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1.
制备了99 Tcm(CO)3-BPHRGD,并进行了荷M21人黑色素瘤裸鼠体内生物学评价。在pH=7、75℃条件下反应30min,99 Tcm(CO)3-BPHRGD的标记率大于80%,纯化后标记物的放化纯度大于98%。体外稳定性实验结果显示,37℃下,标记物在生理盐水、人血清中具有很好的稳定性。荷M21人黑色素瘤裸鼠体内分布显示,注射99 Tcm(CO)3-BPHRGD后0.5、1、2、4h,标记物的瘤/血比分别为0.70±0.45、0.87±0.05、1.10±0.19、1.68±0.04。随着时间的延长,靶与非靶的放射性摄取比(T/NT)增大,表明该标记物在肿瘤细胞中的清除速度慢于其他组织。通过进一步结构修饰,改变其体内代谢途径及药代动力学性质,99 Tcm(CO)3-BPHRGD非常有希望成为一种新型肿瘤显像剂。  相似文献   

2.
制备了99 Tc m(CO)3-BPHRGD,并进行体内外生物学评价。在pH=7、75℃条件下反应30min,99 Tc m(CO)3-BPHRGD的标记率均大于80%,纯化后标记物的放射化学纯度大于98%;体外稳定性实验显示,在37℃时,标记物在生理盐水、胎牛血清及半胱氨酸溶液中具有很好的稳定性;正常小鼠体内生物分布数据显示,99 Tc m(CO)3-BPHRGD在血液中清除较快,主要通过肝肾代谢。  相似文献   

3.
为制备纳米材料SPION-DMSA及其标记物SPION-DMSA-99Tcm,探讨该标记物作为SPECT/MRI双模态显像剂的可能性,本工作先采用高温热解法合成了SPION,然后用DMSA包覆获得SPIONDMSA并进行各种表征。用99Tcm标记SPION-DMSA得到SPION-DMSA-99Tcm,并对该标记物进行荷U87MG人脑神经胶质瘤裸鼠的生物分布和显像研究。实验结果表明,SPION-DMSA具有超顺磁性,99Tcm标记率大于98%。SPION-DMSA-99Tcm在血液中清除较快,在肝脏中的摄取较高。SPIONDMSA-99Tcm与DMSA-99Tcm(Ⅴ)在小鼠体内的生物分布差异较大。SPION-DMSA-99Tcm在肿瘤中并没有明显的摄取。SPION-DMSA和SPION-DMSA-99Tcm的MRI和SPECT显像结果表明,SPIONDMSA和SPION-DMSA-99Tcm的肿瘤被动靶向作用有限。因此,对于荷U87MG人脑神经胶质瘤裸鼠,SPION-DMSA-99Tcm还不是一种理想的SPECT/MRI双模态显像剂。  相似文献   

4.
为制备纳米材料SPION-DMSA-RGD及其标记物SPION-DMSA-RGD-99 Tcm,探讨该标记物作为SPECT/MRI双模态显像剂的可能性,在水溶性纳米颗粒SPION-DMSA上连接c(RGDfC),得到了SPION-DMSA-RGD,并进行了结构表征。用99 Tcm对SPION-DMSA-RGD进行标记,并对该标记物进行了正常鼠和荷U87MG人脑神经胶质瘤裸鼠的生物分布研究,及荷U87MG人脑神经胶质瘤裸鼠的MRI和SPECT显像研究。研究结果表明,SPION-DMSA-RGD具有超顺磁性,99 Tcm标记率约为98%。正常鼠和荷U87MG人脑神经胶质瘤裸鼠的生物分布结果表明,SPION-DMSA-RGD-99 Tcm在血液中清除较快,在肝脏中摄取较高,在肿瘤中有摄取。荷U87MG人脑神经胶质瘤裸鼠的MRI和SPECT显像结果表明,SPION-DMSA-RGD和SPION-DMSA-RGD-99 Tcm的肿瘤主动靶向作用明显。以上结果提示,对于荷U87MG人脑神经胶质瘤裸鼠,SPION-DMSA-RGD-99 Tc m是一种SPECT/MRI双模态显像剂。  相似文献   

5.
固相分离材料是色层法从低比活度~(99)Mo料液中分离医用同位素~(99)Tc~m的关键。采用静态吸附和动态吸附淋洗实验,研究了聚酰胺树脂从~(99)Mo中吸附分离其衰变子体~(99)Tc~m的工艺,评价了其性能。结果表明:在NaOH浓度为3mol/L的钼酸钠溶液中,聚酰胺树脂能够在10s内选择性地吸附高锝酸根离子,并具有3.85mg/g的饱和吸附容量。2.0g装柱量的聚酰胺色层柱的漏穿体积约为70 mL,可用25 mL 3 mol/L NaOH溶液洗涤柱上残留的钼酸根离子,最后20mL水即可将吸附在聚酰胺色层柱上的锝淋洗下来。本研究为开发基于色层法的全自动~(99)Mo/~(99)Tc~m发生器装置提供了一种新型钼锝固相分离材料,其提取锝的淋洗效率为98%,洗脱液中钼的残留为0.6mg/L。  相似文献   

6.
本工作探讨了新型示踪剂99Tcm-HYNIC-3PEG4-E[c(RGDfK)]299Tcm-3PRGD2)用于胰腺癌的诊断价值及临床转化可行性。用免疫组化实验测定PANC-1胰腺癌细胞以及肿瘤组织中的整合素αvβ3的表达。将PANC-1胰腺癌细胞种植于BALB/c裸鼠肩部,建立合格的动物模型。以联肼尼克酰胺(HYNIC)作为双功能连接剂,采用无亚锡一步法制备99Tcm-3PRGD2。在0.5~6.0 h,每隔0.5 h行一次荷瘤鼠99Tcm-3PRGD2全身平面显像,观察全身分布情况,于肿瘤及健侧勾画感兴趣区(ROI, region of interest),计算肿瘤与本底(T/NT)的比值。对6例胰腺肿瘤患者行99Tcm-3PRGD2单光子发射的计算机断层显像(SPECT),评估对胰腺癌的检出率。结果表明:PANC-1胰腺癌细胞以及肿瘤组织中高表达整合素αvβ399Tcm-3PRGD2标记率大于99%。荷瘤鼠显像显示肿瘤对示踪剂摄取好,0.5 h时即可见肿瘤显影,1.5 h时T/NT达最大值,6.0 h时肿瘤仍可清晰显示。99Tcm-3PRGD2 SPECT显像可检出6例患者的胰腺肿瘤原发灶和肝转移灶,检出率为100%。99Tcm-3PRGD2是一种安全有效的示踪剂,特异性结合整合素αvβ3,99Tcm-3PRGD2 SPECT对胰腺癌的临床诊断具有潜在的应用前景。  相似文献   

7.
世界范围内医用99Tcm供应链仍很脆弱,开发基于非裂变产物99Mo的99Mo-99Tcm分离装置及工艺对于提高我国99Tcm供应能力十分重要。活性碳纤维(ACF)是性能优良的钼锝色层分离材料,可用于制备多柱选择性反向发生器(MSIG)结构的非裂变99Mo-99Tcm色层发生器。基于ACF改性和评价工作,利用重新设计的全自动非裂变99Mo-99Tcm发生器装置,开发三柱99Mo-99Tcm分离纯化工艺,并用该装置分离纯化获得的高锝[99Tcm]酸钠注射液进行MDP、MIBI药盒的标记。结果表明,非裂变99Mo-99Tcm发生器三柱分离工艺对99Mo-99Tcm模拟液中99Tcm收率可达78%,得到的高锝[99Tcm]酸钠注射液放化纯度和MDP、MIBI药盒标记率均符合《中国药典》要求。基于活性碳纤维开发的三柱反式选择型99Mo-99Tcm发生器有望用于从非裂变99Mo中提取99Tcm。  相似文献   

8.
In continuation of the investigation on the bithiophene structure as potential Aβ probes, two halogenated chalcone derivatives containing bithiophene moiety were designed and evaluated as imaging probes for Aβ plaques. In vitro fluorescence staining indicated that they could stain Aβ plaques in the brain sections of AD model mice specifically, in vitro binding assay further confirmed that they displayed high binding affinities to Aβ aggregates (Ki=2.33 nM and 0.88 nM). One radio-iodinated probe, 125I labeleled chalcone derivatives was obtained via iododestannylation reaction with high radiochemical yield and purity (>99%). Moreover, the125I-labeling compound displayed specific labeling of Aβ plaques in the brain sections of AD model mice with low background, and the specific labeling could be confirmed by thioflavin-S staining. In vivo biodistribution in normal mice indicated that the125I labeling compound exhibited low initial brain uptake (1.19%ID/g at 2 min) and rapid clearance. These preliminary results suggest that125I labeling compound may serve as novel Aβ imaging probe, although further modifications are needed to improve initial brain uptake.  相似文献   

9.
将具有肿瘤靶向性的精氨酸-精氨酸-亮氨酸(RRL)多肽与双功能螯合剂MAG3相连,摸索其螯合99Tcm的适宜标记条件并评价探针的体外稳定性。标记利用SnCl2还原法进行99Tcm标记,对影响标记的主要变量因素分别进行探究以获得适宜标记条件,采用纸层析法测定标记率和放射化学纯度。实验所得MAG3-RRL纯度为98.94%,适宜标记条件下,标记率为93.67%±1.10%,纯化后放射化学纯度为94.32%±0.19%(n=3)。99Tcm-MAG3-RRL在生理盐水和50%牛血清白蛋白(BSA)中放置,6 h内放射化学纯度均大于90%(n=3),在半胱氨酸溶液中的最高置换率为0.57%±0.21%,生理盐水对照为0.41%±0.04%(n=3,P>0.05)。99Tcm-MAG3-RRL的脂水分配系数为lg P=-0.15±0.01(n=3)。结果表明:MAG3可成功连接RRL多肽,并能进一步提高标记率;探针制备方法简单快速,体外稳定性好,为进一步的生物学实验提供了良好的基础。  相似文献   

10.
使用色层法从有载体~(99)Mo料液中提取医用同位素~(99)Tc~m是应对当前裂变~(99)Mo供应危机的新途径。本研究采用静态吸附实验和动态吸附淋洗实验,研究了利用活性碳纤维从~(99)Mo中吸附分离其衰变子体~(99)Tc~m的工艺和性能。结果表明:活性碳纤维可以在3mol/L NaOH体系的钼酸钠溶液中选择性吸附高锝酸根离子,静态吸附平衡时间约500s,吸附过程符合准二级动力学模型,饱和吸附容量为32.47mg/g。在动态吸附淋洗实验中,1.0g装柱量的活性碳纤维色层柱的漏穿体积为70mL,使用40mL水即可将活性碳纤维色层柱上吸附的锝淋洗下来。本实验结果表明,不使用有机溶剂即能用活性碳纤维色层柱完成钼和锝分离,锝的淋洗效率为98%,洗脱液中钼的残留为3.5mg/L。  相似文献   

11.
铀在生物体内的化学形态及分布是评价铀毒性的基础。文章通过尾静脉注射给药方式研究螯合剂对染铀小鼠体内铀分布的影响。通过建立包含主要体液金属离子、小分子配体及UO22+与螯合剂的热力学平衡模型,采用数值模拟方法研究UO22+在血液中的形态。实验结果表明:DTPA易与UO22+形成[(UO2)2(OH)DTPA]2-,对小鼠血液中的UO22+有明显的促排作用,但在促排的同时对小鼠的肾脏和骨骼有损伤;抗坏血酸对小鼠体内各组织器官的铀促排几乎无作用,但形成的[(UO2)2(OH)Ascorbate]2+会阻碍肾脏中U(Ⅵ)的代谢;NTA对小鼠体内各组织器官铀的促排作用小,并会促使体内出现固相(UO2)3(PO4)2·4H2O,对骨骼有较强的损伤作用,不适合作为铀的促排剂。  相似文献   

12.
合成诊断阿尔茨海默病(Alzheimer’s disease,AD)的Aβ斑块显像剂:7-甲氧基-2(6-[18F]-氟-吡啶-3-基)咪唑[2,1-β]-8-吡啶噻唑(18F-W372),不校正合成效率为(25.3±7.1)%(n=6),产品放化纯大于99.5%,比活度为659~721PBq/mol。 18F-W372小鼠体内分布实验显示,初始5min脑摄取为(4.36±1.44)%ID/g,清除较快,30min为(0.54±0.16)%ID/g,摄取比达到8,具有良好的生物学性能。急性毒性实验表明该药物安全可靠。在体试验显示药物注射40min,AD患者平均皮层/小脑吸收显著高于健康老年对照组。18F-W372是一种潜在的脑内Aβ淀粉显像剂。  相似文献   

13.
Most of human tumors over-express CXCR4. AMD3100, a nonpeptide antagonist for CXCR4 receptor, can be used for therapy of those tumors. It was found that metal ion complex, such as Cu2+, with AMD3100 enhanced its binding affinity to the receptor 10-fold higher as compared to AMD3100 alone. AMD3100 was synthesis from 3-aminopropyl ethylene diamine.99Tcm-AMD3100 was labeled directly. Biodistribution studies were carried out in NH mice. SPECT imaging was performed in Hep-G2 tumor bearing mouse. The synthetic yield was 5.8% from 3-aminopropyl ethylene diamine to AMD3100. The labeling yield of99Tcm-AMD3100 was over 98%. Biodistribution studies showed high accumulation of radiotracer in liver which had high-expression of CXCR4. SPECT imaging results showed that uptake in Hep-G2 tumor was high. The results showed that 99Tcm-AMD3100 was an attractive candidate for further development of SPECT radiotracer potentially suitable for CXCR4.  相似文献   

14.
The structural and kinetic studies of U(VI) complex with benzamidoxime(Hba) as ligand in CD3COCD3 have been studied by means of 1H and 13C NMR. The Hba molecule was found to coordinate to UO22+ in the form of anionic benzamidoximate (ba), and the number of ba coordinated to UO22+ was determined to be 3 by analyzing the chemical shift of 13C NMR signal for Hba in the presence of UO22+. The exchange rate constants(kex) of ba in [UO2(ba)3] were determined by the NMR line-broadening method. The kinetic parameters were obtained as follows: kex(25°C) = 3.1 × 103s−1, ΔH = 35.8 ± 3.5 KJ mol−1, and ΔS = −65 ± 13.7 J K−1 mol−1. The UV-visible absorption spectra of solutions containing UO22+ and Hba were also measured. The molar extinction coefficient of the complex was found to be extremely large compared with those of UO2(L)52+ (L = unidentate oxygen donor ligands) complexes. This is due to the strong electron withdrawing of UO22+ from Hba and suggests that an interaction between UO22+ and Hba is very strong. Such a high affinity of monomeric amidoxime to UO22+ reasonably explains the high adsorptibility of amidoxime resin to U(VI) species, and is considered to result in the high recovery of U(VI) species from sea water using amidoxime resin.  相似文献   

15.
在中国计量科学研究院电离辐射研究所的双管符合液闪分析仪上,开展放射性医用核素99Tcm比活度的实验测量,并深入研究CIEMAT/NIST方法中由于示踪核素3H比活度自身不确定度对实验结果带来的影响。实验结果表明,液闪系统的通用曲线(自由参数随淬灭指示参数tSIE变化的曲线)对示踪核素比活度较敏感,进而会影响到被测核素99Tcm的探测效率和比活度测量值。对于采用扩展不确定度为3%的3H示踪核素,当其比活度在其不确定度范围内发生变化时,最终测量得到的99Tcm比活度有近1%的变化。  相似文献   

16.
To study99Tcm-Annexin V distribution in inferior vena cava thrombus models of rabbits and uptake of99Tcm-Annexin V in fresh and old venous thrombus. Rabbits(n=15) were randomly grouped into 3 groups(the fresh thrombus group,old thrombus group,and control group). The rabbits of two thrombus groups developed inferior vena cava thrombus models by operations. The control group received sham operation. The fresh thrombus group and control group rabbits were injected99Tcm-Annexin V after operating 1d; the old thrombus group 14 d. After 1 h all rabbits were killed by injecting overdose pentobarbital sodium. The thrombus (or the inferior vena cava about 3cm below inferior pole of right kidney level in the control group rabbits),blood,thrombus area inferior vena cava,head lateral inferior vena cava (except the control group),thigh muscle,stomach,myocardium,pulmonary,liver,kidney,spleen,bone and small intestine were obtained from all group rabbits. The ex tissue and blood were weighed and measured by a Well-type detector. The percentage of the injected dose per gram of ex tissue (or blood) was calculated by the above data. The thrombus to blood,thrombus area inferior vena cava,head lateral inferior vena cava and thigh muscle ratios were calculated by percentage of the injected dose per gram of ex tissue (or blood) . The test was used to compare the fresh thrombus group and old thrombus group by SPSS 17.0. The percentage of the injected dose per gram of thrombi(0.018 94±0.002 16%ID/g)in the fresh thrombus group was higher than the old thrombus group (0.004 73±0.001 28%ID/g), P<0.05. The thrombus to blood,thrombus area inferior vena cava,head lateral inferior vena cava and muscle ratios (3.42±1.06,26.32±13.60,31.23±16.00,111.62±52.23) in the fresh thrombus group were higher than the old thrombus group(0.98±0.09,5.12±2.01,6.25±2.38,21.82±5.93) ,P<0.05 for all. All the thrombi of the fresh thrombus group were confirmed fresh mixed thrombi by Hematoxylin-eosin stains. All the thrombi of the old thrombus group were confirmed old mixed organized thrombi by Hematoxylin-eosin stains. 99Tcm-Annexin V may be used to venous thrombus imaging and discriminate fresh venous thrombus from old one by imaging.  相似文献   

17.
The structure of uranyl ion in 1-butyl-3-methylimidazolium nonafluorobutanesulfonate ionic liquid (BMINfO) has been studied with 1H- and 35Cl-NMR, Raman, and UV-visible spectroscopy. In the 1H-NMR spectrum of the BMINfO solution prepared by dissolving UO2(ClO4)2·5 6H2O, the signal of H2O coordinated to UO22+ was observed at 6.64 ppm at 50°C (free H2O in BMINfO: 3.1 ppm at 50°C), suggesting that the uranyl species exists as the aquo complex, [UO2(H2O)n]2+. The signal of the coordinated H2O disappears with heating at 120°C for 3 h under vacuum. This indicates the dehydration from [UO2(H2O)n]2+. On the other hand, the 35Cl-NMR signal of ClO4 as the counter anion of UO22+ was observed at 1011 ppm (vs. Cl in D2O) regardless of heating. This indicates that no ClO4 ion is in the first coordination sphere of UO22+. Furthermore, the UV-visible absorption spectra showed that the characteristic absorption bands due to UO22+ were sharpened with the dehydration. This means the simplification of the structure around UO22+. These results described above suggest that UO22+ in BMINfO has no ligand in its equatorial plane after the dehydration, i.e. UO22+ exists as a bare cation in this system.  相似文献   

18.
离子液体具有独特的物理化学性质,可以参与或影响两亲分子自组装。离子液体介质中的自组装研究所涉及的两亲分子多为有机化合物,而金属配合物在离子液体中的组装鲜有报道。另外,萃取剂正辛基苯基-N,N-二异丁基胺基甲酰基甲基氧化膦(CMPO)在1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺盐(C2mimNTf2)中萃取UO2+2时形成的萃合物结构组成有待深入研究。本工作探究了UO2(CMPO)3(NO3)2在C2mimNTf2中的组装行为。原位透射电镜(原位TEM)研究表明:UO2(CMPO)3(NO3)2在C2mimNTf2(含70μL水)中形成聚集体,冷冻刻蚀电镜(FF-TEM)显示该聚集体是胶束。此外,研究了CMPO-C2mimNTf2体系萃取UO2+2时形成的萃合物组成。离子色谱结果表明:萃取前后水相中NO-3浓度变化不大,电喷雾质谱(ESI-MS)上均为UO2(CMPO)3(NTf2)2的碎片离子峰,这些结果说明:CMPO-C2mimNTf2体系萃取UO2+2时形成的萃合物组成为UO2(CMPO)3(NTf2)2而非UO2(CMPO)3(NO3)2。这有助于深入了解金属配合物在离子液体中的组装行为,并对理解CMPO-C2mimNTf2体系萃取UO2+2的机理提供了重要参考。  相似文献   

19.
为了解铀酰离子在北山地下水中的吸附、扩散和迁移行为,利用地球化学计算软件PHREEQC,采用由OECD/NEA发布的最新铀的热力学数据,计算了铀在我国高放废物地质处置库重点研究区甘肃北山地下水中的种态分布,并分析了围岩中存在的方解石对铀溶解度的影响。计算结果表明,在北山地下水组成不变的前提下,在偏酸性条件下,铀主要以UO2F+、UO2SO4、UO22+、UO2F2和UO2(SO4)22-的形式存在,而在中性至弱碱性条件下,主要以 UO2(CO3)4-3、UO2(CO3)22-、UO2(OH)3-和UO2(OH)42-的形式存在。我国计划建造的高放废物处置库的设计深度为地下500~1000m,其水岩体系一般呈弱碱性。在这样的弱碱性水岩体系中,以阴离子形式存在的铀酰配合物具有较强的可移动性。当地下水的pH=7.56时,在Eh<24mV的条件下,铀主要以沥青铀矿的形式存在,而在更高的Eh条件下,则主要以UO22+与CO32-和OH-形成的阴离子配合物的形式存在。当地下水与空气接触时,O2的存在会使Eh升高,此时铀的主要存在种态为UO22+及其各种配合物。当围岩体系中存在方解石时,在pH<8.0的条件下,铀在地下水中的溶解度会显著提高,而在更高pH条件下,方解石对铀的溶解度无明显影响。  相似文献   

20.
99Tcm是核医学临床诊断应用最为广泛的放射性核素,其使用量占所有诊断用放射性核素的70%左右。99Tcm在临床上主要由其母体核素99Mo衰变通过99Mo-99Tcm发生器获得。中国从20世纪60年代末开始医用99Mo与99Mo-99Tcm发生器的研制工作,并取得了十分瞩目的成就。本文对我国医用99Mo及99Mo-99Tcm发生器的发展进行了简要回顾,分析了我国在99Mo及99Mo-99Tcm发生器生产方面存在的问题,并对其今后的发展提出了建议,以期促进国内放射性同位素技术进一步的发展。  相似文献   

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