A low cytotoxic porous zinc-adeninate metal-organic framework carrier: pH-triggered drug release and anti-breast cancer study

Abstract

In this study, a new zinc-based porous metal-organic framework (MOF) [Zn2(ad)2(hmdb)(H2O)](DMF)2(H2O) based on zinc(II) ions, biomolecular adenine (Had) and 4,4′-(hydroxymethylene)dibenzoic acid (H2hmdb) has been successfully prepared under solvothermal conditions. The X-ray study reveals that compound 1 belongs to the monoclinic space group C2/c and reveals a three-dimensional channel-type neutral framework. This MOF exhibits low toxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Due to its suitable channel size and good stability in biological buffer solution, the activated 1 has been used as a carrier for loading the anticancer drug 5-Fu (5-fluorouracil) though a simple adsorption process. The successful loading of 5-Fu was confirmed by the gas sorption measurement and the loading capacity was characterized by UV–Vis spectroscopy, which reveal a drug loading of 32.2 wt%. The drug delivery in the simulated cancerous tissues (pH = 5.0) exhibited a more effective release in comparison with that in the normal tissues (pH = 7.4), demonstrating a physiological pH-responsive drug release. Furthermore, in vitro cytotoxicity of 1 and 5-Fu loaded 1a was also evaluated using MTT assays against HepG2 and MCF-7 cells. A new zinc-based porous metal-organic framework (MOF) has been successfully prepared under solvothermal conditions. Due to its suitable channel size and good stability in biological buffers solution, compound 1 has been used as a carrier for loading the anticancer drug 5-Fu (5-fluorouracil) though a simple adsorption process. The drug-loaded MOF demonstrates a physiological pH-responsive drug release.