RESUMEN
Thin-film composite (TFC) membranes have gradually replaced some traditional technologies in the extraction, separation, and concentration of high value-added pharmaceutical ingredients due to their controllable microstructure. Nevertheless, devising solvent-stable, scalable TFC membranes with high permeance and efficient molecule selectivity is urgently needed to improve the separation efficiency in the separation process. Here, we propose phenolphthalein, a commercial acid-base indicator, as an economical monomer for optimizing the micropore structure of selective layers with thickness down to 30 nanometers formed by in situ interfacial reactions. Molecular dynamics simulations indicate that the polyarylate membranes prepared using three-dimensional phenolphthalein monomers exhibit tunable microporosity and higher pore interconnectivity. Moreover, the TFC membranes show a high methanol permeance (9.9 ± 0.1 liters per square meter per hour per bar) and small molecular weight cutoff (≈289 daltons) for organic micropollutants in organic solvent systems. The polyarylate membranes exhibit higher mechanical strength (2.4 versus 0.8 gigapascals) compared to the traditional polyamide membrane.
RESUMEN
Ageing has been identified as an independent risk factor for various diseases; however, the physiological basis and molecular changes related to ageing are still largely unknown. Here, we show that the level of APPL2, an adaptor protein, is significantly reduced in the major organs of aged mice. Knocking down APPL2 causes premature ageing of human umbilical vein endothelial cells (HUVECs). We find that a lack of T04C9.1, the homologue of mammalian APPL2, leads to premature ageing, slow movements, lipid deposition, decreased resistance to stresses, and shortened lifespan in Caenorhabditis elegans (C. elegans), which are associated with decreased autophagy. Activating autophagy by rapamycin or inhibition of let-363 suppresses the age-related alternations, impaired motility, and shortened lifespan of C. elegans, which are reversed by knocking down autophagy-related genes. Our work provides evidence that APPL2 and its C. elegans homologue T04C9.1 decrease with age and reveals that a lack of T04C9.1 bridges autophagy decline and ageing in C. elegans.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Autofagia , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Longevidad , Animales , Humanos , Ratones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Envejecimiento/genética , Envejecimiento Prematuro/genética , Autofagia/genética , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Longevidad/genéticaRESUMEN
The precise manipulation of the microstructure (pore size, free volume distribution, and connectivity of the free-volume elements), thickness, and mechanical characteristics of membranes holds paramount significance in facilitating the effective utilization of self-standing membranes. In this contribution, the synthesis of two innovative ester-linked covalent-organic framework (COF) membranes is first reported, which are generated through the selection of plant-derived ellagic acid and quercetin phenolic monomers in conjunction with terephthaloyl chloride as a building block. The optimization of the microstructure of these two COF membranes is systematically achieved through the application of three different interfacial electric field systems: electric neutrality, positive electricity, and negative electricity. It is observed that the positively charged system facilitates a record increase in the rate of membrane formation, resulting in a denser membrane with a uniform pore size and enhanced flexibility. In addition, a correlation is identified wherein an increase in the alkyl chain length of the surfactants leads to a more uniform pore size and a decrease in the molecular weight cutoff of the COF membrane. The resulting COF membrane exhibits an unprecedented combination of high water permeance, superior sieving capability, robust mechanical strength, chemical robustness for promising membrane-based separation science and technology.
RESUMEN
Among the various types of materials with intrinsic porosity, porous organic cages (POCs) are distinctive as discrete molecules that possess intrinsic cavities and extrinsic channels capable of facilitating molecular sieving. However, the fabrication of POC membranes remains highly challenging due to the weak noncovalent intermolecular interactions and most reported POCs are powders. In this study, we constructed crystalline free-standing porous organic cage membranes by fortifying intermolecular interactions through the induction of intramolecular hydrogen bonds, which was confirmed by single-crystal X-ray analysis. To elucidate the driving forces behind, a series of terephthaldehyde building blocks containing different substitutions were reacted with flexible triamine under different conditions via interfacial polymerization (IP). Furthermore, density functional theory (DFT) calculations suggest that intramolecular hydrogen bonding can significantly boost the intermolecular interactions. The resulting membranes exhibited fast solvent permeance and high rejection of dyes not only in water, but also in organic solvents. In addition, the membrane demonstrated excellent performance in precise molecular sieving in organic solvents. This work opens an avenue to designing and fabricating free-standing membranes composed of porous organic materials for efficient molecular sieving.
RESUMEN
Traditional piperazine-based polyamide membranes usually suffer from the intrinsic trade-off relationship between selectivity and permeance. The development of macrocycle membranes with customized nanoscale pores is expected to address this challenge. Herein, we introduce 1,4-diazacyclohexane (2N), 1,4,7-triazacyclononane (3N), and 1,4,8,11-tetraazacyclotetradecane (4N) as molecular building blocks to construct the nanoarchitectonics of polyamide membranes prepared from interfacial polymerization (IP). The permeance of covalent organic network membranes follows the trend of 4N-TMC > 3N-TMC > 2N-TMC, while the molecular weight cutoff (MWCO) also follows the same trend of 4N-TMC > 3N-TMC > 2N-TMC, according to their nanopore size of the membranes. The microporosity, orientation, and surface chemistry of covalent organic network membranes can be rationally designed by macrocycle building units. The ordered nanoarchitectonics allows the membranes to attain an excellent performance in graded molecular sieving. Importantly, the novel covalent organic network membranes with tunable nanoarchitectonics prepared from macrocycle building units exhibited high water permeance (32.5 LMH/bar) and retained long-term stability after 100 h of test and bovine serum albumin fouling. These results reveal the enormous potential of 3N-TMC and 4N-TMC membranes in saline textile wastewater treatments and precise molecular sieving.