The present invention relates to mucosal immune protection, mucosal vaccine delivery, and mucosal drug delivery. Novel calcium phosphate core particles, particularly nanoparticles are used as vaccine adjuvants and compositions for inducing protective mucosal immunity. Methods of inducing an immune response to an antigen by delivering the antigen to a mucosal surface using the particles of this invention, and to methods of making such particles are also provided. The particles of this invention are also useful for delivering compositions, such as a pharmacologically active agent, to the mucosal surfaces of a patient in need thereof, to methods of delivering such compositions, and to methods of making such particles.