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This article presents an interesting study on molecular self-assembly and its effect on steric recognition by molecularly imprinted polymers. With S-naproxen as the template and acrylamide as the functional monomer, the self-assembly appears to play important roles in the selective adsorption, affecting not only the adsorption amount but also the enantioselective recognition. Both of them become evident by the change of monomer-template ratio. An increase in the monomer-template ratio will result in a higher level of adsorption. The best selectivity for steric recognition is, however, shown at an optimal composition (corresponding to the saturation interaction of monomer and template). A higher or lower monomer-template ratio leads to a dramatic decrease in this selectivity. Related information indicates that this may be a result from the matched arrangement between the binding sites and the template, which makes the binding sites capable of selectively recognizing the imprint species.

Membrane separation technology is an energy-efficient and green separation technology for purifying and concentrating active pharmaceutical ingredients (APIs) from organic solvents during the synthesis process. However, the lack of highly permeable materials with high rejection performance toward target molecules impedes the worldwide application of the membrane separation technology to reduce the cost of the separation process on a large scale. In the current study, we develop highly permeable thin-film nanocomposite (TFN) membranes through incorporating poly(sodium methacrylate) (SPA)-grafted UiO-66 into the polypyrrole selective layer, clarifying the effects of preparation conditions on the performance of the TFN membranes and optimizing the operation conditions on the separation performance of the TFN membranes. With finely tailored membrane structure and affinity between the TFN membranes and the solvents, the optimized TFN membranes demonstrate solution permeance as high as 88.8 L m −2 h −1 bar −1 with a rejection of about 99.9% toward octreotide acetate, exhibiting excellent rejection performance toward polypeptides and antibiotics. In the continuous operation mode, the TFN membranes still demonstrate stable permeance as high as 56.5 L m −2 h −1 bar −1 , which is about 1 order of magnitude higher than that of commercial polyamide membranes, showing strong potential in purifying and concentrating APIs from organic solvents.

Based on the establishment of the geometry and equations of non-contact vortex gripper, the numerical analysis of the internal flow field characteristics and the key parameters affecting the adsorption performance was carried out. The results showed that: for the single air-entrance gripper, the negative pressure center not coincides at the geometric center of the gripper. Besides, with the movement of swirling flow, the position of the negative pressure center transformed; When the geometric parameters and working conditions are fixed, there is the most suitable air gap making the maximum value of negative pressure and adsorption force; Compared to single air-entrance gripper, double air-entrance gripper have better adsorption stability.