产率稳定,产品的放射化学纯度大于99％,体外稳定性良好。^18F-FCH的正常小鼠体内分布与文献报道的^11-CCholine相似,毒性较小。荷瘤小鼠显像结果表明,^18F—FCH可选择性地浓集于肿瘤细胞,是较好的肿瘤显像剂。     

Synthesis of 11C-CIC for PET Imaging of Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory neurodegenerative disorder of central nervous system. Imaging of myelin tracts in vivo would greatly improve the diagnosis and monitoring of MS. The ¹¹C-CIC was synthesized with¹¹C-CH₃-Triflate at high yields, and was confirmed by biodistribution and imaging. ¹¹C-CH₃-Triflate was distilled and trapped into a reaction vial containing the 2 mg precursor. The final production was purified by semi-HPLC to get¹¹C-CIC. The in vitro stability of¹¹C-CIC was studied at RT with or without Vc. The normal NH mice were sacrificed at different time after injection of¹¹C-CIC for biodistribution. The micro PET/CT was performed at 30 min post-injection. The radiochemical yield was 55% 65% decay corrected to¹¹CH₃-Triflate. The radiochemical purity was over 99% at specific activity of 60 GBq/μmoL. The HPLC showed the poor stability of¹¹C-CIC in vitro. The¹¹C-CIC was very stable after the 10 g/L Vc used as stabilizer. The initial uptake of the cerebrum was 2.78%ID/g. The radioactivity were excreted from the digestive system and urine. The micro PET/CT imaging showed good uptake in the cerebrum. The stability of¹¹C-CIC can be improved with Vc as stabilizer. The¹¹C-CIC was a candidate for imaging of myelin tracts for diagnosis or monitor MS.     

特异性前哨淋巴结显像剂99Tcm-rituximab药盒的制备及生物评价

采用2-巯基乙醇修饰Rituximab（利妥昔单克隆抗体）,制得其冻干药盒。所制得的冻干药盒性质稳定,可在-20 ℃冷冻保存3个月以上。利用⁹⁹Tc^m-葡庚糖酸钠（GH）交换法,标记冻干药盒得到⁹⁹Tc^m-rituximab,标记率和放化纯度均大于90%。生物分布结果显示：SD大鼠经前脚掌皮下注射⁹⁹Tc^m-rituximab后,前哨淋巴结的摄取值在1~4 h内逐渐增加,在4 h时达到（2.14±0.46）%ID,前哨淋巴结与注射点的放射性摄取比在4 h时达到最大（14.80%±2.11%）,且在18 h时,这一比值基本保持不变。SPECT显像结果表明,在30 min~18 h内,大鼠的前哨淋巴结清晰可见,无次级淋巴结显影。本研究提供了一种特异性前哨淋巴结显像剂的药盒化制备方法,该方法操作简便,性能稳定,便于在临床推广应用。     

Full Automated Synthesis of18F-FDOPA and Preliminary PET/CT Imaging

¹⁸F-fluoro-L-dihydroxyphenylalanine (¹⁸F-FDOPA) as a dopamine neurotransmitter imaging agent has been widely used for diagnosis and therapy evaluation of Parkinson's disease, brain tumors and neuroendocrine diseases with positron emission tomography (PET) imaging in clinical setting and research. To meet the increasing clinical demand in oncology and neurology, a routine protocol for the automated synthesis of¹⁸F-FDOPA with a disposable cassette system on an imported multifunctional synthesizer was studied and discussed.¹⁸F-FDOPA was automatically synthesized via a multiple-step reaction, including fluorination, reduction, iodization alkylation and hydrolysis, following purification by using a semi-preparative high-performance liquid chromatography (HPLC) system which was built in the multifunctional synthesizer. After HPLC purification, the purified¹⁸F-FDOPA solution was collected and passed through a sterilizing filter into a collection bottle. The final¹⁸F-FDOPA injection was obtained for quality control (QC) determination. The QC indexes of the final products were detected： the injection was colorless and transparent, pH value was at 4 to 5.5, radiochemical purity >98%, radionuclide purity >99%, specific activity >1.9 GBq/μmol, K_2.2.2 content <50 mg/L, methanol content <0.01%, alcohol content <0.01%, dichloromethane content <0.01 mg/L, dimethylformamide content <15 mg/L, bacterial endotoxin test <0.100 EU/mL, sterility test 0 cfu/mL,and abnormal toxicity test was negative. PET/CT imaging of rats was performed by intravenous injection of¹⁸F-FDOPA half an hour after the intraperitoneal injection of carbidopa, PET/CT scan was performed after 100 min post-injection. The imaging of¹⁸F-FDOPA showed symmetry high uptake in the bilateral striatum of normal rats. The decay-corrected radiochemical yield of¹⁸F-FDOPA from the¹⁸F-fluoride was (63.1±3.8)% (n=10) at the end of synthesis (EOS), the radiochemical purity was no less than 98%, and the total radiosynthesis time was within 80 min. The quality control results demonstrated that the quality indexes of the final injection solution met the relevant requirements of radiopharmaceutlcals, which were well-suited for clinical application. An efficient and high reproducible automatic method for the radiosynthesis of¹⁸F-FDOPA with high radiochemical yields and good radiochemical purity is obtained and performed via a multi-step reaction on the multifunctional synthesizer.¹⁸F-FDOPA can be used for animal and human PET imaging.     

18F-NaF注射液的制备及新西兰兔骨折显像

由外伤或肿瘤骨转移造成的隐匿性骨折和愈合情况的准确诊断对制定合适的治疗方案具有非常重要的意义。为考查¹⁸F-NaF PET显像用于骨折诊断的诊断效能,本研究制备了¹⁸F-NaF注射液,并对其进行了质量控制和稳定性研究,然后建立新西兰兔骨折动物模型,模型建立约2周后进行了¹⁸F-NaF PET显像和⁹⁹Tc^m-亚甲基二磷酸盐（⁹⁹Tc^m-MDP）SPECT显像的自身对照实验,并对显像效果进行了比较。结果表明：¹⁸F-NaF的产量大于37 GBq,各项检验结果均符合质控要求,40 ℃下放置8 h和30 ℃下放置10 h所有检验结果均无明显变化;¹⁸F-NaF PET和⁹⁹Tc^m-MDP SPECT两种显像方式均可见全身骨骼,骨折部位呈明显放射性浓聚,但¹⁸F-NaF给药后30 min即可进行PET显像,骨折部位显示更为清晰,骨折部位与对侧正常骨骼的放射性摄取比（T/NT）明显高于⁹⁹Tc^m-MDP,而⁹⁹Tc^m-MDP需在给药后2 h才能进行SPECT显像。本研究表明¹⁸F-NaF PET对骨折的显像性能优于⁹⁹Tc^m-MDP,可明显提高检查流通量和诊断效能。     

一种靶向TGR5的胆汁酸类化合物的~(18)F标记与初步评价

G-蛋白偶联受体(TGR5)是一类位于细胞膜上的胆汁酸受体,与体内的糖代谢、能量代谢和胰高血糖素样多肽-1的分泌密切相关。相对于正常组织,TGR5在多种肿瘤组织中过量表达,并与患者的预后相关,是肿瘤诊断、治疗和预后评估的一个潜在靶点。因此,利用点击化学的方法简单高效的制备了一种靶向TGR5的18F-PET探针[18F]FEA-LCA。该探针具有较高的放射化学产率(66%~74%)、比活度(大于300PBq/mol)和放射化学纯度(大于99%)。[18F]FEA-LCA具有其母体化合物LCA相似的亲脂性,并具有良好的体外稳定性。本工作为进一步研究[18F]FEA-LCA作为TGR5过量表达的肿瘤的PET探针奠定了良好的基础。     

~(18)F标记正电子分子探针在肿瘤受体显像的应用

肿瘤受体显像具有高亲和性、高特异性、高选择性及良好的药代动力学特性,在肿瘤的诊断和分期中具有重要作用。本文根据不同的肿瘤受体,对生长抑素(SST)受体、血管活性肠肽(VIP)受体、肿瘤生长因子受体、类固醇激素(SH)受体类肿瘤受体显像剂的18F标记的正电子分子探针进行了综述。     

PET显像剂~(18)F-氟化钠的制备、作用机制和临床应用

~(18)F-氟化钠是一种正电子发射计算机断层显像(PET)药物,主要用于成骨性反应活跃的骨疾病、尤其是恶性肿瘤骨转移的诊断。~(18)F-氟化钠PET骨显像具有高灵敏度和高特异性的特点,能更早发现99 Tcm-亚甲基二膦酸盐(99 Tcm-MDP)单光子发射计算机断层显像(SPECT)不能探测到的病灶。这对肿瘤治疗方案的选择和预后判断具有重要的临床意义。另外,18 F-氟化钠也能够有效鉴别破裂高风险的冠状动脉粥样硬化斑块。本工作就PET显像剂~(18)F-氟化钠的制备、质量控制、药理作用、辐射安全和临床应用作出综述。     

肿瘤PET分子探针3-O-(2-18F-氟乙基)-L-多巴的合成及初步生物学评价

正电子类氨基酸显像剂是¹⁸F-氟代脱氧葡萄糖（¹⁸F-Fluorodeoxyglucose,¹⁸F-FDG）在临床肿瘤PET显像应用中的重要补充。针对6-¹⁸F-氟-L-多巴（¹⁸F-FDOPA）前体制备及标记过程的复杂性,本研究设计合成了一种新型¹⁸F-标记的氨基酸类肿瘤PET显像剂3-O-(2-¹⁸F-氟乙基)-L-多巴（3-O-(2-¹⁸F-fluoroethyl-L-DOPA,¹⁸F-FEDOPA）,并对其内生物分布及肿瘤PET显像进行了评价。以L-多巴（L-DOPA）为原料经多步反应合成标记前体化合物-N-叔丁氧羰基-(3-O-甲苯磺酸酯乙基-4-O-叔丁氧羰基)-L-多巴甲酯,通过¹⁸F-亲核取代反应实现放射性标记,经半制备高效液相色谱纯化、盐酸水解、NaOH中和后得到¹⁸F-FEDOPA注射液。放化合成时间为90 min,放化产率（33±6）%（n=10,衰减校正）,放射性比活度为55 GBq/μmol,放化纯度>99％,4 h后测定放化纯度>95%,稳定性良好。小鼠体内生物分布表明,¹⁸F-FEDOPA主要经肾脏代谢,心脏和脑组织摄取值较低,骨骼摄取随时间无明显变化。microPET/CT显像显示,¹⁸F-FEDOPA在H22和S180肿瘤组织有明显摄取;与¹⁸F-FDG相比,¹⁸F-FEDOPA在注射60 min时肿瘤与心（或脑）的比值高。因此,¹⁸F-FEDOPA有望成为一种新型氨基酸代谢类肿瘤PET显像剂。     

177Lu标记单克隆抗体Rituximab

以CHX-A''''-DTPA和p-SCN-Bz-DTPA为双功能螯合剂,分别对Rituximab进行偶联,用¹⁷⁷Lu进行标记,制备¹⁷⁷Lu-Rituximab。在优化条件下,¹⁷⁷Lu对单抗偶联物CHX-A''''-DTPA-Rituximab和p-SCN-Bz-DTPA-Rituximab的标记率和放化纯度均大于99%。室温及37 ℃条件下,¹⁷⁷Lu-Rituximab在各种测试体系中均显示良好的体外稳定性。在正常小鼠体内的生物分布结果显示,¹⁷⁷Lu-Rituximab发生了分解,游离的¹⁷⁷Lu在骨中形成较高浓集。¹⁷⁷Lu-p-SCN-Bz-DTPA-Rituximab比¹⁷⁷Lu-CHX-A''''-DTPA-Rituximab的体内清除快,而且游离¹⁷⁷Lu的骨摄取低,结果表明,p-SCN-Bz-DTPA更适于作为双功能螯合剂用于单抗的¹⁷⁷Lu 标记。     

新型心肌灌注显像剂~(99)Tc~m-CO-MIBI与~(99)Tc~m-MIBI的药理学比较

以犬为实验动物,99Tcm-CO-MIBI和99Tcm-MIBI为显像剂,采用自身对照的方法,通过采集血样、采集动态图像和全身显像获得药物在犬体内的代谢动力学参数、生物分布、靶与非靶放射性摄取比和全身、心脏平面及断层影像等药效学结果。结果显示,99Tcm-CO-MIBI符合一次静脉给药的血药动力学二室开放模型,快相及慢相半衰期分别为Tα(1/2)=1.46±0.13 min,Tβ(1/2)=97.30±20.50 min,全血总清除率CL=436.36±54.77 mL/h。心、肺、肝时间-放射性曲线显示,在注射约40 min后,99Tcm-CO-MIBI肝脏曲线明显低于心肌曲线。多时间点心脏与肺脏及肝脏的放射性摄取比亦表明99Tcm-CO-MIBI在心肌摄取高,滞留久,肺本底低,肝脏药物排出比99Tcm-MIBI明显快。注射99Tcm-CO-MIBI后10~120 min内均可获得清晰的心肌图像,40 min后下壁心肌显示不再受肝内放射性干扰。表明99Tcm-CO-MIBI犬体内生物分布优异,有望成为一种新型心肌灌注显像剂。     

Preparation and Clinical Application of 18F-DCFPyL

¹⁸F-DCFPyL, a PSMA-based PET imaging agent for prostate cancer, was auto synthesized and evaluated. Following the direct nucleophilic heteroaromatic substitution with ［¹⁸F］fluoride at the ortho-position of precursor, the deprotection of the ester moieties of the intermediate with different acids was attempted to obtain a good hydrolysis yield. The biodistribution in normal NIH mice and PET/CT imaging for a patient with biochemical recurrence of prostate cancer were also performed. The results showed that no remarkable discrepancy of the hydrolysis efficiency was found among three kinds of acids, H₃PO₄, HCl and HI, which were 17.1%, 16.9% and 18.4%, respectively with a specific activity of 54 to 90 GBq/μmol. The highest levels of radioactivity in the NIH mice were observed in the kidneys. Meanwhile, the uptake of the tracer in the blood was declined rapidly and a low accumulation of the radio-tracer was observed in most of the other organs. ¹⁸F-DCFPyL PET imaging for a postoperative patient with biochemical recurrence of prostate cancer can detect small metastatic foci that can not be detected by the CT. ¹⁸F-DCFPyL was synthesized reliably and repeatedly by domestic synthesis module and it passed the quality control. It has satisfactory properties in vivo and is probably suitable for early diagnosis of prostate cancer and detection of lesions in patients with biochemical recurrence of prostate cancer.     

两种~(18)F标记苯乙烯基吡啶衍生物前体化合物的合成研究

18F-AV45是首个FDA批准上市的阿兹海默症(AD)显像用PET药物,其异构体18F-YG也可能具有更好的性能。为促进18F-AV45的国产化及评价其异构体18F-YG在AD显像方面的性能,本工作合成了两者的标记前体化合物。具体方法为:以4-氨基苯乙烯为原料,经过碳酸叔丁基保护和碘甲烷甲基化,得到BOC保护的对甲胺基苯乙烯;该苯乙烯结构双键上的氢原子被TEG链修饰过的碘吡啶取代后,以对甲苯磺酸基保护TEG侧链羟基,得到目标产物AV105和YGQT,总产率分别为57%和66%。ESI-MS、1 H NMR验证结果显示,两种前体化合物结构正确。前体化合物AV105和YGQT的合成为进一步研究18F-AV45及其异构体18F-YG在AD显像方面的性能提供了基础。     

原发性高血压病患者99Tcm-MIBI心肌显像及其左室心肌质量测定

对33例临床确诊的原发性高血压病患者和18例正常对照者进行常规^99Tc^m—MIBI心肌显像后重建HSA、HVA和LVA，并对图像进行分析和打印，利用体视学原理测定左室心肌质量，以探讨原发性高血压病患者左室心肌质量的改变情况。结果表明，心肌显像结合体视学方法测定左室心肌质量可行且有效，用该方法可测定原发性高血压病患者左室心肌质量，还可同时观察心肌的血供和结构改变情况。