Organometallic Gold(III) Complexes for Radiolabeling Biomolecules for Applications in Positron Emission Tomography (PET) Molecular Imaging (UCLA Case No. 2022-282)

UCLA researchers led by Professor Jennifer Murphy in the Department of Molecular and Medical Pharmacology have developed a novel platform that leverages organometallic gold(III) complexes for next-generation radiolabeling of biomolecules in PET molecular imaging. This technology is strategically positioned to meet the rapidly expanding demands of precision diagnostics and targeted therapeutics in oncology, neurology, and cardiology.

BACKGROUND: Traditional radiolabeling methods often struggle with limited stability, complex synthesis, and lower biocompatibility. Gold(III) complexes offer enhanced chemical stability and predictable ligand exchange, allowing rapid and specific conjugation with a variety of targeting biomolecules such as antibodies, peptides, and small molecules.

ADVANTAGES:

• High Stability: Gold(III) organometallic complexes resist degradation in physiological environments, leading to more robust tracers that minimize off-target breakdown and background signal, thus improving image contrast and diagnostic accuracy.
• Versatility: The technology enables radiolabeling of various biomolecules—including those that previously lacked compatible labeling strategies—opening PET imaging possibilities for a wide array of targets and disease indications.
• Efficiency: The rapid and mild conjugation chemistry preserves biomolecule integrity, reducing manufacturing complexity and cost, and allowing for the labeling of fragile proteins or peptides.
• Safety: By minimizing free radioisotope release and off-target reactions, these complexes contribute to safer imaging agent profiles for clinical use.

APPLICATIONS:

• Precision PET Imaging: Gold(III)-based radiolabeled tracers can improve detection, staging, and monitoring of cancer, cardiovascular, and neurological diseases by precisely tracking specific disease-associated biomolecules in vivo.
• Theranostics: Gold(III) complexes can be adapted for dual imaging and therapeutic applications, supporting the development of next-generation theranostic agents.
• Biomarker Discovery: The platform facilitates rapid screening and validation of new biomarkers for molecular imaging and personalized medicine.

CONCLUSION: This technology delivers an innovative approach to PET tracer development through organometallic gold(III) chemistry, yielding more stable, specific, and versatile radiolabeling agents for advanced molecular imaging.

KEYWORDS: molecular imaging, radiotracer development, PET imaging, radiolabeling chemistry, biomarker targeting