A nanostructured molecular delivery vehicle comprising magnetic materials and configured to receive passenger biomolecules. The application of a an appropriate magnetic field having a gradient orients and drives the vehicle into a biological target, which may comprise cells, cell masses, tissue slices, tissues, etc. Under the control of the magnetic field, these vehicles can penetrate cell membranes. Then, the biomolecules carried by the vehicle can be released into the cells to perform their functions. Using this “nanospearing” technique, unprecendented high transfection efficiency has been achieved in several difficult-to-transfect cells. These include, but are not limited to, Bal 17 cells, ex vivo B cells, primary cultured cortical neurons, etc. This method advances the state of the art, providing an improved technique for the introduction of exogenous molecules to cells, with the clinical applications including, but not being limited to, drug delivery, gene therapy, vaccination, etc.