Labeling and stability study on ^99mTc—tissue plasminogen activator as thrombus and tumor imaging agent

Tissue plasminogen activator(tPA),due to its stability in acidic solution,could be conveniently labeled with ^99mTc by using stannous chloride method.More than 90% of biochemical activity was remained after the process of labeling and separation,The stability of ^99mTc-tPA was studied at different time and different pH values,respectively.The study indicated that ^99m Tc-tPA would be a potential imaging agent for thrombus and tumor.     

^99Tc^m—CQDO和^99Tc^m—CQDO—MeB牟小鼠体内分布和药代动力学比较

以氯化亚锡为还原剂制备了＾９９Ｔｃ＾ｍ－ＣＱＤＯ及其甲基硼酸加成物＾９９Ｔｃ＾ｍ－ＣＱＤＯ－ＭｅＢ经萃取纯化,其放化纯度均〉９０％。小鼠体内分布表明,两者均能被小鼠心肌迅速摄取;＾９９Ｔｃ＾ｍ－ＣＱＤＯ的心肌清除快,１０ｍｉｎ时已清除至（５．８８±１．６６）％ＩＤ／ｇ;而＾９９Ｔｃ＾ｍ－ＣＱＤＯ－ＭｅＢ在心肌内却有较长的滞留时间,６０ｍｉｎ时心肌摄取仍有（７．４２±０．１７）％ＩＤ／ｇ。两者在血中     

^99mTc—ECD brain SPECT imaging in patients with acquired immunodeficiency syndromes

In order to investigate the changes of regional cerebral blood flow (rCBF) in patients with acquired immunodeficiency syndromes (AIDS), 99mTc-ECD brain SPECT imaging was performed in 5 patients with AIDS and 16 sex and age matched normal controls, and the rCBF percentages compared to the cerebellum were calculated using a semi-quantitative processing software. Hypoperfusions in the right and left frontal, temporal, porietal lobe, basal ganglia and left thalamus were seen in 1 patient with dementia. Hypoperfusions in the right and left frontal and temporal lobe were seen in 4 asymptomatic patients. The rCBF in the right and left frontal, temporal, porietal lobe, basal ganglia and thalamus, front and pons were decreased significantly in patients with AIDS than those of the control subjects (p <0.005). It is concluded that there exists reduced cortico-subcortical rCBF in AIDS patients.     

^99mTc—人血白蛋白聚合大颗粒肺显像剂的研制

本工作采用吐温-80作分散剂和稳定剂,提高了人血白蛋白聚合大颗粒的粒度均匀性和产物浓度。冻干品的稳定性达8个月,标记率在95％以上,采用离心分离法和微型纸层析法相结合,可得到~(99m)Tc-MAA及还原~(99m)Tc(Ⅳ)和游离~(99m)Tc(Ⅶ)的百分率。未冻干MAA样品的稳定性达51天.小鼠的器官分布试验达到美国药典同类产品的标准。其毒性试验结果达到中国药典的要求。兔子的γ照相结果表明肺的摄取率高达90％。注射~(99m)Tc-MAA的免子2小时后,仍然保持高的肺摄取率,说明此药盒可用作肺显像诊断和研究。     

经Avidin—Biotin系统^99mTc标记单抗及其在荷瘤裸鼠体内分布研究

采用Ａｖｉｄｉｎ－Ｂｉｔｉｎ系统进行了抗人黑色素瘤单抗Ｎｇ７３的＾９９ｍＴｃ标记、研究了标记条件，方法和标记抗体在荷裸鼠活体内的生物学分布１。结果表明，ｐＨ＝８和ＳｎＣｌ２适量时标记效果最好；两步法Ｂ的Ｔ／ＮＴ和ＩＤ％／ｇ值均明显优于两步法Ａ。经Ａｖｉｄｉｎ－Ｂｉｏｔｉｎ系统＾９９ｍＴｃ标记单抗可用于放射免疫显像。     

^99mTc—Ec与^99mTc—DTPA肾动态显像判断肾功能的研究

用９９ｍＴｃ－Ｅｃ与９９ｍＴｃ－ＤＴＰＡ两种肾功能显像剂分别对５４例受检者进行肾动脉血流灌注及肾功能动态显像，通过感兴趣区技术获得ＥＲＰＦ或ＧＦＲ值及肾功能曲线。１０例正常人的ＥＲＰＦ值为４６５．１８±１２８．８７ｍｌ／ｍｉｎ，ＧＦＲ值为１１０．４１±１６．４１ｍｌ／ｍｉｎ；糖尿病及糖尿病性肾病患者随病程进展及临床分型不同，其ＥＲＰＦ、ＧＦＲ或正常、或升高、或降低。据ＥＲＰＦ、ＧＦＲ的定量分析，可判定肾病的病程、转归和疗效；慢性肾炎、肾盂肾炎、ＩｇＡ肾病、肾病综合征等慢性进行性肾实质病变患者，其ＧＦＲ、ＥＲＰＦ降低的幅度可反映肾小管或肾小球功能受损的程度     

Preparation and biological evaluation of ^99Tc^m-labelled fatty acids

The aim of the present work was to develop radiolabelling fatty acids based on ^99Tc^m carbonyl chemistry for heart imaging. Undecanoic acids functionalised with iminodiacetatic acid and cysteine were radiolabelled with [^99Tc^m（CO）3（H2O）3]^＋ intermediates, and their radiolabelling conditions were carefully studied. Biodistribution of ^99Tc^m（CO）3-CYST FAC 11 and ^99Tc^m（CO）3-IDA FAC 11 were observed in normal mice. The results showed that two ^99Tc^m-labelled compounds had similar profile in terms of high initial radioactivity uptake and rapid washout of radiotracers in the heart. ^99Tc^m （CO）3-IDA FACII was mainly excreted via hepatobiliary system in contrast to ^99Tc^m （CO）3-CYST FAC11, which was excreted from urinary system. It may be in part attributed to the more lipophilicity of ^99Tc^m （CO）3-IDA FAC11 than ^99Tc^m （CO）3-CYST FAC11.     

^99Tc^mN—CHPDTC的制备及生物分布

以SnCl2 ·2H2 O为还原剂 ,N 甲基二硫代肼甲酸甲酯 (DTCZ)为N3- 离子提供体制备[99TcmN]int2 + 中间体 ,然后与配体二水·N 环庚基 二硫代氨基甲酸钠 (CHPDTC)发生配体交换反应 ,得到放化纯大于 90 %的99TcmN CHPDTC配合物。99TcmN CHPDTC在制备后放置 7h放化纯不变 ,分配比lgD =1 5 0。小鼠体内生物分布结果表明 ,99TcmN CHPDTC有较高心肌摄取和较好的心肌滞留。在注射后 5 ,30 ,60min时 ,心肌摄取量 (ID/ (%·g- 1) )分别为 17 17,16 82 ,19 18。在注射后 60min时 ,R(心 /血 ) ,R(心 /肺 ) ,R(心 /肝 )比值分别为 7 10 ,1 4 3,0 4 1。有望成为新型心肌灌注类显像剂     

Biodistributionand pharmacokinetics of 99mTc-CQDO and 99mTc-CQDO-MeBfor newmyocardial imaging agent

A comparison of ^99mTc-CQDOand ^99mTc-CQDO-MeB has been made for biodistribution and pharmacokinetics. ^99mTc-CQDOand its adducts of methaneboronic     

Preparation and biodistribution of ^99Tc^m-PIDP as bone imaging agent

A novel zoledronic acid derivative,1-hydroxy-2-(2-propyl-1H-imidazol-1-yl)ethane-1,1-diyldiphosphonic acid (PIDP),was synthesized by three-step reactions from 2-propyl-1H-imidazole.It was labeled with 99Tcm in conditions of 0.1 mg SnCI2.2H2Cl2·2H2O at pH 6.0 and 99TcmO4-in aqueous solution for 20 min at room temperature.The labeling yield and radiochemical purity of 99Tcm-PIDP are both higher than 95%.The biodistribution results show that the bone uptake is up to 8.47%ID/g which is the maximum of bone uptake at 30 min after injection of 99Tcm-PIDP in mice.The pharmacokinetic parameters can be estimated from the exponential equation of C=59.565e-11.307t+ 2.069e-1.211t.The clear bone image of rabbit was obtained at 120 min after injection of 99Tcm-PIDP.The results indicate that 99Tcm-PIDP has highly selective uptake in the skeletal and low uptake,rapid clearance in soft tissues,so it would be a potential novel bone imaging agent.     

新型骨显像剂99Tcm-ZL的制备和动物实验研究

以氯化亚锡为还原剂、用99Tcm标记唑来膦酸(ZL)制得99Tcm-ZL,研究了SnCl2·2H2O和ZL的用量以及溶液pH对标记率的影响,在pH=3-9、ZL的用量大于2mg和SnCl2·2H2O的用量大于40μg时,室温反应8min,可获放化纯和标记率大于90%的99Tcm-ZL,标记后6h内放化纯度保持不变.并对99Tcm-ZL的小鼠体内分布和兔显像进行了研究.小鼠体内生物分布表明,静脉注射后30min时,骨摄取达13.45%ID/g,am骨/肌和am骨/血分别达到28.01和16.96;兔显像表明,静脉注射75min后,即可获得清晰的骨显像.研究表明,99Tcm-ZL是一种稳定性好、制备简便、值得进一步深入研究的骨显像剂.     

99Tcm-HEDTMP的制备及其生物分布

采用SnCl2还原法制备了^99Tc^m－HEDTMP，研究了标记物的体外稳定性、兔SPECT骨扫描及小鼠体内分布。结果表明，^99Tc^m－HEDTMP具有较高的体外稳定性，5h内放化纯度＞95％；兔骨骼系统显像清晰；小鼠体内分布结果表明标记物主要被小鼠骨骼摄取，其它非目标组织的摄取较低、骨清除较快。这表明^99Tc^m－HEDTMP是非常有希望的新型骨显像剂。     

99Tcm-DTPA-Gd的制备及其生物学分布

应用99Tcm标记顺磁对比剂Gd-DTPA并研究其生物学分布特性。99Tcm在氯化亚锡还原下一步法标记Gd-DTPA,采用薄层纸层析法(TLC)分析标记率大于98%,室温放置6 h内放化纯稳定。三氯乙酸沉淀法测得99Tcm-DTPA-Gd在家兔血浆中的蛋白结合率为(3.80±0.25)%。正常昆明小鼠体内分布实验显示,注射99Tcm-DTPA-Gd后1 min血液的放射性摄取为(14.79±9.77)%ID/g,肾脏的摄取为(26.02±8.50)%ID/g;心、肝、脾和肺有少量分布,脑组织分布最少(1%ID/g);注射99Tcm-DTPA-Gd 30～60 min后多数脏器的滞留小于1%ID/g。正常成年家兔注射99Tcm-DTPA-Gd后采用肾动态显像模式观察60 min内的分布和排泄,显示99Tcm-DTPA-Gd主要经肾脏排泄,摄取高峰时间约为5～10 min,半排时间约为10～20 min,其它脏器无特异性滞留。     

受体显像剂99mTc-NCAM在小鼠脑组织中的药物代谢动力学研究

对N-甲基-D-天冬氨酸(NMDA)受体拮抗剂锝标记N-[2-(N-(2-巯基乙基))氨基乙酰基]-N-(2-巯基乙基)-3,5-二甲基金刚烷胺基乙酰胺(99mTc-NCAM)进行小鼠脑组织中药物动力学研究。KM小鼠尾静脉注射0.2mL(7.4MBq)99mTc-NCAM,分别于注射后5、10、30、60、120、180min处死,取大脑皮层、纹状体、海马、小脑和丘脑,称重和测计数。以相同的时间点,小鼠断尾取血20μL,测计数。用药物动力学定域模型进行脑组织和血药动力学研究。结果表明,99mTc-NCAM静脉注射给药后迅速进脑,在大脑皮层和海马有较高的摄取,最高摄取分别为1.51±0.13%ID/g和0.74±0.002%ID/g。理论计算表明,99mTc-NCAM在小鼠体内符合二室模型,并获得各种脑组织和血液的药物动力学方程和参数。99mTc-NCAM能透过血脑屏障进入小鼠脑内特定区域,以NMDA受体分布最多的大脑皮层和海马摄取较多,可望成为一种新的NMDA受体显像剂,用于一些神经退行性疾病的诊断预后等。     

新型乏氧肿瘤显像剂^99Tc^m-MNLS、^99Tcm-MLS的合成及其在小鼠体内的生物分布

合成了含有硝基咪唑基团的磷酸酯衍生物2-（2-methyl-5-nitro-1H—imidazol-1-yl）Ethyl Dihydrogen Phosphate（MNLS）和它的非硝基类似物2-（2-methyl-1H-imidazol-l-yl）Ethyl Dihydrogen Phosphate（MLS）,采用^99Tc^m直接法对其进行标记,并研究了^99Tc^m-MNLS和^99Tc^m-MLS的理化性质及其在荷EMT-6小鼠体内的生物分布。采用最佳标记条件后,^99Tc^m-MNLS和^99Tc^m-MLS的标记率均〉90％。荷EMT-6小鼠体内生物分布表明：^99Tc^m-MNLs的肿瘤放射性摄取率、肿瘤与肌肉和肿瘤与肝的放射性摄取比（T／NT）（120min时分别为2．99±0．25％ID／g、5．90和1．03）显著高于已知的乏氧显像剂^99Tc^m-HL91（120min时分别为0．93±0．13％ID／g、3．59和0．17）和不含硝基基团的类似物^99Tc^m-MLS（120min时分别为1．61±0．13％ID／g、5．40和0．13）。与^99Tc^m-MLS相比^99Tc^m-MNLS配体中的硝基对于肿瘤的摄取影响很大,这表明^99Tc^m-MNLS的肿瘤摄取与其乏氧机制有关。上述研究结果表明,^99Tc^m-MNLS具有肝摄取低,肿瘤摄取较高的优点,作为潜在的新型乏氧肿瘤显像剂,值得进一步研究。     

99TcmN-DMCHI和99Tcm-DMCHI的制备及其生物分布

合成并表征了新的异腈配体2,3-二甲基环己基异腈(DMCHI)及其铜络盐。分别通过配体交换法和直接标记法制备得到放化纯大于95％的脂溶性配合物^99Tc^mN-DMCHI和^99Tc^m-DMCHI,二者在室温下均可稳定6h以上。在正常小鼠体内的生物分布实验结果表明,^99Tc^mN-DMCHI和^99Tc^m-DMCHI在血液中均有较高的摄取和很好的滞留,而且血／心、血／肝和血／肺比值均大于1,有望用于心血池显像。     

心肌显像剂99mTcN-BMPBDA的制备及动物体内分布研究

为了寻找新的具有亲心肌性质的＾９９ｍＴｃＮ药物,合成了一种新的Ｎ２Ｓ２配体：Ｎ,Ｎ＇－二（２－巯基丙基）－１,２－苯二胺（ＢＭＰＢＤＡ）。以ＳｎＣｌ２为还原剂,Ｈ２ＮＮＨ－（Ｃ＝Ｓ）－ＳＣＨ３为Ｎ＾３－给予体,通过交换反应制备了放化纯大于９０％的＾９９ｍＴｃＮ－ＢＭＰＢＤＡ。探讨了ｐＨ值对＾９９ｍＴｃＮ－ＢＭＰＢＤＡ放化纯的影响,并对其小鼠生物分布进行了研究。结果表明,＾９９ｍＴｃＮ－ＢＭＰＢＤＡ     

99Tcm-MAG3-Lys-mPEG的制备及其在小鼠体内的分布

以mPEG-5000、Fmoe-Lysine和MAG3为原料，经过五步反应合成了载体MAG3-Lys-mPEG；对其进行^99Tc^m标记后，进一步研究了标记物的体外稳定性及其在小鼠体内的生物分布。结果表明，^99Tc^m-MAG3-Lys-mPEG的标记率〉98％；标记物在体外有很好的稳定性，在生理盐水中放置24h时，放化纯度〉91％；在血清中温浴16．5h时放化纯度仍〉92％；标记物在小鼠体内的血液清除较快，在肾脏中的摄取最高，标记物主要经肾脏通过尿液排出体外。mPEG有可能用作反义核酸的有效载体。