The present invention discloses a method of delivering a macromolecule to a cell, comprising engaging the macromolecule to a nanotube wherein the nanotube comprises a magnetic particle, placing the nanotubes into a sample wherein the sample comprises a plurality of cells and applying a force to the sample wherein the force causes the nanotubes to collide with the cells and thereby spear the cells. The method further discloses applying a second force which drives the nanotubes into the cell. Furthermore, the invention discloses a method of transfecting and/or transducing a cell, comprising engaging a macromolecule to a nanotube, placing the nanotubes into communication with the cells and applying a force to the nanotubes which causes the nanotubes to collide with the cells and thereby pierce the cellular membrane. Once inside the cell, the macromolecule may disengage from the nanotube.
 The invention was supported, in whole or in part, by the U.S. Department of Energy (DE-FG02-00ER45805), the National Science Foundation (NIRT 0304506), and the National Institutes of Health (AI-34586). The Government has certain rights in the invention.