A Luminescent Mg-MOF for sustained release of 5-fluorouracil: appropriate host-guest interaction and satisfied acid-base resistance

It is important to achieve moderate sustained release rate for drug delivery, and so it is critical to regulate the host-guest interactions for the rational design of carrier. In this work, a nano-sized biocompatible MOF, Mg(H2TBAPy)(H2O)3·C4H8O2 (TDL-Mg), was constructed by employing π-conjugated 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) as ligand and used for 5-fluorouracil (5-FU) loading (28.2 wt%) and sustained slow release. TDL-Mg exhibits a 3D supramolecular architecture featuring 1D rectangle channel with a size of 6.2 × 8.1 A2 and a BET surface area of 627 m2·g-1. Channel microenvironment analysis shows that the rigid H2TBAPy2- ligand adopts special torsion to stabilize the channels and offer rich π-binding sites; the partially deprotonated carboxyls not only participate in the formation of strong hydrogen bonds but also create a mild pH buffer environment for biological applications. Suitable host-guest interactions are generated by the synergistic effect of polydirectional hydrogen bonds,...