Methods of post-loading ceramic particles with antimicrobial metal cations are disclosed. In certain embodiments, the post-loaded particles are zeolites, wherein the zeolites have been incorporated into a resin and the combination is used as an implantable device. In certain embodiments, the polymer is a thermoplastic polymer such as polyaryletheretherketone (PEEK). In certain embodiments, the source of antimicrobial activity includes ion-exchangeable cations contained in a zeolite. In certain embodiments, disclosed are methods of imparting antimicrobial activity to devices by controlling the delivery of certain cations through ion-exchange via a zeolite incorporated in the device.