Well, I guess you could do this with mesoporous silica

mesoporous silica and pegylation

Catechols serve as excellent anchor groups for surface functionalization of iron oxide nanoparticles. You could take a catechol derivative such as 3,4-dihydroxybenzoic acid and conjugate it to your drug(s) using metabolically labile linker such as an ester or carbamate, then directly attach your catechol-drug conjugate to the surface.