More than thirty years after Quantum Cromody namics (QCD) was first proposed as the fundamental theory of the strong force, very little is still known about the dynamical basis of hadron structure. How do these fundamental degrees of freedom dynamically generate the mass, spin, motion and spatial distribution of color charges inside hadrons? To investigate these fundamental questions a new electron-protonlelectron-ion collider is proposed (EIC). The inner tracking system of the detectors in these colliders will require very high granularity, low material budget and, radiation hard design. In this talk, it will be shown that monolithic active pixel silicon detectors (MAPS) with sensors based on a CMOS technology satisfy all these requirements and test results will be provided. An overview will be given on eRHIC: a EIC facility designed to be realized in the Brookhaven National Laboratory, on the tests ongoing in Brookhaven National Laboratory and Columbia University on two MAPS prototype MIMOSA-26.