The metabolic alterations in tumors make it possible to visualize the latter by means of positron emission tomography, enabling diagnosis and providing metabolic information. The alanine serine cysteine transporter‐2 (ASCT‐2) is the main transporter of glutamine and is upregulated in several tumors. Therefore, a good positron emission tracer targeting this transport protein would have substantial value

As part of a medicinal chemistry program aimed at developing a leukotriene C4 synthase inhibitor for the treatment of asthma, two tritium labeled and one stable isotope labeled compounds were required. The synthesis of the tritium labeled compounds used a standard bromination-tritiodehalogentation approach. One of the tritium labeled compounds was observed to exchange its tritium label slowly with

No abstract is available for this article.

In this paper, we disclose a new strategy for the radio-synthesis of [18 F]PARPi from the corresponding, boc-protected, nitro-precursor. Using a two-step procedure, [18 F]PARPi could be isolated in radiochemical yields up to 9.6%. The reaction proceeds via an efficient one-pot, two-step process, allowing for simplification over previous methods that require complex multi-step, multi-pot strategies

Prostate-specific membrane antigen (PSMA)-based radioligands for positron emission tomography (PET)/computed tomography (CT) studies represent the gold standard for detection of recurrent prostate cancer (PCa). [68 Ga]PSMA-HBED-CC is a PET radiotracer suitable for detection of PCa, and its clinical use has become widespread over the last few years. In this contribution we detail our GMP-compliant production

Here we describe the development of an in-house-built device for the fully automated multi-step synthesis of the cannabinoid CB1 receptor imaging tracer (3R,5R)-5-(3-([18 F]fluoromethoxy-d2 )phenyl)-3-(((R)-1-phenylethyl)amino)-1-(4-(trifluoromethyl)phenyl)pyrrolidin-2-one ([18 F]FMPEP-d2 ), following Good Manufacturing Practices. The device is interfaced to a HPLC and a sterile filtration unit in

No abstract is available for this article.

The one step tritiation of S-(4-nitrobenzyl)-6-thioinosine is described with characterization of the product by tritium NMR as well as mass spectrometry. The storage, stability and repurification of [benzyl methylene-3 H]S-(4-nitrobenzyl)-6-thioinosine are also discussed.

No abstract is available for this article.

The one-step synthesis of [14 C]potassium cyanate from [14 C]urea is described with product characterization by gravimetric specific activity as well as a novel TLC system. The storage, stability, and repurification of [14 C]potassium cyanate are also discussed.

An automated radiosynthesis of carbon-11 positron emission tomography radiotracer [11 C]UCB-J for imaging the synaptic density biomarker synaptic vesicle glycoprotein SV2A was established using Synthra RNPlus synthesizer. Commercially available trifluoroborate UCB-J analogue was used as a radiolabelling precursor, and the desired radiolabelled product was isolated in 11 ± 2% (n = 7) nondecay corrected

Herein we report an efficient radiolabeling of a 18 F-fluorinated derivative of dual inhibitor GW2580, with its subsequent evaluation as a positron emission tomography (PET) tracer candidate for imaging of two neuroreceptor targets implicated in the pathophysiology of neurodegeneration: tropomyosin receptor kinases (TrkB/C) and colony stimulating factor receptor (CSF-1R). [18 F]FOMPyD was synthesized

Prostate-specific membrane antigen (PSMA) is the most promising target for radioligand therapy of prostate cancer. The aim of this study was to prepare a small molecular ligand p-SCN-Bn-TCMC-PSMA (NG001) and compare it with the commonly used DOTA-based PSMA-617. The PSMA-targeting ability of the 212 Pb-labelled ligands was evaluated using PSMA-positive C4-2 human prostate cancer cells. Lead-212 is

The initial discovery and establishment of a family of novel iridium catalysts possessing N-heterocyclic carbene units alongside bulky phosphine ligands allowed selected substrates to be labelled using deuterium or tritium gas at desirably low catalyst loadings via an ortho-directed C-H insertion process. Such a method has broad applicability and offers distinct advantages within the pharmaceutical

The serotonin 7 (5-HT7 ) receptor is suggested to be involved in a broad variety of CNS disorders, but very few in vivo tools exist to study this important target. Molecular imaging with positron emission tomography (PET) would enable an in vivo characterization of the 5-HT7 receptor. However, no clinical PET radiotracer exists for this receptor, and thus we aimed to develop such a tracer. In this

The combined action of shikonin and silver nanoparticles (AgNPs) for apoptosis in human cancer cells has not been elucidated. Hence, we investigated the synergistic combinatorial effect of shikonin and AgNPs in human lung cancer cells. Shikonin was used as a reducing and capping agent for AgNPs synthesis as a green method avoiding the hazards of chemical methods. Radiolabeling of shikonin-AgNPs with

Synthesis of carboxy-polyethylene glycol-amine (CA (PEG)n ) via oxa-Michael addition of amino-polyethylene glycols to either acrylates or propiolates was investigated. Compared with the oxa-Michael addition to acrylates, the corresponding addition to propiolates was found to proceed under mild reaction conditions and afford the adducts in high yields from a broad scope of substrates. A two-step efficient

Azure-A is one of the phenothiazines (PTZs) derivatives which for decades have been used as antipsychotic drugs due to good lipophilic characteristics which enable them to pass through the blood brain barrier (BBB), besides the important property of enabeling investigation of the pathological forms of aggregated tau protein found in the neurons of the central nervous system. Radioiodination of Azure-A

Parkinson disease (PD) is a neurodegenerative disorder characterized by the accumulation of α-synuclein into Lewy bodies. 3-Benzylidine-indolin-2-one represents a class of compounds, which are known to inhibit the accumulation of α-synuclein. In this paper, we report the synthesis of [13 C] and [15 N] labelled 1-benzyl-(Z)-3-(benzylidene)indolin-2-one from commercially available [13 C2 ]-chloroacetic

An 18 F-labelled human epidermal growth factor receptor (HER2) receptor binding radiotracer is a potential tool to non-invasively identify HER2 positive tumour lesions in subjects with recurrent metastatic breast cancer. Having explored the manual radiochemistry to conjugate the Affibody molecule ZHER2:2891 with [18 F]4-fluorobenzaldehyde, we have developed and optimised a full protocol for the automated

The clinical impact and accessibility of 99m Tc tracers for cancer diagnosis would be greatly enhanced by the availability of a new, simple, and easy labeling process and radiopharmaceuticals. 5-Fluorouracil is an antitumor drug, which has played an important role for the treatment of breast carcinoma. In the present study, a new derivative of 5-Fluorouracil was synthesized as (1-[{1'-(1''-deoxy-2''

15 N-labelled pyridines are liquid- and solid-state nuclear magnetic resonance (NMR) probes for chemical and biological environments because their 15 N chemical shifts are sensitive to hydrogen-bond and protonation states. By variation of the type and number of substituents, different target pyridines can be synthesized exhibiting different pKa values and molecular volumes. Various synthetic routes

The gastrin-releasing peptide receptor (GRPR) is overexpressed in prostate cancer and other solid malignancies. Following up on our work on [68 Ga]Ga-ProBOMB1 that had better imaging characteristics than [68 Ga]Ga-NeoBOMB1, we investigated the effects of substituting 68 Ga for 177 Lu to determine if the resulting radiopharmaceuticals could be used with a therapeutic aim. We radiolabeled the bombesin

Labeling agents with radioisotopes or fluorescent dyes are useful for investigating the biodistributions of biologically active proteins and peptides. Compared with molecular imaging with a single modality, dual imaging probes provide complementary information for each modality. The development of a dual radioisotope/fluorescence agent for protein labeling would thus be valuable for both preclinical

Amyvid (florbetapir f18, [18 F]AV-45, [18 F]5) was the first FDA-approved positron emission tomography imaging agent targeting β-amyloid (Aβ) plaques for assisting the diagnosis of Alzheimer disease. This work aimed to improve the [18 F]AV-45 ([18 F]5) preparation by using solid-phase extraction (SPE) purification. [18 F]AV-45 ([18 F]5) was synthesized by direct nucleophilic radiofluorination of O-tosylated

System xc- (Sxc -) has emerged as a new biological target for PET studies to detect oxidative and excitotoxic stress. Notably, applications have, thus far, been limited to tumour imaging although Sxc - ) may play a major role in neurodegeneration. The synthesis procedures of tosylate precursor and its translation to Sxc - PET tracer 5[18F]fluoro-L-amino suberate by manual and automated radiosyntheses

In this practitioner protocol, the radiochemical synthesis of [11 C]CPPC is described in detail, and a quality control summary of three validation productions is presented. The results indicate that the radiotracer product can be produced in good radiochemical yield (> 60 mCi (2.22 GBq) at end-of-synthesis (EOS)), at high specific activity (molar activity > 11,435 mCi/μmole (423 GBq/μmole) at EOS)

We report an efficient protocol for the radiosynthesis of diastereomerically pure (E)-[11 C]ABP688, a positron emission tomography (PET) tracer for metabotropic glutamate type 5 (mGlu5) receptor imaging. The protocol reliably provides sterile and pyrogen-free formulation of (E)-[11 C]ABP688 suitable for preclinical and clinical PET imaging with >99% diastereomeric excess (d.e.), >99% overall radiochemical

The aim is to introduce and characterize a new experimental demonstrative model contributing to the increase of measurement accuracy, in terms of minimum detectable activity (MDA) and background reduction, for the analysis of samples having low concentrations in tritium and radiocarbon on Quantulus 1220. The clue is related to the qualitative and quantitative differences between tritium and carbon-14

Transition-metal mediated carbonylation with 11 C-labelled carbon monoxide ([11 C]CO) is a versatile method for introducing 11 C (t1/2 = 20.3 min) into drugs and radioligands for subsequent use in positron emission tomography (PET). The aim of the current study was to perform the 11 C-carbonylation reaction on the interior surface of a stainless-steel loop used for high performance liquid chromatography

Rituximab is used for the treatment of non-Hodgkin lymphoma (NHL). This study focuses on development of 68 Ga-labeled rituximab fragments, (68 Ga-NOTA-F (ab')-rituximab and 68 Ga-NOTA-F (ab')2 -rituximab, as PET-imaging agents for NHL. Rituximab was digested with immobilized pepsin and papain to yield F (ab')2 and Fab fragments respectively that were characterized by size exclusion HPLC (SE-HPLC) and

A deeper understanding of the pharmacokinetic and pharmacodynamic properties of a drug candidate is a pivotal component of drug discovery and development. Autoradiography is an excellent technique allowing exploiting the advantages of the use of radioisotopes in the drug disscovery field. The introduction of phosphor imaging technology has revolutionized the handling of drug distribution studies providing

18 O-labeled water (Water-18 O) is a widely used starting material of 18 F-labeled diagnostic agents in positron emission tomography (PET). Conventionally, Water-18 O has been separated from other stable oxygen isotope species (16 O, 17 O) by water distillation or nitric oxide distillation. However, conventional methods are costly and may have safety issues. In 2004, we developed the first unit of

This study aims at analyzing complexation properties of two new short somatostatin analogues, their synthesis, radiolabeling with 44 Sc, 207 Bi, and 152 Eu and stability in vitro. Short tetrapeptide Phe-d-Trp-Lys-Thr and pentapeptide Thz-Phe-d-Trp-Lys-Thr were first conjugated with the DOTA macrocyclic chelator. These conjugates were radiolabeled with 44 Sc, 207 Bi, and 152 Eu and characterized by

Experimental results of the second series of experiments on the penetration of monodisperse polymeric particles, inhaled at low dose by mice, to different organs using direct way of particle registration, based on the ultra-sensitive accelerator mass spectrometer (AMS), are presented. Polystyrene (PS) beads, composed of radiocarbon-labeled styrene, were produced for testing them as model organic aerosols

Research over the past 25 years and the use of accelerator mass spectrometry (AMS) have demonstrated benefits of single-atom counting of 14 C compared with scintillation monitoring of 14 C radioactive decay for a multitude of applications in drug development studies. These include pharmacokinetics and metabolism studies, microdosing studies, and quantification of DNA adducts. In the last decade, the

Radiolabeled Arg-Gly-Asp (RGD) peptide derivatives have immense potential for non-invasive monitoring of malignancies overexpressing integrin αv β3 receptors. Easy availability of suitable radiotracers would augment the utility of this class of molecular imaging agents. Towards this, the present article describes the development of an improved lyophilized kit for the routine clinical formulation of

The acyclic chelator HBED-CC has attained huge clinical significance owing to high thermodynamic and kinetic stability of 68 Ga-HBED-CC chelate. It provides an excellent platform for quick preparation of 68 Ga-based radiotracers in high yield. Thus, the present study aimed at conjugation of gastrin releasing peptide receptor (GRPr) antagonist, RM26, with HBED-CC chelator for 68 Ga-labeling. In vitro

The number of therapeutic antibodies in research and development as well as their complexity increases from year to year. Novel therapeutic protein formats, such as Fc-fusions, bispecific, or multivalent antibodies, are currently in preclinical and clinical development. Therefore, the need for biodistribution and imaging studies, eg, with radiolabeled proteins are very high. However, the labeling process

Fluorine-18 labeled hydroxyphenethylguanidines were recently developed in our laboratory as a new class of PET radiopharmaceuticals for quantifying regional cardiac sympathetic nerve density in heart disease patients. Studies of 4-[18 F]fluoro-m-hydroxyphenethylguanidine ([18 F]4F-MHPG) and 3-[18 F]fluoro-p-hydroxyphenethylguanidine ([18 F]3F-PHPG) in human subjects have shown that these radiotracers

Targeted alpha therapy (TAT) is a promising approach for the treatment of cancer. The use of alpha emitters for cancer therapy has two distinct advantages over conventional therapies. The short range of alpha radiation in human tissue (less than 0.1 mm), corresponding to only a few cell diameters, allows selective killing of targeted cancer cells while sparing surrounding healthy tissue. At the same

An integrated methodological approach to study the molecular aspects of short regulatory neuropeptides biological mechanism is proposed. The complex research is based on radioligand-receptor method of analysis and covers such points of peptides molecular activity as: specific binding of peptides to brain cells plasmatic membranes, formation of tissue specific synacton, influence of peptides (as allosteric