1) Liposomes functionalized with phosphatidic acid (PA) were developed that bind amyloid-beta (Aβ) peptide and rescue neurons from Aβ toxicity in vitro. 2) The liposomes were further modified with ligands like ApoE peptides or antibodies to target the blood-brain barrier (BBB) and were shown to cross an in vitro BBB model. 3) Treatment of an Alzheimer's disease mouse model with the ApoE-functionalized PA-liposomes reduced brain Aβ levels by 40% and almost completely recovered cognitive deficits, potentially by facilitating Aβ clearance from the brain to the liver and spleen.