Construction And Application For Cancer Therapy And Gas Separation Of Hydrogen-bonded Organic Frameworks

Hydrogen bonding plays a critical role in biological systems for both structure and functionality,which has inspired chemists to construct hydrogen-bonded organic frameworks(HOFs),which is a kind of pore organic crystalline materials constructed through weak non-covalent bonds,such as hydrogen bonds.Same as other periodic frameworks for example metal-organic frameworks(MOFs),zeolite-imidizol frameworks(ZIFs),and covalent organic frameworks(COFs),HOFs has the merits of high surface area,predictable structure and tunable pore size/shape.Beyond that,the hydrogen bonding endows HOFs some unique traits such as mild synthetic conditions,solution processability,and easy regeneration.More strikingly,HOFs materials possess good biocompatibility and low toxicity attributed to the metal-free property of components,which is an excellent candidate for drug delivery and biological application.Despite many obvious advantages,the field of HOFs is still in its early stage especially when compared with the impressive success of the well-established MOFs,ZIFs and COFs.This is because the hydrogen bonds in HOFs are too weak to stabilize the frameworks,and therefore the HOFs structures usually collapse upon solvent removal.The low stability severely compromises its intrinsic merits and encumbers the potential application of HOFs.On the basis of the above consideration,this thesis mainly focuses on the construction of robust hydrogen-bonded organic framework materials through several approaches.Resultant HOFs possessed suitable pore size and controllable material particle size to load commercial DOXO to successfully realize synergistic chemo-photodynamic therapy,as well as construction of a novel hierarchical meso-microporous hydrogen-bonded organic framework for gas adsorption and separation.It is critically important to synthesis organic building blocks with multiple group and large ?-stacking interaction to construct robust HOFs.In this thesis,we present the successfully construction of three novel hydrogen-bonded organic frameworks through reasonable design.According to these structures for exhaustive analysis,their gas properties were investigated.The main results are summarized as follows:1.The stability of Hydrogen-Bonded Organic Frameworks(HOFs)is a great issue hindering their wide application.Herein,we describe a rational approach for construction of stable HOFs through combination of the multiple hydrogen bonding,?-71 interactions as well as the residual hydrogen donor/acceptor groups.The resultant compound PFC-1 exhibits high surface area of 2,122 m2/g and excellent chemical stability of being intact in concentrated HCl for at least 117 days.Notably,we demonstrate a methodology of acid-assistant crystalline redemption to recover the thermal damage to PFC-1.With periodical integration of the photosensitizing moiety in the robust framework,PFC-1 can efficiently encapsulate Doxorubicin drug for synergistic chemo-photodynamic therapy,which displays comparable therapeutic efficacy as the only Doxo chemotherapy but lower cytotoxicity due to the non-metal and low-toxic components.With overcoming the limitation of stability,this work promises the possibilities of HOFs for a wide range of application.2.We construct a novel three-dimension(3D)hydrogen-bonded organic framework(PFC-2)with a hierarchical meso-microporous structure,which possesses the largest open channels relative to all known HOFs and exhibits highly selective separation of acetylene and ethylene versus methane at ambient atmosphere.Comparison on the adsorption behaviors of PFC-2 and an analogue structure PFC-1 clearly shows that the extensively existed unpaired hydrogen bond acceptor C=O groups in PFC-2 dramatically increase the affinity between gas molecules and frameworks,resulting in high isosteric heats of adsorption(Qst)and better selectivity toward C2 hydrocarbons to methane.The study presented here demonstrated an effective strategy to optimize gas adsorption/separation performance of HOF materials.3.A robust microporous porphyrin-based hydrogen-bonded organic framework(HOF),named PFC-5,has been successfully constructed.Based on hydrogen-bonding and ?-? interaction,PFC-5 exhibits good water,thermal and chemical stability.PFC-5 possesses permanent microporosity as demonstrated in the single-crystal X-ray diffraction analysis and experimental CO2 sorption.The activated material has been developed for highly selective separation of C2 light hydrocarbons/methane at room temperature and normal pressure.