Enhancing Magnetic Hyperthermia Efficiency in Pd/Fe-Oxide Hybrid Nanoparticles through Mn-Doping.

Multifunctional, biocompatible magnetic materials, such as iron oxide nanoparticles (IONPs), hold great potential for biomedical applications including diagnostics (e.g., MRI) and cancer therapy.

Lead-212/Bismuth-212 In Vivo Generator Based on Ultrasmall Silver Telluride Nanoparticles.

Radionuclide therapy employing alpha emitters holds great potential for personalized cancer treatment. However, certain challenges remain when designing alpha radiopharmaceuticals, including the lack of stability of used radioconjugates due to nuclear decay events. In this work, ultrasmall silver telluride nanoparticles with a core diameter of 2.

Ultrasmall Gold Nanoparticles Radiolabeled with Iodine-125 as Potential New Radiopharmaceutical.

The relatively high linear energy transfer of Auger electrons, which can cause clustered DNA damage and hence efficient cell death, makes Auger emitters excellent candidates for attacking metastasized tumors. Moreover, gammas or positrons are usually emitted along with the Auger electrons, providing the possibility of theragnostic applications. Despite the promising properties of Auger electrons, only a few radiopharmaceuticals employing Auger emitters have been developed so far.

Magnetic hybrid Pd/Fe-oxide nanoparticles meet the demands for ablative thermo-brachytherapy.

Objective: To investigate the potential of hybrid Pd/Fe-oxide magnetic nanoparticles designed for thermo-brachytherapy of breast cancer, considering their specific loss power () and clinical constraints in the applied magnetic field.

Methods: Hybrid nanoparticles consisting of palladium-core and iron oxide shell of increasing thickness, were suspended in water and their were measured at varying magnetic fields (12-26 mT peak) and frequencies (50-730 kHz) with a commercial alternating magnetic field generator (magneTherm™ Digital, nanoTherics Ltd.).

First preclinical evaluation of [Ac]Ac-DOTA-JR11 and comparison with [Lu]Lu-DOTA-JR11, alpha versus beta radionuclide therapy of NETs.

Background: The [Lu]Lu-DOTA-TATE mediated peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NETs) is sometimes leading to treatment resistance and disease recurrence. An interesting alternative could be the somatostatin antagonist, [Lu]Lu-DOTA-JR11, that demonstrated better biodistribution profile and higher tumor uptake than [Lu]Lu-DOTA-TATE. Furthermore, treatment with alpha emitters showed improvement of the therapeutic index of PRRT due to the high LET offered by the alpha particles compared to beta emitters.

Design and Validation of Experimental Setup for Cell Spheroid Radiofrequency-Induced Heating.

While hyperthermia has been shown to induce a variety of cytotoxic and sensitizing effects on cancer tissues, the thermal dose-effect relationship is still not well quantified, and it is still unclear how it can be optimally combined with other treatment modalities. Additionally, it is speculated that different methods of applying hyperthermia, such as water bath heating or electromagnetic energy, may have an effect on the resulting biological mechanisms involved in cell death or in sensitizing tumor cells to other oncological treatments. In order to further quantify and characterize hyperthermia treatments on a cellular level, in vitro experiments shifted towards the use of 3D cell spheroids.

Membrane-based microfluidic solvent extraction of Ga-68 from aqueous Zn solutions: towards an automated cyclotron production loop.

Background: The radionuclide Ga-68 is commonly used in nuclear medicine, specifically in positron emission tomography (PET). Recently, the interest in producing Ga-68 by cyclotron irradiation of [Zn]Zn nitrate liquid targets is increasing. However, current purification methods of Ga-68 from the target solution consist of multi-step procedures, thus, leading to a significant loss of activity through natural decay.

From Structure to Function: Understanding Synthetic Conditions in Relation to Magnetic Properties of Hybrid Pd/Fe-Oxide Nanoparticles.

Heterostructured magnetic nanoparticles show great potential for numerous applications in biomedicine due to their ability to express multiple functionalities in a single structure. Magnetic properties are generally determined by the morphological characteristics of nanoparticles, such as the size/shape, and composition of the nanocrystals. These in turn are highly dependent on the synthetic conditions applied.

Highlight selection of radiochemistry and radiopharmacy developments by editorial board.

Background: The Editorial Board of EJNMMI Radiopharmacy and Chemistry releases a biannual highlight commentary to update the readership on trends in the field of radiopharmaceutical development.

Main Body: This commentary of highlights has resulted in 21 different topics selected by each coauthoring Editorial Board member addressing a variety of aspects ranging from novel radiochemistry to first in man application of novel radiopharmaceuticals.

Conclusion: Trends in radiochemistry and radiopharmacy are highlighted demonstrating the progress in the research field in various topics including new PET-labelling methods, FAPI-tracers and imaging, and radionuclide therapy being the scope of EJNMMI Radiopharmacy and Chemistry.

Core-shell structured gold nanoparticles as carrier for Dy/Ho in vivo generator.

Background: Radionuclide therapy (RNT) has become a very important treatment modality for cancer nowadays. Comparing with other cancer treatment options, sufficient efficacy could be achieved in RNT with lower toxicity. β emitters are frequently used in RNT due to the long tissue penetration depth of the β particles.

Effects of High Gamma Doses on the Structural Stability of Metal-Organic Frameworks.

Four different MOFs were exposed to γ rays by a cobalt-60 source reaching a maximum dose of 5 MGy. The results showed that the MIL-100 (Cr) and MIL-100 (Fe) did not exhibit obvious structural damage, suggesting their excellent radiation stability. MIL-101 (Cr) showed good radiation stability up to 4 MGy, but its structure started degrading with increasing radiation dose.

Thioanisole ester based logic gate cascade to control ROS-triggered micellar degradation.

In certain tumor and diseased tissues, reactive oxygen species (ROS), such as HO, are produced in higher concentrations than in healthy cells. Drug delivery and release systems that respond selectively to the presence of ROS, while maintaining their stability in "healthy" biological conditions, have great potential as on-site therapeutics. This study presents polymer micelles with 4-(methylthio)phenyl ester functionalities as a ROS-responsive reactivity switch.

Light-Sensitive Phenacyl Crosslinked Dextran Hydrogels for Controlled Delivery.

Stimuli-responsive soft materials enable controlled release of loaded drug molecules and biomolecules. Controlled release of potent chemotherapeutic or immunotherapeutic agents is crucial to reduce unwanted side effects. In an effort to develop controlled release strategies that can be triggered by using Cerenkov luminescence, we have developed polymer hydrogels that can release bovine serum albumin and immunoglobulin G by using light (254 nm-375 nm) as a trigger.

Highlight selection of radiochemistry and radiopharmacy developments by editorial board.

Background: The Editorial Board of EJNMMI Radiopharmacy and Chemistry releases a biyearly highlight commentary to update the readership on trends in the field of radiopharmaceutical development.

Results: This commentary of highlights has resulted in 21 different topics selected by each member of the Editorial Board addressing a variety of aspects ranging from novel radiochemistry to first in man application of novel radiopharmaceuticals. Also the first contribution in relation to MRI-agents is included.

Photo cleavable thioacetal block copolymers for controlled release.

We present a new light cleavable polymer containing -nitrobenzene thioacetal groups in the main chain. By conjugation to a PEG block, we synthesized block copolymers capable of forming nanoparticles in aqueous solution. We studied drug encapsulation and release using the model drug Nile Red.

Nuclear Waste and Biocatalysis: A Sustainable Liaison?

It is well-known that energy-rich radiation induces water splitting, eventually yielding hydrogen peroxide. Synthetic applications, however, are scarce and to the best of our knowledge, the combination of radioactivity with enzyme-catalysis has not been considered yet. Peroxygenases utilize HO as an oxidant to promote highly selective oxyfunctionalization reactions but are also irreversibly inactivated in the presence of too high HO concentrations.

Modelling of the Lu/Lu radionuclide generator.

In order to determine the potential of Lu/Lu radionuclide generator in Lu production it is important to establish the technical needs that can lead to a clinically acceptable Lu product quality. In this work, a model that includes all the processes and the parameters affecting the performance of the Lu/Lu radionuclide generator has been developed. The model has been based on the use of a ligand to complex Lu ions, followed by the separation of the freed Lu ions.

The application of atomic layer deposition in the production of sorbents for Mo/Tc generator.

New production routes for Mo are steadily gaining importance. However, the obtained specific activity is much lower than currently produced by the fission of U-235. To be able to supply hospitals with Mo/Tc generators with the desired activity, the adsorption capacity of the column material should be increased.

Solid phase extraction-based separation of the nuclear isomers Lu and Lu.

A solid phase extraction based Lu-Lu separation method has been investigated for its feasibility to be used in the radionuclide generator. The use of 2,2',2"-(10-(2,6-dioxotetrahydro-2H-pyran-3-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid, (DOTAGA-anhydride) allowed grafting of DOTA (1,4,7,10-tetraazacyclododecane N,N',N″,N‴-tetraacetic acid) complex on the surface of commercially available amino propyl silica. The grafting of DOTA has been confirmed by several characterization techniques.

Cu enrichment using the Szilard-Chalmers effect - The influence of γ-dose.

Cu is an important trace metal which plays a role in many biological processes. The radioisotope Cu is often used to study such processes. Furthermore, Cu finds applications in cancer diagnostics as well as therapy.

Uptake and subcellular distribution of radiolabeled polymersomes for radiotherapy.

Polymersomes have the potential to be applied in targeted alpha radionuclide therapy, while in addition preventing release of recoiling daughter isotopes. In this study, we investigated the cellular uptake, post uptake processing and intracellular localization of polymersomes. High-content microscopy was used to validate polymersome uptake kinetics.

Preclinical evaluation of binimetinib (MEK162) delivered via polymeric nanocarriers in combination with radiation and temozolomide in glioma.

Background And Purpose: Glioblastoma multiforme (GBM) is the most aggressive subtype of malignant gliomas, with an average survival rate of 15 months after diagnosis. More than 90% of all GBMs have activating mutations in the MAPK/ERK pathway. Recently, we showed the allosteric MEK1/2 inhibitor binimetinib (MEK162) to inhibit cell proliferation and to enhance the effect of radiation in preclinical human GBM models.

Large-scale production of lutetium-177m for the Lu/Lu radionuclide generator.

In this work, Lu has been produced by irradiation of natural LuO targets at the BR2 reactor (Mol, Belgium) and the obtained data together with literature values have been used to theoretically investigate the production of Lu at different neutron fluxes, irradiation times and enrichment of Lu. The irradiation time (t) needed to reach the maximum Lu production has been found to change from 42, 12, 4 days with the increase in the thermal neutron flux from 2*10, 8*10, 2.5*10 n cm s, respectively while keeping the maximum Lu activity unaffected.

Preparation and characterization of inorganic radioactive holmium-166 microspheres for internal radionuclide therapy.

Microspheres with high specific activities of radionuclides are very interesting for internal radiotherapy treatments. This work focuses on the formulation and characterization of inorganic microspheres with a high content of holmium and therefore a high specific radioactivity of holmium-166. Two novel formulations of inorganic microspheres were obtained by dispersing solid holmium acetylacetonate microspheres (Ho(AcAc)-ms) in NaHPO or NaOH solutions followed by 2 h incubation at room temperature.