The project AMIGA (Analysis of the interstellar medium of isolated galaxies) will provide a statistically significant sample of the most isolated galaxies in the northern sky. Such a control sample is necessary to understand the role of the environment in evolution and galaxy properties like the interestelar medium (ISM), start formation and nuclear activity. The sample is based on the CIG catalog (Karachentseva 1973) and the data base includes blue luminosity, near-infrared luminosity, far-infrared (FIR) emission, atomic gas (HI) emission, radio continuum, and, for a red-shift limited subsample of 200 galaxies, CO and Ha emission. The data is being released and periodically updated at http://www.iaa.csic.es/AMIGA.html. One of our main goals is the study of the triggering of nuclear activity in non-interacting galaxies using diferent methods. We will focus on the well known radiocontinuum-FIR correlation in order to find radio-excess galaxies which are candidates to host an active galactic nucleus (AGN) and FIR colors to find obscured AGN candidates. We have looked for the existing information on nuclear activity in the Véron-Cetty catalogue and in the NASA Extragalactic Database (NED). Finally we have produce a final catalogue of AGN candidate galaxies which will provide a baseline for the study of the nuclear activity depending on the galaxy-galaxy interaction.