胆碱模块自动化合成11C-carfentanil及Micro PET显像

为快速、高效合成中枢神经阿片受体显像剂¹¹C-carfentanil(¹¹C-CFN),对国产商业化¹¹C-胆碱合成模块略做改动,并优化了合成条件。结果表明,采用4-哌啶乙酸钠,4-[(1-丙羰基)苯胺]-1-(2-苯乙基)[钠盐]作前体,DMSO作溶剂,¹¹CH_3-triflate作甲基化试剂,在胆碱模块上采用反应瓶法,可自动化合成¹¹C-CFN。合成的¹¹C-CFN活度＞14.8 GBq、比活度＞1.4×10¹⁴Bq/g、放化纯度＞99%,校正合成效率＞80%（n=55,以¹¹CH₃-triflate计算）,全部合成时间为18 min。经Micro PET/CT证实,¹¹C-CFN可用于μ阿片受体的PET显像研究。     

11C-(-)间羟基麻黄素的合成及Micro PET显像

¹¹C标记(-)间羟基麻黄素（¹¹C-(-)HED,¹¹C-HED）是一种交感神经系统显像剂,可用于心肌和肾上腺肿瘤的显像。碘代甲烷与(-)间羟胺直接甲基化反应,生成¹¹C-HED,经HPLC梯度淋洗纯化;通过动物实验研究在¹¹C-HED中添加前体后对心肌摄取的影响。结果表明,用碘代甲烷作甲基化试剂可减少副反应,分别用含3%乙醇和10％乙醇的0.24 mol/L磷酸二氢钠溶液梯度淋洗,能有效去除前体间羟胺,同时放化纯度从93.2%提高到98%。¹¹C-HED在动物体内的生物分布表明,注射含2 mg/kg前体间羟胺的¹¹C-HED后,30 min时心肌摄取明显降低,而肾上腺摄取增高。Micro PET显像证实,注射¹¹C-HED后正常心肌显像,但加入前体后心肌摄取降低,清除加快。以上结果提示,分别用含3%和10%乙醇的0.24 mol/L磷酸二氢钠溶液梯度淋洗可提高产品化学纯度和放化纯度;在¹¹C-HED中加入前体间羟胺后对心肌摄取明显降低,而肾上腺摄取增高。     

多巴胺转运蛋白显像剂11C-β-CFT的全自动化合成

通过对反应条件的优化及合成模块的改进,探索了一种高效、全自动化合成¹¹C-β-CFT的方法。以¹¹CO₂为起始原料与LiAlH₄、HI或HBr反应生成¹¹CH₃I（或¹¹CH₃Br）,再转化成Triflate-¹¹CH₃,最后与nor-β-CFT进行甲基化反应合成¹¹C-β-CFT。整个合成工艺实现了全自动化,产品校正放化产率为70.2%±1.8%,放化纯度大于95%。用新方法合成的¹¹C-β-CFT无菌注射液经pH测定、HPLC检测、内毒素检查、细菌培养及异常毒性检查,均符合注射液要求。用制备的¹¹C-β-CFT对正常志愿者与帕金森病患者进行PET显像,PET显像显示正常对照者双侧纹状体影像清晰,帕金森病患者双侧纹状体不对称性摄取减低。该工艺实现了¹¹C-β-CFT全自动化,放化产率高,工艺简单,有利于工作人员放射防护,显像效果良好,可满足临床需要。     

11C-Gefinitib自动化合成及Micro PET显像

Gefinitib是小分子EGFR(epidemal growth factor receptor)抑制剂,用于非小细胞肺癌治疗。本研究以11C-CH3-Triflate为甲基化试剂,全自动合成了11C-Gefinitib,并用荷A549肿瘤为模型评价了肿瘤特异性摄取。在国产PET自动化11C多功能合成模块上,用11C-CH3-Triflate与7-去甲基Gefinitib在碱性条件下反应,经HPLC纯化和固相萃取得11C-Gefinitib,采用MicroPET/CT显像评价肿瘤特异性摄取。结果表明,自动化合成11C-Gefinitib占时28 min,合成效率为30%–35%(校正效率,n>5),产品放化纯度大于99%,比活度为55.5GBq/μmol。Micro PET/CT显像表明,荷A549肿瘤明显摄取放射性,并被50 mg/kg冷Gefinitib所阻断。结果表明,11C-Gefinitib有望用于临床Gefinitib治疗非小细胞肺癌疗效评价。     

O-(2-[18F]氟乙基)-5-羟基-L-色氨酸(5-18FEHTP)的合成动物体内分布及MicroPET显像

通过对现有CTI公司计算机控制的化学合成模块(CPCU) 进行改造,首次合成了L-5-羟基色氨酸类似物(5-18FEHTP),并用高效液相(HPLC) 检测其放化纯度,所得的产品用于昆明小鼠的S180肉瘤模型显像。结果显示,采用改进方法合成5-18FEHTP的总时间是45min,纯化时间是20min,放化收率为12-16%(n=15),产品的放化纯度大于98%。MicroPET显像结果表明,5-18FEHTP在S180肉瘤浓集程度明显高于周围其它组织。以上结果提示利用CPCU半自动合成5-18FEHTP,方法简便、稳定、产品纯度较高。动物生物分布和显像结果表明5-18FEHTP可能成为一种新的PET显像剂。     

~(11)C标记雷氯必利合成效率的影响因素

本文以11 C-Triflate-CH3为甲基化试剂,使用国产模块PET-CM-3H-IT-I合成11 C标记化合物雷氯必利(11 C-Raclopride),研究其合成过程中的碱量、溶剂、反应温度、前体量及产品淋洗条件对合成效率的影响,优化11 C-Raclopride的合成条件。优化后的合成条件为:以0.2mL丙酮为溶剂,前体浓度1.5~3.0g/L,反应温度为室温(25℃),碱量0.30~1.25eq,11 C-Raclopride的合成效率(64.82±4.74)%(n=46,以11 C-Triflate-CH3计校正效率),产品的放化纯度大于97%,比活度为(423.61±13.43)GBq/g,从收集11 C-CO2至得到11 C-Raclopride终产品的总合成时间为23 min,产量(6.9±0.87)GBq(n=46)。通过优化合成工艺,实现了稳定性和重复性良好的全自动化合成11C-Raclopride,且产品满足临床使用需要。     

淀粉样蛋白显像剂~(11)C-PIB的自动化制备优化及临床初步应用

采用国产自动化碘代甲烷仪,通过氢化锂铝/四氢呋喃(LAH/THF)还原法制得的~(11)C-碘代甲烷(~(11)CH3I),在线转换成活性更高的~(11)C-三氟磺酸甲酯(~(11)CH3OTf),通入锥形反应瓶内,和1.0mg PIB前体6-OH-BTA-0丁酮溶液在盐冰浴条件下反应,利用改进的HPLC方法纯化产品,并对最终产品进行质量控制。用昆明小鼠进行急性毒性试验,并行4例临床AD患者及1例正常人PET/CT显像。结果表明,改进后的自动化制备工艺,最终得到可供注射的~(11)C-PIB 10%乙醇溶液,改进后使用前体原料更少,产率稳定。改进后的~(11)C-PIB制备路线稳定可靠,初步临床研究表明,制备的~(11)C-PIB显像剂可以用于阿尔茨海默病诊断。     

5-羟色胺转运体显像剂[125I]-ADAM的合成以及初步生物学分布

完成了5-羟色胺转运体显像剂[^125I]-2-（（2-（（二甲基氨基）甲基）苯基）巯基）5-碘苯胺（[^125I]-2-（（2-（（dimethylamino）methyl）phenyl）thio）-5-iodophenylamine，[^125I]ADAM）的制备和初步生物学特性的评价。以2，5-二溴-硝基苯和2-巯基苯甲酸为起始原料，合成标记前体5-三丁基锡-2-[2-（二甲基氨基甲基苯基巯基）]苯胺，采用双氧水标记法标记；并进行了大鼠体内和脑内的初步生物分布研究。合成标记前体5-三丁基锡-2-[2-（二甲基氨基甲基苯基巯基）]苯胺的总产率为42％，用[^125I]NaI标记后，TLC测放射化学纯度（RCP）大于95％；^125I-ADAM大鼠脑摄取高，在富含5-羟色胺转运蛋白的丘脑中的摄取随时间延长而增加，滞留时间长，其特异结合在注射后60min、120min和240min分别为3.38，3．62和4．36。本合成方法总收率高，标记方法简便，放射化学纯度高，^125I-ADAM初始进脑量高，与SERT结合特异，可望用于研究脑内SERT功能。     

AD显像剂11C-PIB合成效率的影响因素

¹¹C-PIB是诊断阿尔茨海默病（AD）的特征靶Aβ斑块的正电子放射性药物,本工作系统研究了以¹¹CH₃-Triflate为甲基化试剂合成¹¹C-PIB合成的影响因素。在国产碳多功能合成仪上, 研究前体量、溶剂、反应温度及体系的pH等对¹¹C-PIB效率的影响,并对合成条件进行优化。结果显示：前体量、溶剂、反应温度及体系的pH均明显影响合成效率。优化后的合成条件为：丙酮为溶剂,前体浓度为5 g/L,反应温度为常温,pH为中性。在此条件下,¹¹C-PIB的合成效率为65.2%±4.7%(n=8,校正效率),产品的放化纯度大于99%,比活度为70.6 GBq/g（18.0 TBq/mmoL）。从¹¹CO₂到¹¹C-PIB的合成时间为30 min, 单次合成的产量为3.7 GBq。以上结果表明,通过优化合成条件,可以稳定、高质量地合成¹¹C-PIB,以满足临床需要。     

PET肿瘤显像剂~(18)F-氟乙基胆碱的自动化合成

18F-氟乙基胆碱(18F-FECH)是反映胆碱代谢的PET肿瘤显像剂,在肿瘤特别是脑肿瘤诊断中显示出良好的应用前景。为了方便临床应用,本工作利用PET-MF-2V-IT-I型18F多功能合成模块,自动化合成18F-FECH。首先18F-与1,2-乙二醇二对甲苯磺酸酯在90℃下发生亲核取代反应,产物未经纯化即与N,N-二甲基乙醇胺在100℃下发生烷基化反应,此后经过C18柱和CM柱进行分离纯化,得到目标产物。整个过程需时约40 min,最终产品放化收率30%(未经时间校正),放化纯度≥99%,室温下可稳定放置6 h。本方法简便易行,合成时间短,收率较高,产品稳定性好,且其它各项指标均符合规定,为临床常规应用提供了保证。     

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.     

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%。     

^11C-Carfentanil的质量控制

^11 C标记的卡芬太尼（^11 C-Carfentanil）中载体^（12 C-Carfentanil）的含量对该药物的安全使用至关重要。利用高效液相色谱系统测量^11 C-Carfentanil注射液的化学纯度和放化纯度;液质联用方法测量比活度;应用快速内毒素检测器PTS检测产品中内毒素含量。结果表明：合成产品为无色透明澄清^11 C-Carfentanil溶液,放化纯度大于98%,比活度为1.69×1014 Bq/g,内毒素含量小于5EU/mL。以上结果表明：^11 C-Carfentanil注射液的质量符合药用要求,可满足实验和临床安全使用要求。     

11C-MET和18F-FDG PET/CT对胶质瘤诊断的价值比较

对26例胶质瘤和18例颅内良性病变患者行18F-FDG和11C-MET PET/CT颅脑显像,定性和半定量分析两种显像图像.结果显示:11C-MET和18SF-FDG PET/CT对胶质瘤诊断的准确率分别为88.6%和65.9%.半定量分析,26例胶质瘤11C-MET摄取值比值TINGmax显著高于18F-FDG的TI...     

Optimization of the Radiosynthesis of the Dopamine Transporter Imaging Agent of11C-β-CFT

The optimization for high synthesis yield was designed with ¹¹C-Triflate-CH₃I as methylation agent for dopamine transporter imaging agent of¹¹C-β-CFT. The influence factors of the synthesis process were discussed, and the optimum synthetic conditions were established. In the paper, the study showed that the amount of precursor, the irradiation time, eluated condition, the reaction solvent etc could effect the synthetic efficiency.¹¹C-β-CFT was automatic synthesized on PET-CM-3H-IT-Ⅰ with the optimum process conditions as the irradiation time 10-24 minutes, 0.5-1.0 g/L of precursor in 0.2 mL acetone: acetonitrile(1∶1, V∶V) and room temperature. We obtained a radiochemical yield of (76.93±6.49)% (n=76,¹¹C-Triflate-CH₃ EOB). The radiochemical purity of final products were over 97%. The specific activities of final products were over （56.26±1.55） TBq/g. It took 16 minutes from¹¹C-CO₂ to¹¹C-β-CFT and the radio activity of¹¹C-β-CFT were (8.07±1.94) GBq (n=76). By optimization of the technological conditions, the target product was suitable for clinical, the synthetic process was reliable and full automated, the product yield was improved and the residual problem of Sep-Pak C18 was resloved.     

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.     

PET/CT中CT的剂量与CT图像质量关系的研究

为在保证图像质量的前提下,降低PET/CT中CT扫描部分的辐射剂量提供数据依据。用GEDiscovery ST16型号PET/CT系统,按不同的采集条件扫描CT质量控制模体,测量CT图像的相关性能指标;测量在各种管电流下的加权CT剂量指数,计算不同螺距下的容积CT剂量指数;分析CT图像质量与CT剂量的关系。结果表明:CT图像高对比度分辨力不受CT剂量影响;CT图像的低对比度分辨力随CT剂量增加而提高;CT剂量能影响CT图像的均匀性;CT图像噪声随CT剂量增加而降低,且可用一表达式来表示。得出在保证一定的CT图像质量的条件下,可以适当降低PET/CT检查中CT部分的辐射剂量的结论。     

阿片受体显像剂11C-Carfentanil的前体合成及放射性标记

为合成μ-阿片受体显像剂:1-(2-苯乙基)-4-(N-苯基丙酰胺基)哌啶-4-羧酸[11C]甲酯([11C]-methyl 1-phenethyl-4-(N-phenylpropanamido) piperidine-4-carboxylate,11C-CFN),合成了标记前体:1-苯乙基-4-( N-苯基丙酰胺基)...     

Improved AutomatedSynthesis and Preliminary Animal PET/CT Imaging of 11C-acetate

To study a simple and rapidautomated synthetic technology of ¹¹C-acetate(¹¹C-AC), automatedsynthesis of ¹¹C-ACwas performed by carboxylation of MeMgBr/tetrahydrofuran (THF) on apolyethylene loop with ¹¹C-CO₂,followed by hydrolysis and purification on solid-phase extraction cartridgesusing a ¹¹C-Choline/Methioninesynthesizer made in China. A high and reproducible radiochemical yield of above40% (decay corrected) was obtained within the whole synthesis time about 8 minfrom ¹¹C-CO₂.The radiochemical purity of ¹¹C-ACwas over 95%. The novel, simple and rapid on-column hydrolysis-purificationprocedure should adaptable to the fully automated synthesis of ¹¹C-AC at several commercialsynthesis module. ¹¹C-ACinjection produced by the automated procedure is safe and effective, and can beused for PET imaging of animals and humans.