A Large Capacity Cationic Metal-Organic Framework Nanocarrier for Physiological pH Responsive Drug Delivery

A nanoscale cationic porous drug carrier ZJU-101 (ZJU = Zhejiang University), synthesized by the solvothermal method to get the crystal size of similar to 300 nm, was used to load diclofenac sodium, an anionic drug. This positively charged host materials showed a large loading capacity of diclofenac sodium (similar to 0.546 g/g) through ion exchange and penetration procedures. The drug delivery in the inflamed tissues (pH = 5.4) exhibited a more effective release in comparison with that in the normal tissues (pH = 7.4), demonstrating a physiological pH responsive drug release. This discriminating drug release process was controlled by anion exchange between anions in phosphate buttered saline (PBS) and coordinated/free diclofenac anions.