共查询到20条相似文献,搜索用时 78 毫秒
1.
Dr. Boris D. Zlatopolskiy Johannes Zischler Elizaveta A. Urusova Priv.-Doz. Dr. Heike Endepols Dr. Elena Kordys Dr. Holm Frauendorf Prof. Dr. Felix M. Mottaghy Prof. Dr. Bernd Neumaier 《ChemistryOpen》2015,4(4):394-462
Invited for this months cover picture is the group of Professor Bernd Neumaier at the Institute of Radiochemistry and Experimental Molecular Imaging at the University Clinic of Cologne. The cover picture shows the differences in brain metabolism of a healthy young and a healthy old subject, as well as a patient suffering from Parkinsons disease (left to right) uncovered by 6-[18F]FDOPA-positron emission tomography (PET). Morbus Parkinson occurs when nerve cells that produce dopamine begin to die. The shortage of dopamine leads to movement problems in affected individuals. 6-[18F]FDOPA is extensively used to evaluate the progression of Parkinsons disease. Bold stick projections of this PET tracer, as well as a neuronal network, are seen in the background. Unfortunately, conventional procedures to produce 6-[18F]FDOPA are cumbersome. Thus, several recent developments aim at the simplification of this radiosynthesis. In our work, we studied the applicability of the recently reported Ni-mediated radiofluorination approach for daily routine production of 6-[18F]FDOPA. For more details, see the Full Paper on p. 457 ff. 相似文献
2.
Potential of electrophilic and nucleophilic methods of radiofluorination in the synthesis of fluorine-18-labeled fluorinated amino acid analogs, radiotracers for positron emission tomography (PET), is considered. The synthesis of 6-L-[18F]FDOPA ((S)-2-amino-3-(6-[18F]fluoro-3,4-dihydroxyphenyl)propionic acid) was used as an example to discuss new elaborations in this field directed on both the improvement of already existing methods and the development of fundamentally new approaches to the introduction of a fluorine-18 label into the nonactivated aromatic ring of amino acids using nucleophilic methods. 相似文献
3.
Alexander Popkov Jiří Hanusek Jiří Čermák Vratislav Langer Robert Jirásko Michal Holčapek Milan Nádvorník 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(3):621-626
In this communication the evaluation of eleven new metallocomplex alanine synthons bearing C2-symmetric benzyl groups with electron-donating and electron-withdrawing substituents is described. α-Methylated glycine synthons (alanine complexes) were evaluated alongside alanine synthons in order to obtain a deeper understanding of the relationship between their structures and stereochemistry of monoalkylated products and to choose several candidates for their further tests for stereospecific preparation of 6-[18F]FDOPA. Glycine-derived analogues of the complexes 3–5 are the best candidates for the development of a 6-[18F]FDOPA preparation procedure. In the model epimerisation reaction they demonstrated the best performance, much better compared to the previously described compound 2. Complexes 3, 5 and 8 are the best in asymmetric preparation of β-13C monolabelled α-aminoisobutyric acid. They have to be tested in the preparation of α-methyl amino acids like 6-[18F]-α-methylDOPA and 2-[18F]-α-methyltyrosine. 相似文献
4.
A. Al-Labadi K.-P. Zeller H.-J. Machulla 《Journal of Radioanalytical and Nuclear Chemistry》2006,270(2):313-318
Summary Fluorodehalogenation reactions were used to prepare 6-[18F]fluoroveratraldehyde. The synthesis of 6-[18F]fluoroveratraldehyde is the first step in the multi-step synthesis of the clinically important tracer 6-[18F]fluoro-L-dopa. In the literature yields ranging from 20-50% are reported when using nitro and trimethylammoniumtriflate
precursors. However, no data exist concerning the use of different leaving groups such as halogens. Therefore, 6-bromo, 6-chloro
and 6-fluoroveratraldehyde were tested in the nucleophilic aromatic substitution by [18F]fluoride. In DMF, 6-[18F]fluoroveratraldehyde was obtained with radiochemical yields of (57±1.0)% and (66±3.6)% in 20 minutes at 160 °C using 50
mg/ml bromo and chloro precursor, respectively. The fluoro precursor gave a radiochemical yield of (87±0.8)% at 140 °C. Temperature,
solvent and concentration strongly affected the 18F-labeling. Among the halogens the ability as a leaving group was F>>Cl>Br. The halogenated veratraldehydes provide a good
alternative for the synthesis of ca and nca 6-[18F]fluoroveratraldehyde, as the first step of the synthesis for [18F]FDOPA since they are inexpensive, commercially available, stable, sustain hard conditions in the labeling step, and give
yields better or equal to other precursors previously reported. 相似文献
5.
Duanzhi Yin Lan Zhang Ganghua Tang Xiaolan Tang Yongxian Wang 《Journal of Radioanalytical and Nuclear Chemistry》2003,257(1):179-185
6-[18F]Fluoro-L-Dopa (6-FDOPA) is the analogue of L-Dopa, the biosynthesis precursor for dopamine. As a PET tracer, it was widely applied for the presynaptic dopamine function studies in human brain. The application of a chiral phase-transfer-catalyst (PTC) in enantioselective synthesis of N.C.A. 6-[18F]Fluoro-L-Dopa has been developed recently. An improved procedure was described in this study. The labeling precursor (6-Trimethylammoniumveratraldehyde Triflate) and PTC (O-Allyl-N-(9)-anthracenylcinchonidinium Bromide) were synthesized. A successful synthesis route was developed for the preparation of 6-[18F]Fluoro-L-Dopa with high radiochemical yields (4-9%, decay uncorrected) and short synthesis time(80min). The radiochemical purity was over 99% and no D-isomer was detected by HPLC analysis using a chiral mobile phase. 相似文献
6.
M. C. Freitas I. Dionísio D. G. Beasley S. M. Almeida H. M. Dung C. Repolho A. M. G. Pacheco A. Caseiro C. A. Pio C. Alves 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(1):15-20
3-(4-[18F]fluorobenzyl)-8-hydroxy-1,2,3,4-tetrahydrochromeno[3,4-c]pyridin-5-one ([18F]FHTP) was in vitro and in vivo evaluated as a putative dopamine D4 receptor radioligand. Its inhibition constant (K
i
) for cloned human dopamine D4.2 receptor was determined to be 2.9 nM and it displayed a 2000-fold D4-selectivity over the D2long subtype. Its partition coefficient (logP) was measured to be 1.11. Biodistribution, blocking distribution and metabolism studies in rats demonstrated that the specific
distribution of [18F]FHTP in brain regions, suggesting that [18F]FHTP may be a suitable PET imaging agent for in vivo studies of the dopamine D4 receptor. 相似文献
7.
Amanda J. Boyle Emily Murrell Junchao Tong Christin Schifani Andrea Narvaez Melinda Wuest Frederick West Frank Wuest Neil Vasdev 《Molecules (Basel, Switzerland)》2022,27(23)
Fluorine-18 labeled 6-fluoro-6-deoxy-D-fructose (6-[18F]FDF) targets the fructose-preferred facilitative hexose transporter GLUT5, which is expressed predominantly in brain microglia and activated in response to inflammatory stimuli. We hypothesize that 6-[18F]FDF will specifically image microglia following neuroinflammatory insult. 6-[18F]FDF and, for comparison, [18F]FDG were evaluated in unilateral intra-striatal lipopolysaccharide (LPS)-injected male and female rats (50 µg/animal) by longitudinal dynamic PET imaging in vivo. In LPS-injected rats, increased accumulation of 6-[18F]FDF was observed at 48 h post-LPS injection, with plateaued uptake (60–120 min) that was significantly higher in the ipsilateral vs. contralateral striatum (0.985 ± 0.047 and 0.819 ± 0.033 SUV, respectively; p = 0.002, n = 4M/3F). The ipsilateral–contralateral difference in striatal 6-[18F]FDF uptake expressed as binding potential (BPSRTM) peaked at 48 h (0.19 ± 0.11) and was significantly decreased at one and two weeks. In contrast, increased [18F]FDG uptake in the ipsilateral striatum was highest at one week post-LPS injection (BPSRTM = 0.25 ± 0.06, n = 4M). Iba-1 and GFAP immunohistochemistry confirmed LPS-induced activation of microglia and astrocytes, respectively, in ipsilateral striatum. This proof-of-concept study revealed an early response of 6-[18F]FDF to neuroinflammatory stimuli in rat brain. 6-[18F]FDF represents a potential PET radiotracer for imaging microglial GLUT5 density in brain with applications in neuroinflammatory and neurodegenerative diseases. 相似文献
8.
Viktoriya V. Orlovskaya Austin S. Craig Olga S. Fedorova Olga F. Kuznetsova Bernd Neumaier Raisa N. Krasikova Boris D. Zlatopolskiy 《Molecules (Basel, Switzerland)》2021,26(18)
6-l-[18F]Fluoro-m-tyrosine (6-l-[18F]FMT) represents a valuable alternative to 6-l-[18F]FDOPA which is conventionally used for the diagnosis and staging of Parkinson’s disease. However, clinical applications of 6-l-[18F]FMT have been limited by the paucity of practical production methods for its automated production. Herein we describe the practical preparation of 6-l-[18F]FMT using alcohol-enhanced Cu-mediated radiofluorination of Bpin-substituted chiral Ni(II) complex in the presence of non-basic Bu4ONTf using a volatile iPrOH/MeCN mixture as reaction solvent. A simple and fast radiolabeling procedure afforded the tracer in 20.0 ± 3.0% activity yield within 70 min. The developed method was directly implemented onto a modified TracerLab FX C Pro platform originally designed for 11C-labeling. This method enables an uncomplicated switch between 11C- and 18F-labeling. The simplicity of the developed procedure enables its easy adaptation to other commercially available remote-controlled synthesis units and paves the way for a widespread application of 6-l-[18F]FMT in the clinic. 相似文献
9.
Damiano Librizzi Nicole Cabanel Maxim Zavorotnyy Elisabeth Riehl Tilo Kircher Markus Luster Behrooz Hooshyar Yousefi 《Molecules (Basel, Switzerland)》2021,26(5)
PET of β-Amyloid plaques (Aβ) using [18F]florbetaben ([18F]FBB) and [18F]fluorodeoxyglucose ([18F]FDG) increasingly aid clinicians in early diagnosis of dementia, including Alzheimer’s disease (AD), frontotemporal disease, dementia with Lewy bodies, and vascular dementia. The aim of this retrospective analysis was to evaluate clinical relevance of [18F]FBB, [18F]FDG PET and complimentary CSF measurements in patients with suspected dementia. In this study, 40 patients with clinically suspected or history of dementia underwent (1) measurement of Aβ peptides, total tau, and p-tau protein levels in the cerebrospinal fluid (CSF) compared with healthy controls (HC); (2) clinical and neuropsychological assessment, which included Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological assessment battery (CERAD-NAB); (3) [18F]FBB and [18F]FDG PET imaging within an average of 3 weeks. The subjects were within 15 days stratified using PET, CSF measurements as HC, mild cognitive impaired (MCI) and dementia including Alzheimer´s disease. The predictive dementia-related cognitive decline values were supporting the measurements. PET images were evaluated visually and quantitatively using standard uptake value ratios (SUVR). Twenty-one (52.5%) subjects were amyloid-positive (Aβ+), with a median neocortical SUVR of 1.80 for AD versus 1.20 relative to the respective 19 (47.5 %) amyloid-negative (Aβ-) subjects. Moreover, the [18F]FDG and [18F]FBB confirmed within a sub-group of 10 patients a good complimentary role by correlation between amyloid pathology and brain glucose metabolism in 8 out of 10 subjects. The results suggest the clinical relevance for [18F]FBB combined with [18F]FDG PET retention and CFS measurements serving the management of our patients with dementia. Therefore, [18F]FBB combined with [18F]FDG PET is a helpful tool for differential diagnosis, and supports the patients’ management as well as treatment. 相似文献
10.
Sheng Liang Zhengping Chen Yufei Ma Jun Guo Hui Wang 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):1969-1972
2β-Carbomethoxy-3β-(4-chlorophenyl)-8-(2-[18F]fluoroethyl)nortropane ([18F]-FECNT) is a potential dopamine transporter PET imaging agent. However, its current radio-synthesis is tedious and time consuming. In this article, we reported a fully automatic method for the synthesis of [18F] FECNT through only one step, using a TRACERlab FXN module, with decay corrected radiochemical yield of 25 ± 5 % (n = 5). The total synthesis time was 50–55 min. The synthesized [18F]FECNT was evaluated in vivo in Parkinson’s disease model rats. 相似文献
11.
Peter Roselt Carleen Cullinane Wayne Noonan Hassan Elsaidi Peter Eu Leonard I. Wiebe 《Molecules (Basel, Switzerland)》2020,25(23)
Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E’s biodistributions and pharmacokinetics via non-invasive temporal imaging. (R)-6-(3-[18F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([18F]F-γ-T-3) was prepared for this purpose. [18F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di-O-tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [18F]fluoride in DMF/K222. Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [18F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [18F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [18F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues. 相似文献
12.
M. Patt A. Schildan H. Barthel G. Becker M. H. Schultze-Mosgau B. Rohde C. Reininger O. Sabri 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(3):557-562
[18F]Florbetaben ([18F]BAY 94-9172) is a promising β-amyloid (Aβ) targeted PET-tracer currently in late stage clinical development. [18F]Florbetaben can assist in the more accurate diagnosis of Alzheimer’s Disease (AD) by non-invasive, in vivo detection of
Aβ in the brain. To determine the arterial input function of the PET tracer—as part of a proof of mechanism (PoM) study—arterial
samples were drawn from all subjects at predefined time points post injection (p.i.), and the proportion of unchanged tracer
[18F]Florbetaben was determined by HPLC analysis. Plasma metabolite profiles were investigated following intravenous administration
of 300 MBq (±60 MBq) of [18F]Florbetaben to both, patients with AD and healthy controls (HCs), and various methods for processing the blood samples were
evaluated. Addition of acetonitrile to plasma samples (obtained from whole blood by centrifugation) and precipitation of proteins
resulted in a recovery of more than 90% of the initial radioactivity in the supernatants. High Performance Liquid Chromatography
using a polymer-based column (PRP-1) in conjunction with gradient elution was found to be a suitable method of metabolite
analysis of [18F]Florbetaben. HPLC analyses indicated that [18F]Florbetaben is rapidly metabolized in vivo with an estimated initial half-life of about 6 min. A polar metabolite fraction,
consisting presumably of more than one component, and (to a smaller extent) of the demethylated derivative of [18F]Florbetaben were time-dependently detected in plasma. 相似文献
13.
Viktor A. Ilin Elena V. Pyzhik Anton B. Balakhonov Maksim A. Kiryushin Evgeniya V. Shcherbatova Andrey A. Kuznetsov Pavel A. Kostin Andrey V. Golovin Vladimir A. Korshun Vladimir A. Brylev Kseniya A. Sapozhnikova Alexey M. Kopylov Galina V. Pavlova Igor N. Pronin 《Molecules (Basel, Switzerland)》2023,28(1)
Central nervous system tumors related to gliomas are of neuroectodermal origin and cover about 30% of all primary brain tumors. Glioma is not susceptible to any therapy and surgical attack remains one of the main approaches to its treatment. Preoperative tumor imaging methods, such as positron emission tomography (PET), are currently used to distinguish malignant tissue to increase the accuracy of glioma removal. However, PET is lacking a specific visualization of cells possessing certain molecular markers. Here, we report an application of aptamers to enhancing specificity in imaging tumor cells bearing the epidermal growth factor receptor (EGFR). Glioblastoma is characterized by increased EGFR expression, as well as mutations of this receptor associated with active division, migration, and adhesion of tumor cells. Since 2021, EGFR has been included into the WHO classification of gliomas as a molecular genetic marker. To obtain conjugates of aptamers GR20 and GOL1-specific to EGFR, a 4-[18F]fluorobenzylazide radiotracer was used as a synthon. For the production of the synthon, a method of automatic synthesis on an Eckert & Ziegler research module was adapted and modified using spirocyclic iodonium ylide as a precursor. Conjugation of 4-[18F]fluorobenzylazide and alkyne-modified aptamers was carried out using Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) with/without the TBTA ligand. As a result, it was possible to obtain 18F-labelled conjugates with 97% radiochemical purity for [18F]FB-GR20 and 98% for [18F]FB-GOL1. The obtained conjugates can be used for further studies in PET analysis on model animals with grafted glioblastoma. 相似文献
14.
Shivashankar Khanapur Fui Fong Yong Siddesh V. Hartimath Lingfan Jiang Boominathan Ramasamy Peter Cheng Pradeep Narayanaswamy Julian L. Goggi Edward George Robins 《Molecules (Basel, Switzerland)》2021,26(6)
Positron emission tomography (PET) imaging of activated T-cells with N-(4-[18F]fluorobenzoyl)-interleukin-2 ([18F]FB-IL-2) may be a promising tool for patient management to aid in the assessment of clinical responses to immune therapeutics. Unfortunately, existing radiosynthetic methods are very low yielding due to complex and time-consuming chemical processes. Herein, we report an improved method for the synthesis of [18F]FB-IL-2, which reduces synthesis time and improves radiochemical yield. With this optimized approach, [18F]FB-IL-2 was prepared with a non-decay-corrected radiochemical yield of 3.8 ± 0.7% from [18F]fluoride, 3.8 times higher than previously reported methods. In vitro experiments showed that the radiotracer was stable with good radiochemical purity (>95%), confirmed its identity and showed preferential binding to activated mouse peripheral blood mononuclear cells. Dynamic PET imaging and ex vivo biodistribution studies in naïve Balb/c mice showed organ distribution and kinetics comparable to earlier published data on [18F]FB-IL-2. Significant improvements in the radiochemical manufacture of [18F]FB-IL-2 facilitates access to this promising PET imaging radiopharmaceutical, which may, in turn, provide useful insights into different tumour phenotypes and a greater understanding of the cellular nature and differential immune microenvironments that are critical to understand and develop new treatments for cancers. 相似文献
15.
Ralf SchirrmacherPhilippe Lucas Esther SchirrmacherBjörn Wängler Carmen Wängler 《Tetrahedron letters》2011,52(16):1973-1976
Strained tricyclic ring systems such as epoxides are rarely used as precursors for the introduction of anionic fluorine-18 into organic compounds intended for positron emission tomography (PET). Here we report the alpha selective ring opening of epoxides for the introduction of fluorine-18 into small as well as larger biomolecules via 1- and 2-step protocols. [18F]fluoromisonidazole ([18F]MISO), a tracer for hypoxia imaging, and the tumor targeting peptide Tyr3-octreotate (TATE) were radiolabeled using epoxide opening reactions. In the latter case, the new prosthetic labeling synthon 4-(3-[18F]fluoro-2-hydroxypropoxy)benzaldehyde ([18F]FPB) has been used for 18F-introduction. 相似文献
16.
Dr. Matthew Tredwell Dr. Sean M. Preshlock Nicholas J. Taylor Dr. Stefan Gruber Dr. Mickael Huiban Dr. Jan Passchier Dr. Joël Mercier Dr. Christophe Génicot Prof. Véronique Gouverneur 《Angewandte Chemie (International ed. in English)》2014,53(30):7751-7755
Molecules labeled with fluorine‐18 are used as radiotracers for positron emission tomography. An important challenge is the labeling of arenes not amenable to aromatic nucleophilic substitution (SNAr) with [18F]F?. In the ideal case, the 18F fluorination of these substrates would be performed through reaction of [18F]KF with shelf‐stable readily available precursors using a broadly applicable method suitable for automation. Herein, we describe the realization of these requirements with the production of 18F arenes from pinacol‐derived aryl boronic esters (arylBPin) upon treatment with [18F]KF/K222 and [Cu(OTf)2(py)4] (OTf=trifluoromethanesulfonate, py=pyridine). This method tolerates electron‐poor and electron‐rich arenes and various functional groups, and allows access to 6‐[18F]fluoro‐L ‐DOPA, 6‐[18F]fluoro‐m‐tyrosine, and the translocator protein (TSPO) PET ligand [18F]DAA1106. 相似文献
17.
[18F]-3′-deoxy-3′-fluorothymidine ([18F]FLT) is an established positron emission tomograph (PET)—radiopharmaceutical to study cell-proliferation rate in tumors.
Very low practical yield, uncertain and time-consuming high performance liquid chromatography (HPLC) purification, are the
main obstacles for the routine use of [18F]FLT in clinical PET. To obviate these difficulties, we have developed a fully automated radiosynthesis procedure for [18F]FLT using 5′-O-(4,4′-dimethoxytriphenylmethyl)-2,3′-anhydro-thymidine (DMTThy) and simplified single neutral alumina column purification.
The [18F]FLT yield was 8.48 ± 0.93% (n = 5) (without radioactive decay correction) in a synthesis time of 68 ± 3 min. The radiochemical purity was greater than
95% as confirmed by analytical HPLC using reference standard FLT and also free of non-radioactive impurity. Soluble aluminum
in the final product was much below the permissible limits. Di-methyl sulfoxide (DMSO), the reaction medium, could be detected
in the final product in trace amounts, well below the permissible levels. The synthesized [18F]FLT was sterile and bacterial endotoxin free by appropriate tests. PET imaging study in normal rabbits showed distinct localization
of [18F]FLT in organs having rapid cell division rate like bone marrow, guts and snout and the excretion was through the renal route.
There were no significant uptakes in bone and brain. The former finding confirms the in vivo stability of the [18F]FLT. This simplified radiosynthesis procedure can easily be adapted in any commercial or indigenous [18F]FDG synthesis module for routine [18F]FLT synthesis without the need of additional automation for HPLC purification. 相似文献
18.
Synthesis and Evaluation of [18F]‐Ammonium BODIPY Dyes as Potential Positron Emission Tomography Agents for Myocardial Perfusion Imaging 下载免费PDF全文
Dr. Kantapat Chansaenpak Dr. Hui Wang Mengzhe Wang Dr. Benjamin Giglio Dr. Xiaofeng Ma Prof. Dr. Hong Yuan Prof. Dr. Shuo Hu Prof. Dr. Zhanhong Wu Prof. Dr. Zibo Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):12122-12129
Recently, we demonstrated the potential of a [18F]‐trimethylammonium BODIPY dye for cardiac imaging. This is the first example of the use of the [18F]‐ammonium BODIPY dye for positron emission tomography (PET) myocardial perfusion imaging (MPI). In this report, we extend our study to other ammonium BODIPY dyes with different nitrogen substituents. These novel ammonium BODIPY dyes were successfully prepared and radiolabeled by the SnCl4‐assisted 18F–19F isotopic exchange method. The microPET results and the biodistribution data reveal that nitrogen substituent changes have a significant effect on the in vivo and pharmacological properties of the tracers. Of the novel [18F]‐ammonium BODIPY dyes prepared in this work, the [18F]‐dimethylethylammonium BODIPY is superior in terms of myocardium uptake and PET imaging contrast. These results support our hypothesis that the ammonium BODIPY dyes have a great potential for use as PET/optical dual‐modality MPI probes. 相似文献
19.
O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET), a fluorine-18 labeled analogue of tyrosine, has been synthesized and biologically evaluated in tumor-bearing mice.
The whole synthesis procedure is completed within 50 min. The radiochemical yield is about 40% (no decay corrected) and radiochemical
purity more than 97% after simplified solid phase extraction. [18F]FET shows rapid, high uptake and long retention in the tumor as well as low uptake in the brain. The ratios of tumor-to-muscle
(T/M) and tumor-to-blood (T/B) of [18F]FET are similar to those of [18F]FDG, but the ratios of tumor-to-brain (T/Br) are 2–3 times higher than that of [18F]FDG. Autoradiography of [18F]FET demonstrates a remarkable accumulation in melanoma with high contrast. It appears to be a probable competitive candidate
for melanoma imaging with PET.
Supported by the Knowledge Innovation Project of Chinese Academy of Sciences (No. KJCX1-SW-08) and the National Natural Science
Foundation of China (Grant No. 30371634) 相似文献
20.
Anthony-David T. Campoy Christopher Liang Reisha M. Ladwa Krystal K. Patel Ishani H. Patel Jogeshwar Mukherjee 《Molecules (Basel, Switzerland)》2021,26(23)
We report [18F]nifene binding to α4β2* nicotinic acetylcholinergic receptors (nAChRs) in Parkinson’s disease (PD). The study used transgenic Hualpha-Syn(A53T) PD mouse model of α-synucleinopathy for PET/CT studies in vivo and autoradiography in vitro. Additionally, postmortem human PD brain sections comprising of anterior cingulate were used in vitro to assess translation to human studies. Because the small size of mice brain poses challenges for PET imaging, improved methods for radiosynthesis of [18F]nifene and simplified PET/CT procedures in mice were developed by comparing intravenous (IV) and intraperitoneal (IP) administered [18F]nifene. An optimal PET/CT imaging time of 30–60 min post injection of [18F]nifene was established to provide thalamus to cerebellum ratio of 2.5 (with IV) and 2 (with IP). Transgenic Hualpha-Syn(A53T) mice brain slices exhibited 20–35% decrease while in vivo a 20–30% decrease of [18F]nifene was observed. Lewy bodies and α-synuclein aggregates were confirmed in human PD brain sections which lowered the [18F]nifene binding by more than 50% in anterior cingulate. Thus [18F]nifene offers a valuable tool for PET imaging studies of PD. 相似文献