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Persistent organic pollutants (POPs) exist widely in the environment and place significant impact on human health by bioaccumulation. Efficient recognition of POPs and their removal are highly challenging tasks because their specific structures interact often very weakly with the capture materials. Herein, a molecular nanocage (1) is studied as an efficient sensing and sorbent material for POPs, which is demonstrated by a representative and stable perfluorooctane sulfonate (PFOS) substrate containing a hydrophilic sulfonic group and a hydrophobic fluoroalkyl chain. A highly sensitive and unusual turn-on fluorescence response within 10 s and a 97% total removal of PFOS from water in 20 min have been achieved owing to the strong host–guest interactions between 1and PFOS. The binding constant of 1to PFOS is 2 orders of magnitude higher than state-of-the-art adsorbents for PFOS and thus represents a new benchmark material for the recognition and removal of PFOS. The host–guest interaction has been elucidated by solid-state NMR spectroscopy and single-crystal X-ray diffraction, which provide key insights at a molecular level for the design of new advanced sensing/sorbent materials for POPs.

Removal of trace SO2contaminants from gas mixtures by the molecular sieving effect is highly desired. Herein, a microporous metal–organic framework Cu2(pzdc)2(pyz) [CPL-1, pzdc = 2,3-pyrazinedicarboxylate; pyz = pyrazine] with a dumbbell-shaped 1D channel and specific binding sites is explored for deep desulfurization. The proper size of 4.1 × 6.2 Å and strong SO2trapping sites on CPL-1 render a high adsorption uptake of SO2(44.8 cm3g–1) with a record-high selectivity for SO2/N2(368) and SO2/CH4(74.3) separation under ambient conditions. Moreover, the dispersion-corrected density functional theory calculations have identified the dual specific adsorption sites of SO2, such as Sδ+···Oδ−electrostatic interactions and Oδ−···Hδ+hydrogen bonds. The feasibility of CPL-1 for SO2/N2, SO2/CH4, CO2/CH4, CO2/N2, and mimicked flue gas mixture separations was validated by dynamic breakthrough experiments. Water vapor and CO2impurity were introduced to the gas feed streams to confirm the excellent separation performance of CPL-1. Moreover, a scale-up production of CPL-1 via a facile and green method was conducted, and a reproducible CPL-1 adsorbent with undamaged adsorption and separation performances was successfully manufactured in kilogram quantity. These unique features render CPL-1 a very promising adsorbent for practical desulfurization processes.

An ideal anticancer drug release system is designed to release drugs over a prolonged period while minimizing the initial burst to significantly reduce the side effects and the number of medications. In this study, CaCO3particles (average diameter 800-1600 nm with PDI < 0.2) aiming at such controlled release system were successfully prepared via Flash Nano Precipitation technique. Hydroxypropyl methylcellulose and sodium dodecyl sulfate were both employed as additives for CaCO3crystallization to promote the formation of vaterite and convex-disc-shaped CaCO3, and at the same time as stabilizers for CaCO3particles to control particle growth and avoid particle agglomeration. By using the as-prepared vaterites, a satisfying drug loading capacity (~0.1 mg drug/mg particle) was realized, and prolonged drug release was achieved with a low initial release (< 10% within 1 day at pH = 6.0) and approximately zero-order release kinetics before 36 h (R2 > 0.97) or after 36 h (R2 > 0.99). Besides, by changing the particle size, different drug release kinetics could be achieved while the high drug loading capacity and low initial release were both maintained. The vaterite particles prepared in this work could be a potential candidate drug carrier for extended drug release with minimized initial burst and a constant drug releasing rate.