Membrane channels span the cellular lipid bilayers to transport ions and molecules into cells with sophisticated properties including high efficiency and selectivity. It is of particular biological importance in developing biomimetic transmembrane channels with unique functions by means of chemically synthetic strategies. An artificial unimolecular transmembrane channel using pore‐containing helical macromolecules is reported. The self‐folding, shape‐persistent, pore‐containing helical macromolecules are able to span the lipid bilayer, and thus result in extraordinary channel stability and high transporting efficiency for protons and cations. The lifetime of this artificial unimolecular channel in the lipid bilayer membrane is impressively long, rivaling those of natural protein channels. Natural channel mimics designed by helically folded polymeric scaffolds will display robust and versatile transport‐related properties at single‐molecule level.

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Potassium ion channels specifically transport K ions over Na ions across a cell membrane. A queue of four binding sites in the K channel pore plays significant roles during highly selective conduction. A kind of aromatic helical oligomer was synthesized that can selectively bind K over Na . By aromatic stacking of helical oligomers, a type of artificial K channels with contiguous K binding sites was constructed. Such artificial channels exhibited exceptionally high K /Na selectivity ratios during transmembrane ion conduction.

Using biological materials for light-harvesting applications has attracted considerable attention in recent years. Such materials provide excellent environmental compatibility and often exhibit superior properties over synthetic materials. Herein, inspired by the outstanding energy transfer performance in coelenterates, we constructed a template-free, highly ordered two-dimensional light-harvesting system by covalent-induced coassembly of EBFP2 (donor) and EGFP (acceptor), in which the fluorescent chromophores were well distributed and adopted a fixed orientation. By introducing approximate square planar binding sites on the side surface of protein, assembly pattern was pin down and self-assembly extended in orthogonal directions to achieve monolayered and tessellated protein nanoarrays. The excellent antiself-quenching property of fluorescent proteins endowed the coassembled system with attractive light-harvesting capability. Even at high local concentrations, a low resonance energy transfer self-quenching was observed and, therefore, energy can be efficiently transferred. More importantly, the distance between adjacent chromophores is continuously adjustable. By making minor changes to the length of the inducing linker, we have achieved significant control over the size of the assembly. A micron-sized light-harvesting system with satisfactory energy transfer efficiency was finally obtained. This work developed a template-free light-harvesting system completely based on fluorescent proteins (FPs), which overcame the restriction of using templates. Not limited to this work, the special core−shell structure of FPs may be expected to direct the optimization of fluorescent dyes by cladding.

Semithiobambus[6]uril is shown to be an efficient transmembrane anion transporter. Although all bambusuril analogs (having either O, S or N atoms in their portals) are excellent anion binders, only the sulfur analog is also an effective anion transporter capable of polarizing lipid membranes through selective anion uniport. This notable divergence reflects significant differences in the lipophilic character of the bambusuril analogs.

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(2015) Linear-dendrimer type methoxy-poly (ethylene glycol)-b-poly (ɛ-caprolactone) copolymer micelles for the delivery of curcumin, Drug Delivery, 22:1, 58-68, DOI: 10.3109/10717544.2014 Methods: A novel linear-dendrimer methoxy-poly (ethylene glycol)-b-poly ("-caprolactone) copolymer was synthesized through O-alkylation, basic hydrolysis and ring-opening polymerization reaction with methoxy-poly (ethylene glycol), epichlorohydrin and "-caprolactone as raw materials. Its structure was characterized by 1 H-NMR and GPC. The copolymer's hemolysis and micellar encapsulation for curcumin by thin-film hydration were studied. Curcumin-loaded micelles were evaluated by use of in vitro release, FT-IR and X-ray diffraction. Curcumin-loaded micelles' in vitro cytotoxic activities against Hela and HT-29 cells were done, and its pharmacokinetic parameters were also carried out. Results: Curcumin was encapsulated into the micelles with 92.54% of entrapment efficiency and 12.84% of drug loading in amorphous forms. The dissolubility of nanoparticulate curcumin was 1.70 Â 10 5 times higher than that of curcumin in water. The obtained copolymer showed no hemolysis. In vitro drug release study indicated that, in all cases, the kinetics was adjusted well to the Makoid-Banakar model (R 2 abj ¼ 0.9984). In addition, data were analyzed by the Korsmeyer-Peppas model, n values were 0.43, indicating that the drug release was accomplished by the combination diffusion and polymer chain relaxation. The cytotoxicity experiment indicated that the nanoparticulate curcumin kept up its potent anti-cancer activities. The pharmacokinetic results showed that the MRT 0-1 , t 1/2z and AUC 0-1 of Curcuminloaded micelles were 1.64, 6.54 and 4.67 times higher than that of CUR control solution. Conclusions: The copolymeric micelles loading curcumin might act as a delivery vehicle for CUR.

The current state‐of‐the‐art of satellite gravity data processing makes use of de‐aliasing products to reduce high‐frequency mass anomalies. For example, the most recent official Atmosphere and Ocean De‐aliasing products (AOD1B‐RL06) are applied for the Gravity Recovery and Climate Experiment (GRACE) and GRACE‐Follow On (GRACE‐FO) missions. The temporal resolution of AOD1B‐RL06 is 3 h, and spectrally, they are computed up to degree and order 180. In this study, we explore a refined, e.g., geometrically, physically, and numerically improved, mass integration approach that is important for computing the atmosphere part of these products. Besides, the newly available ERA5 climate data are used to produce a new set of non‐tidal atmosphere de‐aliasing product (HUST‐ERA5) that is computed hourly up to degree and order 100, covering 2002 onwards. Despite an overall agreement with AOD1B‐RL06 (correlation≥0.99), considerable discrepancies still exist between HUST‐ERA5 and AOD1B‐RL06. The possible reasons are therefore analyzed, and we find the input climate data, sampling rate and integration method may result in a product difference of ∼0.3, ∼0.15 and ∼0.05 millimeter geoid height, respectively. The total differences between HUST‐ERA5 and AOD1B‐RL06 can lead to a mean variation of ∼7.34 nm00/s on the laser ranging interferometry (LRI) range‐rate residuals, for example, during January 2019, which is already close to the LRI precision. This impact is invisible for the GRACE (‐FO) gravity inversion because of the less accurate on‐board KBR (K‐band ranging) instrument, however, it will be non‐negligible and should be considered when the LRI completely replaces the KBR in the future gravity missions.