Multifunctional\nNanoparticles by Coordinative Self-Assembly\nof His-Tagged Units with Metal–Organic Frameworks

Abstract

Self-assembly of\nindividual units into multicomponent complexes\nis a powerful approach for the generation of functional superstructures.\nWe present the coordinative interaction of oligohistidine-tags (His-tags)\nwith metal–organic framework nanoparticles (MOF NPs). By this\nnovel concept, different molecular units can be anchored on the outer\nsurface of MOF NPs in a self-assembly process generating multifunctional\nnanosystems. The article focuses on two main objectives: first, the\ndetailed investigation of the assembly process and fundamental establishment\nof the novel functionalization concept; and second, its subsequent\nuse for the development of biomacromolecule (e.g., peptides and proteins)\ndelivery vehicles. Three exemplary MOF structures, MIL-88A, HKUST-1,\nand Zr-<i>fum</i>, based on different metal components,\nwere selected for the external binding of various His-tagged synthetic\npeptides and recombinant or chemically H₆-modified proteins.\nEvidence for simultaneous assembly of different functional units with\nZr-<i>fum</i> MOF NPs as well as their successful transport\ninto living cells illustrate the promising potential of the self-assembly\napproach for the generation of multifunctional NPs and future biological\napplications. Taking the high number of possible MOF NPs and different\nfunctional units into account, the reported functionalization approach\nopens great flexibility for the targeted synthesis of multifunctional\nNPs for specific purposes.