A porous, molecularly imprinted polymer and a process for its preparation are described. The porous, molecularly imprinted polymer is characterized in that it is obtainable by providing a porous silica; attaching a molecular template to the surface of the porous silica; filling the pores of the porous silica with a polymer, removing the silica and the molecular template, thereby leaving a porous, molecularly imprinted polymer. The process is characterized by the above defined process steps. Also described are a porous polymer vesicle and its preparation with the same features as defined for the porous, molecularly imprinted polymer and its preparation, except for the lack of the molecular template and thus the lack of the molecular imprint in the porous polymer.