Magnetofection: The Use of Magnetic Nanoparticles for Nucleic Acid Delivery

INTRODUCTION

Magnetofection is defined as nucleic acid delivery guided and mediated by magnetic force acting on associations of magnetic particles and nucleic acids or nucleic acid vectors. Vectors are bound to magnetic, usually iron oxide, nanoparticles, in most cases by noncovalent bonds. Magnetic force accumulates and/or holds magnetic vectors in a target tissue against hydrodynamic forces. In cell culture, magnetic vectors are magnetically sedimented on the target cells within minutes. Thus, the diffusion barrier to nucleic acid delivery is overcome, the full vector dose comes in contact with the target cells, and introduction of genetic material is synchronized. Nucleic acid delivery is greatly accelerated and its efficiency with many, if not most, vector types is improved. Magnetofection is applicable to small and large nucleic acids. Other advantages include low-dose requirements, the possibility of confining nucleic acid introduction to a localized area (magnetic targeting), and the amenability to high-throughput automation. Due to the favorable dose-response profile and the rapid kinetics, vector-related toxicity can be kept low. This protocol describes the use of magnetic nanoparticles for delivery of nucleic acid to target cells, using either nonviral or viral vectors.