Coordination-directed Assembly Of 1-D And 1-D Derived Metal-biomolecule Frameworks

Metal-biomolecule frameworks(MBioFs) are a class of metal-organic frameworks(MOFs) using biomecules as organic linkers. Compared with the commonly used ligands, biomolecules have many different metal-binding sites providing multiple coordination modes, and thus increased the structure diversity of MBioFs. Furthermore, some chiral bio molecules can be utilized to fabricate chiral MBioFs for potential applications in the fields of highly-specific recognition, separation and catalysis. Most importantly, the MBioFs are more suitable for biological applications, such as drug delivery, based on their biologically and environmentally compatible properties.In this study, a series of one dimensional(1-D) and 1-D derived MBioFs were constructed through a solution-based assembly process using biomolecules as organic linkers. The effect of molecular structures on the assembly processes was investigated tentatively. Then, the effect of kinetic factors on the assembly and final morphologies of the MBioFs was investigated. At last, the selective adsorption properties of one MBioFs to dyes and proteins were investigated for further applications in the treatment of waste water and separation of biomacromolecules.The main contents in this study were summarized as follows:Firstly, a series of I-D nanofibers were constructed using dicarboxylic ?-amino acids and C u(II) as ligands. The effect of carbon chain length and chirality on the assembly process and final morphologies of the MBioFs were studied. Results showed that the formation of stereoselective hydrogen interactions between the coordination polymer chains is critical for the formation of the nanofibers. When chiral aspartic acids, chiral 2- aminoadipic acids and racemic glutamic acid were used as organic linkers, hydrogen bonds could be formed between the 1-D coordination polymer chains, which lead the aggregation of the coordination polymer chains to form the nanofibers. The chemical compatible and structural complementarity between amino acids of the coordination polymer chains both influenced the assembly process of the nanofibers.Secondly, a series of ?? ?-dicarboxylic acids were used as organic linkers to coordinate with Cu(II), and MBioFs with different morphologies were formed. Results showed that nanofibers were formed only when succinate was used as organic linker. Porous microspheres were obtained when oxalic acid was used as organic linker, and amorphous precipitate was obtained when glutaric acid or adipic acid was used as organic linker. Compared with dicarboxylic ?-amino acids, the absent of amino group changed the interactions between the coordination polymer chains and thus influenced the morphologies of the MBioFs.Lastly, based on the fact that succinate can coordinate with Cu(II) to form nanofibers, the influence of kinetic factors on the assembly process and final morphology of succinate-Cu(II) MBioFs were further investigated. It was found that when the concentration of the reactants solution was low, discrete nanofibers were obtained through a reaction- limited assembly process. While, when the concentration of the reactant solution was high, symmetrical microclusters were obtained through a diffusion- limited assembly process. Specially, mask- like double hole symmetrical microclusters(MDHSMs) were obtained when the concentration of the reactants was 140 mM. The influence of biomacromolecules, stirring, and diffusion interface on the assembly process and final morphology of succinate-Cu(II) MBioFs was investigated successively. The MDHSMs was then applied in the selective adsorption of dyes and proteins, which made the MDHSMs promising candidate for the treatment of waste water and separation of biomolecules.