Improving The Brain Delivery of Gold Nanoparticles by Conjugation with An Amphipathic Peptide

Abstract

In this article, we have shown that conjugation of 12 nm GNPs with the amphipathic peptide CLPFFD increases the in vivo penetration of these particles to the rat brain. The C(GNP)-LPFFD conjugates showed a smaller negative charge and a greater hydrophobic character than citrate-capped GNPs of the same size. We administered intraperitoneal injections of citrate GNPs and C(GNP)-LPFFD in rats, and determined the gold content in the tissues by neutron activation. Compared with citrate GNPs, the C(GNP)-LPFFD conjugate improved the delivery to the brain, increasing the concentration of gold by fourfold, while simultaneously reducing its retention by the spleen 1 and 2 h after injection. At 24 h, the conjugate was partially cleared from the brain, and mainly accumulated in the liver. The C(GNP)-LPFFD did not alter the integrity of the blood-brain barrier, and had no effect on cell viability.