Targeted Adsorptive Removal of Nonsteroidal Anti-inflammatory Drugs for Water Purification Using Nanoporous Zr-Based Metal–Organic Framework Microcubes

Chemically synthesized drugs used in the industry are associated with potential environmental risks. Herein, we report the targeted adsorption of nonsteroidal anti-inflammatory drugs, with and without a carboxylic acid group, using a water-stable Zr-based porphyrinic metal–organic framework (MOF), PCN–224. Nanoporous PCN–224 contains interaction sites for drugs and thus enables the removal of organic pollutants. The removal efficiency of NPX and IBP was 96 and 94%, but PCN–224 removed only 37% of SMX from water. The apparent difference in the adsorption efficiency of PCN–224 indicates that the carboxylic acid functional groups in drugs strongly interacted with the open metal sites of the PCN–224 Zr6 node via coordination bonding, resulting in a high adsorption capacity. This discovery provided a practical approach for the selective adsorptive removal of various other drugs with carboxylate groups.