Efficient DNA ligation by selective heating of DNA ligase with a radio frequency alternating magnetic field.

We present a simple method for efficient DNA ligation utilizing the heat generation of ferromagnetic particles subjected to an ac magnetic field. We carry out the ligation of DNA fragments with cohesive ends using T4 DNA ligase immobilized on the surface of ferromagnetic particles. When a radio frequency alternating magnetic field is applied, ferromagnetic particles dissipate heat and DNA ligase on the particles is selectively heated up and activated with little influence on the annealing of DNA ends, as a result of which the ligation efficiency increases. We show that the ligation efficiency increases with an increase in the field amplitude.