Small molecule imaging catalysis

Only few methods exists today for F-labeling of peptides (typically acylation and reductive amination) so Arstad and Glaser developed methods for radiolabeling peptides and small molecules with fluorine-18. ° A radiolabeled azide was reacted with an alkyne-derivatized peptide, nsing copper(I) catalysis, to afford a F-triazole-linked peptide 95 useful for in vivo imaging (see Scheme 10.27). 

For more than two decades, extensive research work has been devoted to the unique properties of clusters. They are made of a small number (or nucleaiity) of atoms or molecules only, and therefore constitute a new state of matter, or mesoscopic phase, between the atom or molecule and the crystal. New methods have been developed in physics and chemistry for their synthesis, their direct observation, the study of their properties, and of their crucial role in number of processes, such as phase transition, catalysis, surface phenomena, imaging. Owii to its specific approach, radiation chemistry offei first the opportunity to reveal the existence of nuclearity-dependent properties of clusters and has then proven to be a powerfid method to study the mechanisms of cluster formation and reactivity in solution. 

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