Coupling magnetic nanoparticles to gene vectors results in hundreds-fold increase of the uptake of these vectors on a time scale of minutes, thus leading to high transfection efficiency. Gene vector and magnetic nanoparticle complexes are transfected into cells after 10–15 minutes, which is faster than the 2–4 hours that other transfection methods require. After 24, 48 or 72 hours, most of the particles are localized in the cytoplasm, in vacuoles (membranes surrounded structure into cells) and occasionally in the cell nucleus.