The invention relates to an electromagnetic resonator that comprises a housing (1) for a conductor and active ingredient. The novelty lies in the conductor being a cylindrical spiral element (3) positioned on at least one support (2), the natural frequency of the electromagnetic resonator is from 0.1 to 10 MHz, the support (2) comprises a cavity (4) for the active ingredient (5) and the active ingredient has been positioned in the geometric centre of the electromagnetic resonator.
