Cellular uptake and photo-cytotoxicity of a gadolinium(III)-DOTA-naphthalimide complex "clicked" to a lipidated tat peptide

William O'Malley, Riccardo Rubbiani, Maggie Aulsebrook, Michael Grace, Leone Spiccia, Kellie Tuck, Gilles Gasser, Bimbil Graham

Research output: Contribution to journalArticleResearchpeer-review

10 Citations (Scopus)


A new bifunctional macrocyclic chelator featuring a conjugatable alkynyl-naphthalimide fluorophore pendant group has been prepared and its Gd(III) complex coupled to a cell-penetrating lipidated azido-Tat peptide derivative using Cu(I)-catalysed "click" chemistry. The resulting fluorescent conjugate is able to enter CAL-33 tongue squamous carcinoma cells, as revealed by confocal microscopy, producing a very modest anti-proliferative effect (IC50 = 93 μM). Due to the photo-reactivity of the naphthalimide moiety, however, the conjugate's cytotoxicity is significantly enhanced (IC50 = 16 μM) upon brief low-power UV - A irradiation.

Original languageEnglish
Article number194
Pages (from-to)1-16
Number of pages16
Issue number2
Publication statusPublished - 1 Feb 2016


  • Cell-penetrating peptide
  • Fluorescence
  • Gadolinium complex
  • Photo-cytotoxicity
  • Theranostic

Cite this