title: Effect of liposome charge and PEG polymer layer thickness on cell-liposome electrostatic interactions.
abstract: Targeted drug delivery requires binding to (and subsequent uptake by) the carrier and target cell. In this paper, we calculate the work required to bring into contact liposomal carriers and cells as a function of the liposome and cell electrostatic characteristics. We find that cell-liposome adhesion is sensitive to the cell type and optimized at a cell to liposome charge ratio which depends on the degree of cell charge regulation. As a result, uptake (which is dependent on the occurrence of binding) is also optimized. Incorporation of a (poly)ethylene glycol (PEG) layer enhances liposome adhesion in cases where the cell-liposome interactions are repulsive, and suppresses adhesion in systems where the interactions are attractive. Our results, which are in agreement with experimental observations, show that electrostatic interactions may be designed to enable targeted drug delivery by liposomes to a specific cell population.
authors.affiliation: Department of Chemical Engineering, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA. Dan@coe.drexel.edu
authors.forename: Nily
authors.initials: N
authors.lastname: Dan
mesh_terms: D002448:Cell Adhesion; D016503:Drug Delivery Systems; D015195:Drug Design; D008081:Liposomes / Q000737:chemistry*; D008956:Models, Chemical; D011092:Polyethylene Glycols / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D008081:Liposomes; D011092:Polyethylene Glycols