Dual-Functionalized Magnetic Metal–Organic Framework for Highly Specific Enrichment of Phosphopeptides

The highly specific enrichment of phosphoproteins and phosphopeptides from intricate biological systems is the precondition of in-depth phosphoproteome research. Herein, a novel dual-functionalized magnetic zirconium-based metal–organic framework (MOF) denoted as DFMMOF, with the purpose of combining the affinity of immobilized metal ion affinity chromatography (IMAC) and metal oxide affinity chromatography (MOAC) has been successfully synthesized. The inherent Zr–O cluster of DFMMOF particles acted as MOAC and the immobilized titanium­(IV) ions served for IMAC. The obtained DFMMOF exhibited rapid magnetic separation (within 5 s), large surface area (237.9 m² g^–1), high binding capacity (100 mg g^–1), and good postenrichment recovery (84.8%). Thanks to the strong affinity, low detection sensitivity (5 fmol) and high selectivity (β-casein/BSA with a molar ratio of 1:1000) for phosphopeptide enrichment were obtained using DFMMOF as absorbent. Moreover, the effective identification of phosphopeptides from real samples (human serum and nonfat milk) further confirmed the immense potential of DFMMOF as a promising candidate for the detection and extraction of trace amounts of phosphorylated peptides in complex biosamples

Fluorinated Nonporous Adaptive Cages for the Efficient Removal of Perfluorooctanoic Acid from Aqueous Source Phases

Per- and polyfluoroalkyl substances (PFAS) accumulate in water resources and pose serious environmental and health threats due to their nonbiodegradable nature and long environmental persistence times. Strategies for the efficient removal of PFAS from contaminated water are needed to address this concern. Here, we report a fluorinated nonporous adaptive crystalline cage (F-Cage 2) that exploits electrostatic interaction, hydrogen bonding, and F–F interactions to achieve the efficient removal of perfluorooctanoic acid (PFOA) from aqueous source phases. F-Cage 2 exhibits a high second-order kobs value of approximately 441,000 g mg–1 h–1 for PFOA and a maximum PFOA adsorption capacity of 45 mg g–1. F-Cage 2 can decrease PFOA concentrations from 1500 to 6 ng L–1 through three rounds of flow-through purification, conducted at a flow rate of 40 mL h–1. Elimination of PFOA from PFOA-loaded F-Cage 2 is readily achieved by rinsing with a mixture of MeOH and saturated NaCl. Heating at 80 °C under vacuum then makes F-Cage 2 ready for reuse, as demonstrated across five successive uptake and release cycles. This work thus highlights the potential utility of suitably designed nonporous adaptive crystals as platforms for PFAS remediation