¹⁵³Sm-Radiolabeling Service

¹⁵³Sm-radiolabeling services provide a robust platform for the development of targeted radiopharmaceuticals, which use the therapeutic and diagnostic features of Samarium-153 for SPECT imaging and bone pain palliation. Alfa Cytology has a wide range of knowledge and modern facilities to offer quality and tailored ¹⁵³Sm radiolabeling to the clients for their preclinical investigation and pharmaceutical development.

Introduction to ¹⁵³Sm Isotopes

Samariam-153 (¹⁵³Sm) has become an indispensable radionuclide due to its unique decay characteristics. Its decay emits both beta medium-energy particles, which can be used for therapeutic purposes, as well as a gamma photon (103.2 keV), which can be used for concurrent scintigraphy imaging. The physical half-life of 46.3 hours is ideal for the production of radiopharmaceuticals as well as the individual's administration. This makes it a prime candidate for the development of radioisotopes used in targeted radionuclide therapy, which is used most commonly for the palliation of painful bone metastases.

¹⁵³Sm-Labeling for SPECT Imaging

SPECT imaging can utilize ¹⁵³Sm-labeling due to the gamma photons emitted by the radionuclide at 103.2 keV, a level that a gamma camera can detect. It can therefore directly view the biodistribution of the labeled agent and pharmacokinetically track it in real time. The imaging capability is important for dosimetry calculations and for therapeutically assessing the targeting of ¹⁵³Sm to pathological locations (like bone metastases), although ¹⁵³Sm is primarily noted for its therapeutic beta emission. In radiology, this distinguishing property makes ¹⁵³Sm-labeled compounds particularly potent theranostic agents.

Fig.1 Schematic scheme of labeling procedure of Dextran-coated iron oxide NPs with an amine group conjugated with ccDTPA and labeled with ¹⁵³Sm finally. (GHOLAMI A, et al., 2016)

¹⁵³Sm Radiopharmaceutical

Disclaimer: Alfa Cytology focuses on providing preclinical research services. This table is for information exchange purposes only. This table is not a treatment plan recommendation. For guidance on treatment options, please visit a regular hospital.

Our Services

With in-depth expertise and experience in radiochemistry, Alfa Cytology offers fully comprehensive ¹⁵³Sm-labeling services aimed at advancing the novel radiopharmaceuticals from initial conjugation to preclinical evaluation. With the aid of our latest facilities, along with our experienced scientists, we guarantee the provision of custom radiolabeled agents able to satisfy the rigid requirements of your therapeutic and diagnostic studies.

Custom ¹⁵³Sm Conjugation Service

From peptides and antibodies to small molecules and nanoparticles, our service expertly conjugates Samarium-153 to a diverse array of targeting vectors for next-generation radiopharmaceutical development.

Small-Molecule Radionuclide Conjugate (SMRC)

Antibody-Radionuclide Conjugate (ARC)

Peptide-Radionuclide Conjugate (PRC)

siRNA-Radionuclide Conjugate

Workflow for Developing ¹⁵³Sm-Radiolabeled Peptide Conjugates

¹⁵³Sm Custom Antibody Labeling

• Strategy & Reagent Selection: Starting the project by defining the labeling strategy (direct vs. bifunctional chelator-mediated methods) and determining the best chelator/peptide conjugates (e.g., DOTA, DTPA) and their reaction conditions for high specific activity and excellent radiochemical yield.
• Ligand Conjugation: Carrying out the chemical reaction to covalently attach the selected bifunctional chelator to the monoclonal antibody or the peptide. This is an essential step for preparing the precursor ready to bind the radioisotope. At this step, the chelator-to-protein ratio is optimized for best performance.
• Protocol Optimization: Carefully examines and adjusts fundamental parameters in radiolabeling, such as temperature, pH, time, and ligand-to-metal ratios. Establishes a particular procedure that achieves the best radiochemical yield without compromising the biomolecule.
• Custom Radiosynthesis: Implements the final, optimized radiolabeling reaction by incubating the conjugated precursor with ¹⁵³Sm under controlled conditions. Reproducibly performs the crude ¹⁵³Sm-labeled conjugate for immediate subsequent purification.

Purification & Quality Control

Following labeling, to verify the incorporation of ¹⁵³Sm. Correct isotopic labeling, purity, and stability of the isotopic compound, together with meeting the necessary standards for biological studies, are assessed by liquid chromatography (LC), mass spectrometry (MS), and scintillation counting.

In Vitro Evaluation

In vitro tests are performed to evaluate the biological properties of the ¹⁵³Sm-labeled radiopharmaceutical. This includes studying its interaction with target receptors, cellular uptake, metabolic stability, and other pharmacological properties.

In Vivo Evaluation

Initially, this crucial stage involves the quantitative biodistribution of the agent and various pharmacokinetic (PK) studies to assess organ uptake and the agent's clearance from the body. After that, SPECT imaging is done subsequently in the relevant disease models to visually assess specific target engagement and to unambiguously confirm the agent's diagnostic potential by in vivo diagnostic blocking experiments.

Applications of ¹⁵³Sm-Radiolabeling

Harnessing its unique theranostic properties, ¹⁵³Sm-radiolabeling is advancing a new generation of targeted agents across a spectrum of preclinical applications.

Radiopharmaceutical Development &
Preclinical Research

• In Vivo Pharmacokinetic and ADME Studies
• Dosimetry Assessment
• Development of Theranostic Agents
• Receptor Targeting and Binding Assays
• More

Targeted Radionuclide Therapy (TRT)

• Palliative Treatment of Bone Metastases
• Radiosynovectomy for Arthritis Treatment
• Myeloablative Conditioning for Stem Cell Transplantation
• Treatment of Primary Bone Sarcomas
• More

Having extensive experience in radionuclide chemistry, Alpha Cytology provides custom ¹⁵³Sm-radiolabeling services as a support to the development of complex radiopharmaceuticals. To learn more about how our team of specialists, in conjunction with our advanced infrastructure, can assist in the advancement of your next project, please contact us for a detailed consultation.

Reference

1. GHOLAMI A, MOUSAVIE ANIJDAN S H. Development of (¹⁵³)Sm-DTPA-SPION as a theranostic dual contrast agents in SPECT/MRI [J]. Iranian journal of basic medical sciences, 2016, 19(10): 1056-62.

For research use only. Not intended for any clinical use.