A water stable metal–organic framework with 1D nanotube pores for 5-fluorouracil delivery and anti-brain tumor activity

Abstract

The employment of porous carriers for anticancer drug delivery has gained much attention in recent years for their excellent drug-loading capacity and controlled release performance. In this work, by utilizing a rigid organic aromatic carboxylic acid ligand, a new Zn(II)–organic framework {[Zn₂(bptc)(H₂O)]·(DMAc)₃(H₂O)₄}_n (1, DMAc is in short of N,N-dimethylacetamide, H₄bptc is in short of biphenyl-3,3′,5,5′-tetracarboxylic acid ligand), with considerable water stability has been prepared using the solvothermal technology. The structural analysis result reveals that complex 1 is constructed from fourfold helical metal chains whose net could be simplified into a (6,8)-connected topology. Moreover, complex 1 shows 1D nanotube channels with a window size of 10.7 × 10.7 Å² along the [001] direction and reveals a large accessible voids of 51.7%. The desolvated 1 (1a) was used to study the loading and releasing of the 5-fluorouracil (5-Fu), which reveals that 1a could uptake around 51.2 wt% of 5-Fu and nearly 85.6% of the absorbed 5-Fu could be released in PBS (7.4 for the pH value) in 100 h at 37 °C. In connection to these, in vitro cytotoxicity of compound 1 together with the anticancer performance of 5-Fu-loaded 1a was evaluated against human oral epidermal cells and human brain tumor cells SF17 via MTT assays.