Abstract/Video opens by clicking at the talk title.
Vectormolecules for radionuclide imaging and chemistry of carbon-11, fluorine-18 and radioiodine (#693)
1 KU Leuven, Radiopharmaceutical Research, Leuven, Belgium
-general characteristics of the molecular structure of probes for radionuclide imaging comprising the vector-linker-radionuclide principle
Radionuclide imaging provides quantification of the radionuclide concentration as a function of time after administration.
Keywords: radionuclide imaging, vector, carbon-11, fluroine-18, radio-iodine
Chemistry of Radiometals (#716)
1 University of Missouri, Chemistry, Columbia, United States of America
•To present an overview on radiometal-based PET and SPECT tracers and how chelation chemistry is important
Radiometals are very important in the fields of radiopharmaceutical chemistry and nuclear medicine, and they span the periodic table ranging from Sc-44 to Ac-225. This presentation will focus on selected radiometals that are used clinically or are established in pre-clinical and/or human studies (Ga-68, Cu-64, Zr-89 for PET imaging; Tc-99m, In-111, and Lu-177 for SPECT imaging). The chemistry of radiometals requires an understanding of coordination chemistry and how to design chelators for stable complexation in vivo. Radiolabeling chemistry considerations include minimizing trace metal contamination and choosing the best buffer systems and pH. Choosing chelators will depend on several factors such as the hard/soft characteristic of the metal, the preferred oxidation state, and the lability of the radiometal towards dissociation to protein binding in vivo. The preferred coordination environment for radiometals will greatly affect the biodistribution of a chelator-peptide conjugate. Cell surface receptors and enzyme inhibitors are often upregulated on tumors and are a common target for designing radiotracers for imaging and therapy. Radiometal-based agents targeting somatostatin receptor and prostate specific membrane antigen (PSMA) will be described, including different chelator choices made based on optimizing target uptake with fast non-target organ clearance. The chelation chemistry of Zr(IV) will also be included and a novel chelator system under investigation will be described for immunoPET and radioimmunotherapy.
Keywords: radiometal, cell surface receptor, immunoPET
Chemistry of Optical Probes: Fluorophores and Sonophores (#712)
1 RWTH Aachen University, Experimental Molecular Imaging, Aachen, Germany
This Education Talk will highlight some of recent progresses in the small molecule organic fluorophores, innovative design strategies and fine-tuning of optical properties. In particular, an emphasis is placed on trigger-responsive probes, detecting enzyme activity or cellular metabolites. Viewers will learn about variety of possibilites in the development of optical probes suitable for required applications.
Light-based imaging modalities are of high importance in the field of medical imaging, in particular those based on fluorescence and photoacoustic, as they enable very sensitive and fast imaging at high resolution. For fluorescence imaging, probes emitting a large number of photons per excitation event are most suitable, while for photoacoustic non-emitting compounds are preferred; nevertheless, in both cases chromophores exhibiting absorption / emission in tissue-transparent window (near infrared, NIR) are needed. Therefore, this talk highlights few recent developments towards such NIR-probes.
1) J. Am. Chem. Soc. 2019, 141, 2770
AcknowledgmentFinancial support from I3TM Seed Fund, START grant from RWTH Aachen University
1. Zwicker, VE, Oliveira, BL, Yeo JH, Fraser, ST, Bernardes, GJL, New EJ, Jolliffe KA, 2019, 'A Fluorogenic Probe for Cell Surface Phosphatidylserine Using an Intramolecular Indicator Displacement Sensing Mechanism' Angew. Chem. Int. Ed. Engl., 58, 3087.
2. Kawatani, M, Yamamoto, K, Yamada, D, Kamiya, M, Miyakawa, J, Miyama Y, Kojima, R, Morikawa, T, ,H, Urano, Y, 2019, 'Fluorescence Detection of Prostate Cancer by an Activatable Fluorescence Probe for PSMA Carboxypeptidase Activity' J. Am. Chem. Soc., 141, 10409.
3. B. Ding, Y. Xiao, H. Zhou, X. Zhang, C. Qu, F. Xu, Z. Deng, Z. Cheng and X. Hong, 2019, 'Polymethine Thiopyrylium Fluorophores with Absorption beyond 1000 nm for Biological Imaging in the Second Near-Infrared Subwindow', J. Med. Chem. 62, 2049.
4. F. Liu, X. Shi, X. Liu, F. Wang, H.-B. Yi and J.-H. Jiang, 2019, 'Engineering an NIR rhodol derivative with spirocyclic ring-opening activation for high-contrast photoacoustic imaging', Chem. Sci., 10, 9257
5. E. Y. Zhou, H. J. Knox, C. Liu, W. Zhao and J. Chan, 2019, 'A Conformationally Restricted Aza-BODIPY Platform for Stimulus-Responsive Probes with Enhanced Photoacoustic Properties', J. Am. Chem. Soc.141, 17601.
Keywords: Trigger-responsive, fine-tuning, core-modifications
The chemistry of Magnetic Resonance Imaging probes: basic concepts (#642)
1 University of Eastern Piedmont "A. Avogadro", DISIT, Alessandria, Italy
After completion of this lecture, participants are aware of:
A. Merbach, L. Helm, É. Tóth (Eds) “The Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging, Second Edition”, 2013, John Wiley & Sons, Ltd
S. Aime, M. Botta, E. Terreno. Gd(III)-based contrast agents for MRI. Adv Inorg Chem 2005; 57: 173–237
P. Caravan, J.J. Ellison, T.J. McMurry, R.B. Lauffer. Gadolinium(III) Chelates as MRI contrast agents: structure, dynamics, and applications. Chem Rev 1999; 99: 2293–2352
AcknowledgmentThe author gratefully acknowedges Prof. Silvio Aime, Prof. Enzo Terreno, Prof. Mauro Botta and Prof. Daniela Delli Castelli for helpful discussions and for sharing their educational material.
Keywords: MRI, gadolinium, relaxivity, contrast agent