title: Synthesis, penetrability and intracellular targeting of fluorescein-tagged peptoids and peptide-peptoid hybrids.
abstract: The search for novel, generally applicable and highly efficient delivery tools is a major activity in the biotechnology arena. Using highly optimized microwave based solid-phase chemistry a series of fluorescein-labelled cationic peptoid conjugates were synthesized within 24h and cellular uptake into HeLa, L929 and K562 cells examined via flow cytometry. As expected, analysis revealed that longer oligomers achieved greater cellular penetration (7e (9 mer)>7d (7 mer)>7c (5 mer)>7b (3 mer)>7a (1 mer)) with the nonamer 7e proving to be a remarkable vehicle for all the cell lines, showing excellent penetrability into K562 and L929 cells and extraordinary cell delivery into HeLa cells. Confocal microscopy showed that the hybrid peptoid-nuclear localizing sequence (PKKKRKV from the simian virus 40 large T antigen) resulted in very high levels of nuclei delivery after 3h, opening up a range of applications such as nuclei staining of living cells with non-DNA-intercalating fluorescent probes.
authors.affiliation: School of Chemistry, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh EH9 3JJ, UK.
authors.forename: Asier
authors.initials: A
authors.lastname: Unciti-Broceta
authors.forename: Franziska
authors.initials: F
authors.lastname: Diezmann
authors.forename: Chiung Ying
authors.initials: CY
authors.lastname: Ou-Yang
authors.forename: Mario Antonio
authors.initials: MA
authors.lastname: Fara
authors.forename: Mark
authors.initials: M
authors.lastname: Bradley
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport; D045744:Cell Line, Tumor; D002463:Cell Membrane Permeability; D002467:Cell Nucleus / Q000737:chemistry; D005434:Flow Cytometry; D019793:Fluorescein / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D034444:Peptoids / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D010455:Peptides; D034444:Peptoids; D019793:Fluorescein