Radiopharmaceutical Chelators

How this supports a project

This platform is limited to cold, non-radioactive chelators, bifunctional derivatives, targeting-ligand intermediates, and precursor building blocks. Chelator selection must start with the intended metal, coordination requirements, labeling conditions, and carrier-conjugation route.

Match the chelator to the metal and workflow

DOTA, NOTA, DFO, DTPA, and related structures differ in donor set, denticity, geometry, ring or chain architecture, complexation kinetics, and practical labeling conditions. They are not interchangeable. Metal oxidation state, coordination preference, required stability, temperature, pH, time, and carrier tolerance must be considered together.

A bifunctional chelator also requires a separately usable group for attachment to a peptide, antibody, small-molecule ligand, or other vector. Handle identity, attachment position, spacer, chelator loading, and conjugation route can alter the cold conjugate and later radiochemistry.

Typical cold-precursor workflow

Define radionuclide or metal

Record intended radionuclide, metal oxidation state, application, labeling window, and any non-radioactive analogue needed for development.

Define the targeting vector

Provide exact peptide, antibody, small molecule, or other vector, its attachment site, and binding-critical groups.

Select chelator family

Match donor atoms, denticity, architecture, kinetics, stability needs, and labeling conditions to the metal.

Select bifunctional handle and spacer

Match NHS, NCS, maleimide, click, or another handle to the vector and define spacer and conjugation order.

Prepare and characterize cold material

Confirm structure, identity, purity, metal-binding groups, conjugation site, residual metals or reagents, water content, and storage.

Transfer to qualified radiochemistry

A licensed team must establish radiolabeling yield, radiochemical purity, molar activity, stability, binding, biodistribution, dosimetry, and intended-use suitability.

Inputs for platform review

Metal and use case

Radionuclide or cold analogue, imaging or therapy objective, decay or preparation constraints, and expected workflow.

Labeling conditions

Acceptable pH, temperature, time, buffer, precursor concentration, and vector sensitivity.

Targeting vector

Exact identity or structure, attachment position, critical groups, available reactive groups, amount, and formulation.

Chelator format

Chelator family, bifunctional handle, spacer, protection state, conjugation sequence, and required cold metal complex if any.

Analytical specification

Identity, purity, residual metals, free chelator, chelator-to-vector ratio, aggregation where relevant, water, salt form, and storage stability.

Where this platform applies

All materials described here are cold and non-radioactive. CHEMOS does not provide radionuclides, radioactive materials, radiolabeling, radioactive transport, dose preparation, clinical manufacture, imaging or therapeutic performance, dosimetry, safety, or regulatory approval. Final chelator choice and radiochemistry remain the responsibility of the qualified project team.

Core considerations

DOTA, NOTA, DFO, DTPA, and related chelators
NHS, NCS, maleimide, and click-enabled chelator handles
PSMA, FAPI, and vector-conjugation precursor planning

Related catalog and technical pages

Radiopharmaceutical chelators and precursorsBrowse cold chelators, bifunctional derivatives, targeting-ligand intermediates, and non-radioactive precursors.Radiopharmaceutical precursor planningReview the complete workflow from intended metal and targeting vector to cold precursor and external radiochemistry.Conjugation chemistry and linkersReview attachment handles, spacers, reaction order, purification, and carrier-conjugate analysis.DOTA, NOTA, and DFO comparisonReview why chelator choice depends on metal, labeling conditions, vector, and stability needs.Click chemistry and bioconjugation reagentsBrowse click, NHS ester, maleimide, and related handles used in bifunctional chelator assembly.