Multi-Functionalized Carbon Nano-onions as Imaging Probes for Cancer Cells.

Carbon-based nanomaterials have attracted much interest during the last decade for biomedical applications. Multimodal imaging probes based on carbon nano-onions (CNOs) have emerged as a platform for bioimaging because of their cell-penetration properties and minimal systemic toxicity. Here, we describe the covalent functionalization of CNOs with fluorescein and folic acid moieties for both imaging and targeting cancer cells.

Native chemical ligation,thiol-ene click: a methodology for the synthesis of functionalized peptides.

The sequential combination of native chemical ligation and thiol-ene radical chemistry (NCL-TEC) on the resulting cysteine thiol has been investigated as a methodology for rapidly accessing functionalized peptides. Three sequential cycles of native chemical ligation and subsequent thiyl radical reactions (including a free-radical-mediated desulfurization reaction) were carried out on a peptide backbone demonstrating the iterative nature of this process. The versatility of the thiyl radical reaction at cysteine was demonstrated through the introduction of a number of different side chains including an amino acid derivative, a carbohydrate group, and an alkyl azide.