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To understand the relationships between channel size and ion selectivity, we have developed a new type of artificial ion channel based on pore-forming helical polymers consisting of phenanthroline-...

The profitability of electric heating projects in Northern China is poor. A kind of combined market-oriented trading strategy to improve the economy of electric heating projects is put forward. The price game model for direct power purchase, compensation model for carbon emission reduction benefits and load aggregation revenue model are constructed, and the optimal proportion of clean energy and conventional energy consumed under the condition of ensuring heating reliability is analyzed. An electric heating project was analyzed as an example, the results showed that in the direct power purchase transaction, the power price is 0.2125 RMB/kWh, which is 0.0591 RMB/kWh lower than the catalogue tariff. Revenue from carbon trading and auxiliary service transaction is 469,913.87 RMB and 289,218.09 RMB, respectively, which is equivalent to reducing electricity cost of 0.0253 RMB/kWh and 0.0156 RMB/kWh, respectively. The ultimate power cost is 0.1716RMB/kWh, which is 0.1 RMB/kWh lower than the current catalogue tariff. Besides, the more clean energy an electric heating project consumes, the better its economy will be, and in this example, the best proportion of clean energy and conventional energy is 80% and 20%. The research results could help to promote the sustainable development of clean heating in northern China.

Lithium ions have been applied in the clinic in the treatment of psychiatric disorders. In this work, we report artificial supramolecular lithium channels composed of pore-containing small aromatic molecules. By adjusting the lumen size and coordination numbers, we found that one of the supramolecular channels developed shows unprecedented transmembrane transport of exogenous lithium ions with a Li

In this contribution, we report the synthesis of an imine-based soft 2D covalent organic framework (S-COF) with compacted honeycomb topology via inveterately selecting a helically folded ditopic flexible linker and a trigonal building block. In contrast to various topological structures of rigid monomer-based COFs (R-COFs) reported so far, owing to the presence of flexible skeleton S-COF can spontaneously form a compacted and nonporous topological structure via intramolecular π stacking of presupposed honeycomb-like topology. Such S-COFs with a compacted honeycomb topology have neither been proposed theoretically nor been achieved experimentally. The compacted topological structure of 2D S-COF was clearly characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), and circular dichroism (CD) measurements. This study opens a new window to the development of S-COFs and will significantly expand the scope of COF materials.

Anion transmembrane nanochannels constructed from dynamic covalent helices (DCHs) are reported. The dynamic covalent structures can be synthesized by one-pot dynamic covalent reactions and helically self-fold into nanotubes through intramolecular hydrogen bonding and π-π interactions. Such helical structures can vertically self-assemble into long nanofibers under π-π stacking and their hollow nanocavities finally form ion permeation pathways across the lipid membranes. Single-channel electrophysiology signals provide solid evidence of DCHs following the channel rather than the carrier mechanism. Owing to the pore-forming capacity of DCHs, nanochannels are able to accelerate the movement of anions across lipid membranes with high transport activity (EC50 =0.08 mol %). Moreover, DCH channels show dehydration energy dependent anion selectivity. This report highlights the importance of such DCHs as general channel scaffolds with economical synthesis and special nanocavities.

Understanding of the structure-function relationships of natural protein channels remains a challenging task because of their unattainable physiological functions in terms of selectivity. To achieve this, a synthetic system of chemically modified channels has been constructed based on helical polymer scaffolds. Here, we report a type of positively charged channels in which multiple quaternary ammonium groups are covalently modified on the lumen surface of helical polymer while the helical conformation is intact. Compared to unmodified channels, the existence of multiple charged groups in the cavity not only makes the lumen size narrower but also essentially changes the channel properties without obstructing channel structure. Our study indicates that positively charged channels preferentially transport anions with size-dependent selectivity, whereas alkali metal ions are almost completely suppressed by electrostatic repulsion. As a consequence, a specific artificial channel with high Cl

Glycyrrhiza uralensis (liquorice) is a well-known medicinal plant. Its roots and rhizomes are used as the popular Chinese herbal medicine Gan-Cao. An ethanol extract of the aerial parts of G. uralensis showed antidiabetic effects on db/db mice. It decreased the blood glucose level by 30.3% and increased the serum insulin level by 41.8% compared to the control group. Eighty-six phenolic compounds (1-86) were obtained from the aerial parts, including the new prenylated isoflavanones (1-5), isoflavans (6-9), and a 2-phenylbenzofuran (10). The structures were identified by NMR and HRESIMS data analyses, and the absolute configurations were established by comparing the calculated and experimental ECD spectroscopic data. Compounds 2, 6, and 10 inhibited PTP1B with IC50 values of 5.9, 6.7, and 5.3 μM, respectively. Compound 2 and the known compounds glycycoumarin (76) and glyurallin A (79) inhibited α-glucosidase with IC50 values of 20.1, 0.1, and 0.3 μM, respectively. Compound 4 at 10 μM increased the glucose uptake rate to 95% in an insulin resistance HepG2 cell model (p < 0.01).

Here, a straightforward and rational approach to construct supramolecular assemblies with ordered nanostructures in a two-dimensional arrangement is reported. Taking advantage of the synergistic effect of multiple non-covalent interactions (hydrogen bonding and π–π interactions), the designed molecular monomer has a specific orientation in the self-assembly process, thus realizing two-dimensional control. Supramolecular two-dimensional nanosheets with single-layer thickness and controllable dimensions have been obtained, which can be clearly confirmed using TEM, SEM, AFM and XRD and by comparing with the self-assembled structures of the control system. The strategy of collaborative self-assembly proposed here using multiple non-covalent interactions is expected to be extended to the construction of various kinds of unique supramolecular 2D materials.

Small molecules that independently perform natural channel-like functions show greatly potential in the treatment of human diseases. Taking advantage of aromatic helical scaffolds, we develop a kind of foldamer-based ion channels with lumen size varying from 3.8 to 2.3 A through a sequence substitution strategy. Our results clearly elucidate the importance of channel size in ion transport selectivity in molecular detail, eventually leading to the discoveries of the best artificial K+ channel by far and a rare sodium-preferential channel as well. High K+ selectivity and transport activity together make foldamers promising in therapeutic applications.

Units of ureidopyrimidinone (UPy) which dimerize via strong quadruple hydrogen bonding are widely used for the construction of supramolecular systems. This self-complementary system exists in the tautomerism equilibrium of 4[1H]-pyrimidinone dimer and pyrimidin-4-ol dimer, making generated supramolecular assembly systems essentially complicated. In this contribution, a rational but simple design concept is described for preorganizing the self-complementary quadruple hydrogen bonding of UPy via supramolecular strategy into a single-quadruple DDAA-AADD dimeric array. With this concept, the designed UPy derivatives form only 4[1H]-pyrimidinone dimer with a ketone configuration via intermolecular hydrogen-bonding interactions, both in the solid state as well as in solution, as is evident from single-crystal X-ray diffraction and 1H NMR spectroscopy. The single DDAA-AADD dimeric array provides defined noncovalent driving forces that can be used to generate constitutionally clear supramolecular structures that are vitally important in the fields of supramolecular chemistry and materials.

Herein, we demonstrate a supramolecular nanochannel formed by intermolecular π stacking of pyridine-pyridazine helical oligomers, wherein alkali ions could be easily recognized and transported. Importantly, this nanochannel also revealed reversible collection and triggered-release behaviors via modulating the folded and unfolded states of helical pyridine-pyridazine oligomers.

Self-assembled vesicles are constructed based on supra-amphiphiles formed by cucurbit[8]uril and its two guest molecules. By modifying one of the guest molecules, an artificial nanohydrolase is constructed. An enhancement of catalytic activity for hydrolysis of 4-nitrophenyl acetate is observed, which is attributed to the enrichment effect of substrate around catalytic sites through the molecular recognition.

A type of aromatic helical capsules was synthesized. The crystal structure proved an inner cavity that could perform switchable encapsulation and release of potassium ion through protonation/deprotonation-mediated extension and contraction of molecular motion.

Prenylated pterocarpans are valuable natural products that play significant roles in plant defence and possess diverse biological activities. However, structural diversity of prenylated pterocarpans is still limited. Prenyltransferases (PTs) could catalyze the transfer of prenyl moieties to acceptor molecules and increase the structural diversity and biological activity of natural products. Up to date, only two pterocarpan PTs have been identified from plants. In this study, a new pterocarpan prenyltransferase gene, designated as PcM4DT, was identified from Psoralea corylifolia. The deduced polypeptide is predicted to be a membrane-bound protein with eight transmembrane regions. Functional characterization of recombinant PcM4DT demonstrated this enzyme could catalyze C-4 prenylation of pterocarpans, and exhibited strict substrate specificity to maackiain and 3-hydroxy-9-methoxy-pterocarpan. It also showed a strict donor specificity to DMAPP. Furthermore, removal of the putative transit peptide of PcM4DT obviously increased the catalytic activity (up to 90%). PcM4DT represents the first PT identified from the Psoralea genus.

We reported a type of strong and highly directional non-covalent interactions based on the dimerization of single-stranded helix to double-stranded helix that can achieve supramolecular polymerization, giving rise to the formation of linear supramolecular polymers.

목적: 본 연구는 페룰산의 자체 에멀젼을 위한 최적의 포뮬러 및 제조공정을 연구 하기 위한 것이다. 방법: Pseudo three phase diagram방법을 이용하여 각기 다른 계면활성제의 마이크로 에멀젼 영역의 형성 크기에 대한 영향을 연구하고, 또한 SZ-100나노입 자분석기를 이용하여, 계면활성제, 보조계면활성제, 오일의 최적의 비율을 확인하였다. 마지막으로 SZ-100나노입자분석기 및 Zeta 전위 분석기를 이용하여 마이크로 에멀젼의 안정성을 확인하였다. 결과: Pseudo three phase diagram방법과 SZ-100나노입자분석 기를 이용하여 측정한 결과를 종합하여, 최적의 에멀젼 처방비율은 polyoxyethylene castor oil (Cremophor EL):polyethylene glycol 40 (PEG 40):무수에탄올:isopropyl myristate (IPM)=3.15:3.15:1.8:1 이고, 에멀젼의 평균입자크기는 15.5 nm 이며, 이때 마이크로 에 멀젼 체계 수분함량은 90% 이었다. 페롤산의 최대 약물적재량(maximum drug loading)은 5.2% 이며, 에멀젼의 안정성 또한 우수하 다는 것을 확인하였다. 결론: 위와 같은 에멀젼 처방의 연구는 페롤산과 같은 불용성 물질의 수중에서의 용해도를 대폭 증가시킴으 로써, 실제 생산응용 시에 중요한 가치를 가질 것으로 사료된다

Potassium ion channels specifically transport K+ ions over Na+ ions across the cell membrane. A queue of four binding sites in the K+ channel pore plays significant roles during highly selective conduction. Herein, we synthesized a kind of aromatic helical oligomers 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. We discovered that such artificial channels exhibited exceptionally high K+/Na+ selectivity ratios during transmembrane ion conduction.

수분통로단백질인 aquaporin 3 (AQP3)은 백반증, 건선 등 다양한 피부 관련 질병의 발현에 중요한 역할을 한다. 본 연구에서는 AQP3 가 피부질환에 미치는 영향을 확인함으로써, AQP3의 피부 속 조절 메커니즘 및 피부작용에 대해 연구하고자 한다. 이를 위해 피부에서 AQP3의 전달 및 기능을 요약한 후 향후 화장품 영역에서 AQP3의 새로운 발전 방향을 밝히고자 한다.

Redox responsive vesicles were constructed based on self-assembly of a supra-amphiphile built by the host- guest interaction between β-cyclodextrin and a ferrocene derivative. The structure and destruction-reconstruction reversibility of the “smart” vesicles were clearly characterized by electron microscopy and dynamic light scattering. Notably, these vesicles were proved to be capable of controlled release function and bringing protease resistance to the enzyme, showing great biocompatibility and promising applications.

A kind of light-responsive vesicle was prepared by aqueous self-assembly of α-CD and an azobenzene-containing M-helical foldamer, which displayed dynamic disassembly–reassembly structural transformation when alternately irradiated by UV and visible light. Distinctively, this vesicle also exhibited enantioselective release abilities toward racemic propranolol (a β-blocker), owing to the M-helical building blocks.

The reversible unfolding-refolding transition is considerably important for natural elastomeric proteins (e.g., titin) to fulfill their biological functions. It is of great importance to develop synthetic versions by borrowing their unique stretchable design principles. Herein, we present a novel pulsating vesicle by means of the aqueous self-assembly of supra-amphiphilic helices. Interestingly, this vesicle simultaneously features dynamic swelling and shrinkage movements in response to external proton triggers. Titin-like unfolding-refolding transformation of artificial helices was proved to play a crucial role in this pulsatile motion. Moreover, the vesicular membrane of this vesicle has exhibited tunable permeability during reversible expansion and contraction circulation. Meanwhile, light can also be used as a driving force to further regulate the disassembly-reassembly transformation of the pulsating vesicle. In addition, the drug delivery system was also employed as an investigating model to estimate the permeability variation and disassembly-reassembly behaviors of the pulsating vesicles, which displayed unique dual quick- and sustained-release behaviors toward anti-cancer agents. It is anticipated that this work opens an avenue for fabricating novel stretchable biomimetics by using the exclusive unfolding-refolding nature of artificial foldamers.

Helical supramolecular polymers with a wide lumen structure can puncture the lipid bilayer membrane to facilitate the transport of glucose., The manipulation of strong noncovalent interactions provides a concise and versatile strategy for constructing highly ordered supramolecular structures. By using a shape-persistent building block consisting of phenanthroline derivatives and two quadruply hydrogen-bonding AADD moieties, a type of precise helical supramolecular polymer (HSP) nanotube has been developed. The helical conformation of the supramolecular polymers has been proved via various techniques, showing significantly expanded topologies of supramolecular polymers. From the production of new topological structures of supramolecular polymers, predictable properties and functions have arisen. In this study, the helical folding of supramolecular polymers gave rise to the generation of specific wide lumen structures that can be directly visualized via TEM, and the resulting HSP nanotubes can puncture the lipid bilayer membrane to facilitate the transportation of glucose.

Electric heating can effectively control the winter haze and promote renewable energy accommodation, which has significant environmental and social benefits. However, due to the low investment enthusiasm of heating enterprises, the government provides huge subsidies to maintain the operation of electric heating. Based on this background, the environmental benefits of electric heating projects are quantified, and the economic and environmental benefits of urban wind power central heating projects are analyzed and evaluated from the perspective of the life cycle. Then, taking a wind power central heating project in northern China as an example, a more comprehensive, scientific, and accurate evaluation of the wind power central heating project has been carried out. The results show that the electric heating project has great environmental benefits, but the direct economic benefits are poor, which is mainly caused by its high initial investment and high electricity price. Finally, specific suggestions are put forward for the poor economic efficiency of wind power central heating projects. The research results can provide a reference for further perfecting the transaction mechanism of wind power centralized heating, formulating clean heating development policies, and promoting the development of clean heating in northern China.

Rational redesign of allosteric protein offers an efficient strategy to develop switchable biocatalysts. By combining the computational design and protein engineering, a glutathione peroxidase (GPx)-like active center that contains the catalytic selenocysteine (Sec) residue and substrate-binding Arg residue was precisely incorporated into the allosteric domain of adenylate kinase (AKe). The engineered selenoenzyme shows not only high GPx activity but also adenosine triphosphate (ATP)-responsive catalytic property, which is regulated by its opened to closed conformational change upon ATP binding. Theoretical and mutational analysis reveals that the synergistic effect of electrostatic interactions and van der Waals (vdW) interactions for substrate recognition is a major contribution to the high activity. The mitochondrial oxidative damage experiment further demonstrated its antioxidant ability at the subcellular level, offering a potential application toward controllable catalysis in vivo.

Laterally functionalized pillar[5]arenes were synthesized for the first time by bromination at the methylene bridge of dimethoxypillar[5]arene. The synthesized molecule was then used as a novel building block by being covalently self-assembled into polymer nanocapsules and 2D polymer films.

In this study, a preferential trans configuration with the assistance of the steric hindrance effect was demonstrated in a dynamic covalent reaction between 2-pyridyl hydrazide and 2-pyridyl aldehyde. By employing the dynamic covalent reaction between dihydrazide and dialdehyde, a type of self-folding helical dynamic covalent polymer was created by spontaneous configuration control. The helical polymers possess folding-directed hollow tubular structures and thus are capable of providing a specific microenvironment for catalyzing the thiol-related oxidation reaction in the presence of hydrogen peroxide.

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.

Manipulating proteins to self-assemble into highly ordered nanostructures not only provides insights into the natural protein assembly process but also allows access to advanced biomaterials. Host-guest interactions have been widely used in the construction of artificial protein assemblies in recent years. CB[8] can selectively associate with two tripeptide Phe-Gly-Gly (FGG) tags with an extraordinarily high binding affinity (Kter = 1.5 × 1011 M-2). However, the FGG tags utilized before are all fixed to the N-termini via genetic fusion; this spatial limitation greatly confined the availability of the CB[8]/FGG pair in the construction of more sophisticated protein nanostructures. Here we first designed and synthesized a maleimide-functionalized Phe-Gly-Gly tag as a versatile site-specific protein modification tool; this designed tag can site-selectively introduce desired guest moieties onto protein surfaces for host-guest driven protein assembly. When regulating the self-assembly process of proteins and CB[8], the constructed protein nanosystem can exhibit distinctive morphological diversities ranging from nanorings, nanospirals, nanowires to superwires. This work developed a new strategy for site-specific protein modification of the CB[8] binding tag and provides a possible direction for the construction of 'smart', dynamic self-assembly systems.

The self-assembly of AB diblock copolymer solutions confined in a cylindrical nanopore is investigated systematically via Monte Carlo simulations. Two types of diblock copolymers, i.e. hydrophobic and amphiphilic AB diblock copolymers, are examined to reveal the effects of the wall surface properties, copolymer concentration, and diameter of the cylindrical nanopore on the self-assembled nanostructures. It was found that the wall surface properties and the nanopore diameters dominate the self-assembled nanostructures, whereas the copolymer concentration has little influence on the resulting nanostructures. Moreover, the contact number and mean-square radius of gyration of hydrophobic polymer segments were used to monitor the evolutions of the chain configurations under cylindrical confinement. It is interesting to note that the polymer chains were more folded when the confinement effect (le/d) exceeded a critical value, thus causing a transition in the self-assembled structures. This result indicates that the block copolymer can automatically adjust its chain configuration to adapt to the strongly confined environment, which provides new opportunities to explore more novel self-assembled nanostructures based on existing block copolymers.

In this work, we investigated the self-assembly of helical small molecules and found that the formed micrometer-sized supramolecular structures represented macroscopic chirality. Our observation will provide useful information for exploring the factors which are able to essentially control the chiral expression from molecular details to high-level chirality occurred in nature.

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.

An effective method is reported to synthesize aromatic helical polymer nanochannels by combining both the well-studied aromatic amide helical codons with pyridine-oxadiazole helical codons into helical structure sequences. With this strategy, a type of helical polymer nanochannel that shows structure-directed transmembrane transport functions is synthesized. Although such nanochannels show relatively weak selectivity for the transportation of alkali metal ions, accessible chemical mutation of helical structure sequences will provide a great chance for the design of desired channel property. The straightforward preparation of well-established pyridine-oxadiazole helical structure will significantly promote the synthesis of this kind of aromatic helical polymer nanochannels. With the development of aromatic amide foldamers, moreover, a number of "monomers" will be available for the preparation of helical polymer nanochannels.

Herein, a new reductive-responsive pillar[5]arene-based, single-molecule-layer polymer nanocapsule is constructed for drug delivery. The functionalized system shows good biocompatibility, efficient internalization into targeted cells and obvious triggered release of entrapped drugs in a reducing environment such as cytoplasm. Besides, this smart vehicle loaded with anticancer drug shows excellent inhibition for tumor cell proliferation and exhibits low side effect on normal cells. This work not only demonstrates the development of a new reductive-responsive single molecular layer polymer nanocapsule for anticancer drug targeting delivery but also extends the design of smart materials for biomedical applications.

An anion transporter with a selenoxide group was able to form nanoparticles in water, whose activity was fully turned off due to the aggregation effect. The formed nanoparticles have a uniform size and can be readily dispersed in water at high concentrations. Turn-on of the nanoparticles by reducing molecules is proposed to be a combined process, including the reduction of selenoxide to selenide, disassembly of the nanoparticles and location of the transporter to the lipid membrane. Accordingly, a special acceleration phase can be observed in the turn-on kinetic curves. Since turn-on of the nanoparticles is quantitatively related to the amount of reductant, the nanoparticles can be activated in a step-by-step manner. Due to the sensibility of this system to thiols, cysteine can be detected at low nanomolar concentrations. This ultra-sensitive thiol-responsive transmembrane anion transport system is quite promising in biological applications.

A new family of bipodal anion transporters based on chalcogen-containing scaffolds has been designed and synthesized. Though structurally related to the well-studied tripodal anionophores, these molecules are simpler with only two anion-binding sites. However, the activities remain high. Anion transport could be facilitated by the new transporter at an exceptionally low loading of transporter/lipid ratio of 1:500000. This impressive efficiency is comparable with the most active one from the tren-based tripodal series. To investigate influences from different scaffolds and substituent groups, lipophilicity, anion-binding property, and transport activity of each molecule were studied. It was found that the bridge atom has a major impact on transport activities mainly as a result of anion-binding differences. The results also suggest that chalcogen can act as a key structural modulator to develop highly effective anion transporters and optimize their activities.

The cooperative self-assembly of polystyrene-b-poly(4-vinylpyridine) block copolymers (BCPs) and gold nanoparticles (AuNPs) confined within the emulsion droplets is studied by combining both the experiments and Monte Carlo simulations. The results indicate that the entropic interaction between the AuNPs and BCP domain is a critical parameter to dominate the spatial arrangement of AuNPs and the nanostructure of the hybrid nanoparticles, which can be utilized to design novel hierarchical hybrid nanoparticles. Based on this theoretical observation, a large number of unique Janus hybrid nanoparticles, including pupa-like nanoparticles with AuNPs concentrated at one pole of the particles, spherical nanoparticles with AuNPs enriched in a bulge on the sphere surface, and the gourd-like, clover-like, and four-leaf-clover-like nanoparticles from the further hierarchical assembly of small hybrid Janus nanoparticles, are fabricated via three-dimensional (3D) confined self-assembly.

Light-responsive amphiphilic spiropyrans-decorated polyamidoamine (SP-P3) with ill-defined structure was prepared by using 3.0G-PAMAM as the scaffold and introducing the spiropyrans to the periphery of it randomly. Under visible light illumination, the ill-defined structure SP-P3 could form an adaptive amphiphilic macromolecule by rearranging dynamically the peripheral amino and SP groups on the surface of PAMAM. The resultant adaptive amphiphilic SP-P3 could hierarchically self-assemble into uniform macrorods about 800–1100 nm in width and 50–80 μm in length. When irradiated with UV light (365 nm), hydrophobic SP-P3 would isomerise into hydrophilic MC-P3, and induced the disassembly of rod-like aggregates. Irradiation with visible light transformed the MC-P3 back to the SP-P3 and then it could re-self-assemble into the rod-like aggregates. These results demonstrated that these macrorods could reversibly disassemble and re-self-assemble in aqueous solution under alternative UV and visible light irradiation. Our experiments not only provide a novel strategy for preparing responsive dynamic materials, but also support the concept that ill-defined amphiphilic macromolecules could also self-assemble to form well-shaped supramolecular structures.

A Ca(2+) -responsive artificial selenoenzyme was constructed by computational design and engineering of recoverin with the active center of glutathione peroxidase (GPx). By combining the recognition capacity for the glutathione (GSH) substrate and the steric orientation of the catalytic selenium moiety, the engineered selenium-containing recoverin exhibits high GPx activity for the catalyzed reduction of H2 O2 by glutathione (GSH). Moreover, the engineered selenoenzyme can be switched on/off by Ca(2+) -induced allosterism of the protein recoverin. This artificial selenoenzyme also displays excellent antioxidant ability when it was evaluated using a mitochondrial oxidative damage model, showing great potential for controlled catalysis in biomedical applications.

Smart supramolecular nanoenzymes with temperature-driven switching property have been successfully constructed by the self-assembly of supra-amphiphiles formed by the cyclodextrin-based host-guest chemistry. The self-assembled nanostructures were catalyst-functionalized and thermosensitively-functionalized through conveniently linking the catalytic center of glutathione peroxidase and thermosensitive polymer to the host cyclodextrin molecules.The ON-OFF switches for the peroxidase activity by reversible transformation of nanostructures from tube to sphere have been achieved through changing the temperature. We anticipate that such intelligent enzyme mimics could be developed to use in an antioxidant medicine with controlled catalytic efficiency according to the needs of the human body in the future.

Glutathione peroxidase (GPx) is a vital antioxidant enzyme involved in the reduction of reactive oxygen species and protects cells from oxidative damage. Consequently enormous efforts have been devoted to developing artificial catalysts with GPx function. Besides the research on enhancing the catalytic activity of GPx mimics, the design and construction of smart GPx models has also inspired great interest. Herein, a novel photo-responsive selenium-containing vesicular GPx model was successfully constructed by supramolecular self-assembly of the cationic surfactant PyC10AzoC10Py with benzeneseleninic acid (PhSeO2H) through hydrophobic and electrostatic interactions in aqueous media. This selenium-containing vesicular catalyst showed remarkable GPx-like activity, which is 692 times more effective than PhSeO2H for the reduction of cumene hydroperoxide (CUOOH) by 4-nitrobenzenethiol (NBT). Interestingly, when an equimolar amount of α-CD was added, the GPx-like activity of the catalytic vesicle declines remarkably due to the vesicle disaggregation in the presence of α-CD. Whereas the biomimetic system was irradiated by UV light at 365 nm, the catalytic vesicle was formed again and the GPx-like activity recovered.