One-pot peptide cyclisation and surface modification of photosensitiser-loaded red blood cells for targeted photodynamic therapy.

We report herein a one-pot approach to cyclise a tumour-targeting peptide and conjugate it on the surface of red blood cells loaded with a boron dipyrromethene-based photosensitiser using a bifunctional linker consisting of a bis(bromomethyl)phenyl unit and an ortho-phthalaldehyde unit. This cell-based photosensitiser with surface modification with cyclic RGD peptide moieties can selectively bind against the αvβ3 integrin-overexpressed cancer cells, leading to enhanced photocytotoxicity. The results demonstrate that this facile strategy is effective for live-cell surface modification for a wide range of applications.