Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

The design of a non-viral gene delivery system that can release a functional nucleic acid at the intracellular destination site is an exciting but also challenging proposition. The ideal gene delivery vector must be non-toxic, non-immunogenic, overcome extra- and intra-cellular barriers, protect the nucleic acid cargo from degradation with stability over a range of temperatures. A new 15 amino acid linear peptide termed CHAT was designed in this study with the goal of delivering DNA with high efficiency into cells in vitro and tissues in vivo. Rational design involved incorporation of key amino acids including arginine for nucleic acid complexation and cellular uptake, tryptophan to enhance hydrophobic interaction with cell membranes, histidine to facilitate endosomal escape and cysteine for stability and controlled cargo release. Six linear peptides were synthesised with strategic sequences and amino acid substitutions. Data demonstrated that all six peptides complexed pDNA to produce cationic nanoparticles less than 200 nm in diameter, but not all peptides resulted in successful transfection; indicating the influence of peptide design for endosomal escape. Peptide 4, now termed CHAT, was non-cytotoxic, traversed the plasma membrane of breast and prostate cancer cell lines, and elicited reporter-gene expression following intra-tumoural and intravenous delivery in vivo. CHAT presents an exciting new peptide for the delivery of nucleic acid therapeutics.

Original publication




Journal article


Journal of controlled release : official journal of the Controlled Release Society

Publication Date





1288 - 1299


School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK.


Gene Transfer Techniques, Transfection, Plasmids, Cell-Penetrating Peptides, Genetic Therapy