Loading co-amorphous on Metal-Organic Frameworks for gelation elimination and anti-cancer drug delivery enhancement

Troublesome gelation occurring during the dissolution of special co-amorphous (COAM) systems poses a limitation on their further applications. Metal-Organic Frameworks (MOFs) are promising porous materials for nano-scale drug delivery due to their high loading capacity and ability to control drug release. Examples of MOFs as drug carriers with the confinement effect for COAM drugs have never been reported. In this study, to eliminate the gelation of the COAM of an anti-cancer drug gefitinib (GTB) and co-former saccharin (SAC) for enhancing their anti-cancer drug delivery, a Zr-based MOF, nanoUiO-67, was selected as drug carrier. The loading process of GTB-SAC COAM on nanoUiO-67 was revealed via a real-time spinning disk confocal fluorescence microscope. The maintenance of molecular interactions between GTB and SAC in GTB-SAC COAM after loaded on nanoUiO-67 was proven experimentally and computationally, along with the host (nanoUiO-67)-guest (drug) interactions. The combined advantages of porous materials nanoMOFs and GTB-SAC COAM were fully demonstrated in terms of excellent physical stability, desirable drug release, good bio-compatibility and higher cytotoxicity towards HeLa cells. It is expected that this novel strategy could have potential application in gelation elimination and developing multi-component drug-loaded MOFs.