Perspective of energy transfer from light energy into biological energy

Energy has always been the most concerned topic in the world due to the large consumption. Various types of energy have been exploited and developed to enhance the output amount so that high requirements can be met. Like the hydro-energy, wind energy, and tidal energy, light energy as a renewable, clean, and widespread energy can be easily harvested. In microcosmic scale, some specific proteins and enzymes in green plants and bacteria play an important role in light harvest and energy conversion via photosynthesis. Inspired by the biomimetic sparks,these bioactive macromolecules and some artificially synthetic unites have been integrated together to improve the light-harvesting, and enhance their utilization efficiency. In this feature article, we primarily discuss that how to create the bio-inorganic hybrid energy converted system via biomimetic assembly strategy and artificially achieve the transformation from light into bioenergy, meanwhile highlight some promising works.

Selective Construction of Borromean Rings and Tweezer-Like Molecular Assembly Featuring Cp^(*)Rh/Ir Clips for Near-Infrared Photothermal Conversion

Making full use of coordination-driven self-assembly strategy,we herein described the selective synthesis of a molecular Borromean rings and two cases of “U”-shaped tweezer-like molecular assemblies in high yield by using bipyridyl ligands based on biphenyl unit and half-sandwich binuclear rhodium(III)/iridium(III) building blocks.The selective synthesis was realized by adjusting the length of dipyridyl arms.The utilization of curved U-shaped bipyridyl ligand L1 led to tweezer-like molecular assemblies.Subsequently,olefinic bonds were introduced to elongate dipyridyl arms obtaining ligand L2.The ligand L2 has two stable conformations,U-shape and Z-shape,which facilitated the formation of different topologies including the tetranuclear macrocycle and Borromean rings with different building blocks in this work.These structures in solid and solution all have been further confirmed by single-crystal X-ray diffraction,NMR analysis,and mass spectrometry.In addition,as an important driving force,π-π stacking interactions not only played a significant role in the stability of structures but also further triggered photothermal conversion in solution.The experimental results demonstrated that compounds 1a and 2 had good NIR photothermal conversion efficiency (11.83% and 17.76%),and further analysis found the photothermal conversion efficiency had a gradual increase in the trend with the π-π stacking interactions increasing.This research expands the application of topological structures in materials science and provides a new idea for the synthesis of novel photothermal conversion materials.

Templated freezing assembly precisely regulates molecular assembly for free-standing centimeter-scale microtextured nanofilms

Nature provides diverse models for manufacturing complex and hierarchical materials by controlling molecular assembly at scales ranging from sub-nano to macroscale. However, developing artificial strategies for manufacturing hierarchical materials with comparable machining capabilities to nature is extremely challenging. Here, a templated freezing assembly strategy is reported, enabling simultaneously regulating molecular assembly spatiotemporally to obtain hierarchical materials with structure control from sub-nano to macroscale. In this way, unique centimeter-scale freestanding nanofilms are assembled from diverse molecules, e.g., proteins and conjugated polymers. A generated silk fibroin(SF) nanofilm presents a tunable β-sheet fraction from 5% to 47%, fiber width from 30 to 3,000 nm, and micro-textures with desired shapes. Such a strategy will lay the foundation for customizing hierarchical functional materials from single or multi-component molecules, e.g., desired bioscaffolds with controlled cell adhesion.

The rational design of multiple molecular module-based assemblies for simultaneously improving rice yield and grain quality

Rice is one of the most important staple food for over half of the world＇s population,and a substantial increase in productivity and quality of rice grain will be required to feed a growing human population.Grain size and shape are the two important components contributing to grain yield and quality,because they impact both yield potential and end-use quality.

Molecular assembly of recombinant chicken type II collagen in the yeast Pichia pastoris

Effective treatment of rheumatoid arthritis can be mediated by native chicken type II collagen(n CCII), recombinant peptide containing n CCII tolerogenic epitopes(CTEs), or a therapeutic DNA vaccine encoding the full-length CCOL2 A1 c DNA. As recombinant CCII(r CCII) might avoid potential pathogenic virus contamination during n CCII preparation or chromosomal integration and oncogene activation associated with DNA vaccines, here we evaluated the importance of propeptide and telopeptide domains on r CCII triple helix molecular assembly. We constructed p C-and p N-procollagen(without N-or Cpropeptides, respectively) as well as CTEs located in the triple helical domain lacking both propeptides and telopeptides, and expressed these in yeast Pichia pastoris host strain GS115(his4, Mut+) simultaneously with recombinant chicken prolyl-4-hydroxylase α and β subunits. Both p C-and p N-procollagen monomers accumulated inside P. pastoris cells, whereas CTE was assembled into homotrimers with stable conformation and secreted into the supernatants, suggesting that the large molecular weight p C-or p N-procollagens were retained within the endoplasmic reticulum whereas the smaller CTEs proceeded through the secretory pathway. Furthermore, resulting recombinant chicken type II collagen p Cα1(II) can induce collagen-induced arthritis(CIA) rat model, which seems to be as effective as the current standard n CCII. Notably, protease digestion assays showed that r CCII could assemble in the absence of C-and N-propeptides or telopeptides. These findings provide new insights into the minimal structural requirements for r CCII expression and folding.

Comparative studies on molecular induced aggregation of hepta-imidazoliumyl-β-cyclodextrin towards anionic surfactants

A β cyclodextrin derivative bearing seven cationic arms and its singly charged analogue, i.e., per-6- deoxy-f-（1-methylimidazol-3-ium-3-yl）-β-cyclodextrin （3） and mono-fi-deoxy-6-（1-methylimidazol- 3-ium-3-yl）-β-cyclodextrin （4） were synthesized and fully characterized. Their induced aggregation behaviours towards two anionic surfactant, that is, sodium dodecyl sulfonate （SDS） and dioctyl sodium sulfosuccinate （Aerosol OT, AOT）, were investigated by UV-vis, NMR, Zeta-potential, dynamic light scattering （DLS）, and transmission electron microscopy. The results revealed that host 3 can induce the molecular aggregation of anionic surfactant at concentration far lower than its original CAC, leading to the larger diameter, the narrower size distribution and the higher thermal stability of the induced aggregate towards the anionic surfactant possessing more hydrophobic tails.

Molecular mechanism of crystal nucleation from solution

Nucleation from solution is fundamental to many natural and industrial processes.The understanding of molecular mechanism of nucleation from solution is conducive to predict crystal structure,control polymorph and design desired crystal materials.In this review,the nucleation theories,including classical nucleation theory(CNT),nonclassical nucleation theory,as well as other new proposed theories,were reprised,and the molecular mechanism of these theories was compared.Then,the molecular process of nucleation,including the current study techniques,the effect of molecular self-assembly in solutions,desolvation process,as well as the properties of solvent and crystal structure on nucleation from solution were summarized.Furthermore,the relationship of molecular conformation in solution and in crystal,and the effect of solute molecular flexibility on nucleation were discussed.Finally,the current challenges and future scopes of crystal nucleation from solution were discussed.

Probing the kinetics in supramolecular chemistry and molecular assembly by microfluidic-NMR spectroscopy

Microfluidic-NMR spectroscopy has been extended to study the kinetics in supramolecular chemistry and molecular assembly.Kinetics of a multicomponent host-guest supramolecular system containing viologen derivatives, β-cyclodextrins and cucurbit[7]urils are studied by a PMMA based microfluidic chip combined with a dedicated transmission line probe for NMR detection.By combining microfluidic technology with NMR spectroscopy, the amount of material required for a full kinetic study could be minimized. This is crucial in supramolecular chemistry, which often involves highly sophisticated and synthetically costly building blocks. The small size of the microfluidic structure is crucial in bringing the time scale for kinetic monitoring down to seconds. At the same time, the transmission line NMR probe provides sufficient sensitivity to work at low(2 m M) concentrations.

Assembly of face-rotating molecular polyhedra

Supported by the National Natural Science Foundation of China,the research team led by Dr.Cao Xiaoyu(曹晓宇)at the State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering,Collaborative Innovation Centre of Chemistry for Energy Materials,Xiamen University,assembled a new series of molecular polyhedra,the face-rotating polyhedra(FRP).This

Assembled Photosensitizers Applied for Enhanced Photodynamic Therapy

Photodynamic therapy(PDT)has emerged as an efficient method for cancer therapy.However,traditional photosensitizers(PSs)always have low bioavailability.For example,hydrophobic PSs tend to aggregate in cells and lead to aggregation-induced quenching;while hydrophilic PSs that have good solubility in water systems can hardly penetrate into cells whose membranes are lipophilic.To overcome these drawbacks,suitable PSs that meet the requirements of PDT are needed.Numerous investigations have been introduced,especially the molecular-assembly technique that can increase the bioavailability of PSs during the tumor therapy process.Besides,increasing the quantum yield of reactive oxygen species(ROS)by adjusting the PS triplet state lifetime as well as developing aggregation-induced emission(AIE)agents can also improve the PDT effect.This review summarizes the molecular-assembly technique to obtain intelligent PSs to achieve high PDT efficiency.First,increasing the quantum yield of ROS by decreasing the energy gap between S_(1)and T_(1)states or increasing the spin–orbit coupling Hamiltonian are introduced.Second,we present the bioavailability of traditional PSs by improving the amphiphilicity of the PSs or using intelligent nanostructures.Then,the AIE PSs that can form ROS in the aggregated state under irradiation are described.Finally,the perspective and challenges of PDT are discussed.

Atom-economic macrocyclic amphiphile based on guanidinium-functionalized selenacrown ether acting as redox-responsive nanozyme

Control of self-assembly is significant to the preparation of supramolecular materials, but the control of hydration, responsiveness, dimension, catalysis of macrocyclic amphiphiles in an atom-economic manner is still a great challenge. The herein presented 527 Da low-molecular-weight macrocyclic amphiphile was fabricated by utilizing the selenium-containing crown ether as a hydrophobic motif together with guanidinium group as the hydrophilic moiety. The resulting benzo[21]crown-7 based macrocyclic amphiphile readily forms a redox-responsive solid nanoparticles in water, which can further interconnect into wrinkled pattern on-surface, as well as exhibits as a nanozyme for catalyzing disulfid bond formation. The present work highlights the great potential of guanidinium-and selenium-containing crown ethers for the control of functional assemblies.

Electron Transport through Hydrogen Bonded Single-Molecule Junctions

Hydrogen bonding is a vital driving force for organizing the hierarchy of molecular structure,especially in biologic field.Due to its directionality,selectivity and moderate strength,hydrogen bonding has been extensively introduced into the molecular recognition,sensing and electronic devices.Electric measurements at single-molecule level facilitate the investigation of hydrogen bonds and provide a comprehensive understanding of the electron transport properties governed by the hydrogen bonding,which is essential for the development of self-assembled electronic systems.This review provides a detailed overview of recent advancements in constructing single-molecule junctions utilizing intramolecular and intermolecular hydrogen bonding.We first introduce the methods utilized for characterizing the electric and dynamic properties of non-covalent interactions.Next,we discuss the mechanisms of electron transport,relevant influencing factors,and typical applications utilizing electrical signals based on single-molecule junctions.Finally,we propose our perspective on the existing challenges and prospective opportunities in utilizing hydrogen bonding for electronic device applications.

Enhanced Bioenergy Transformation by Metal-Free Electrozyme-Based Mitochondrion Nanoarchitectonics

Herein,we couple a synthetic electrozyme in a supramolecule-assembled nanoarchitecture to achieve enhanced bioenergy transformation by mimicking mitochondrial oxidative phosphorylation.Different from the natural counterpart,the metal-free electrozyme is a semiconducting polymer deposited on an electrode.The wellmatched electrocatalytic property of the electrozyme permits oxidization of reduced nicotinamide adenine dinucleotide(NADH)to release protons under a much lower electric potential.As a consequence,the generated proton gradient drives rotary catalysis of adenosine 5′-triphosphate(ATP)synthase reconstituted in a lipid membrane to produce ATP.Remarkably,electrochemical bioenergy conversion of NADH to ATP is accomplished with much higher efficiency in such a bio-like system compared with the natural mitochondria.This work integrates synthetic and natural catalytic chemistry to facilitate enhanced bioenergy transformation,thereby greatly improving prospects in ATP-fueled bioapplications.

Catalase-Conjugated Rose Bengal Biological Nanoparticles with Mitochondrial Selectivity Toward Photodynamic Therapy

Photodynamic therapy(PDT)has emerged as an efficient treatment for cancers in recent years.However,PDT is limited by low utilization of photosensitizers and tumor hypoxia.The short lifetime and diffusion radius of singlet oxygen(^(1)O_(2))further decrease the anticancer effect of PDT.Herein,we design and synthesize diameter-controllable photosensitizer nanoparticles(NPs)which can specifically accumulate on the mitochondria of cancer cells and increase the O_(2) concentrations nearby to enhance PDT efficacy.Catalase(CAT)molecules are initially conjugated with rose bengal(RB)via amide bonds and then self-assembled into CAT-RB NPs.The NPs show excellent enzyme activity in catalyzing the decomposition of hydrogen peroxide into O_(2),which makes the yield of 1O21.65-fold higher than that of free RB.The intracellular uptake efficiency of NPs is increased by up to 150 times compared with pure RB.After endocytosis,the NPs mainly located at mitochondria and ^(1)O_(2) can directly destroy mitochondria under irradiation,thereby greatly decreasing the production of adenosine triphosphate and further leading to the apoptosis of cancer cells.Moreover,CAT-RB NPs can accumulate in tumors and show excellent PDT effects in vivo.This work opens a unique path to break through the current limitations of PDT in cancer treatment.

A Biomimetic Tooth Replicate That Is Hard,Damage-Tolerant,and Self-Healable

Hard materials typically lack the mechanism of energy dissipation and cannot self-heal.Nature addresses this challenge by creating multiscale interfaces between high-contrast materials,namely minerals and biopolymers.Inspired by the enamel-dentin junction in nature,an enamel-like crown consisting ofβFeOOH nanocolumns is interdigitated with a flexible self-healing layer.The iron oxide top layer has exceptionally high modulus and hardness,which is more resistant to cyclic deformation than the bottom layer.The latter however provides an additional pathway for viscous and plastic energy dissipation and enables self-healing by allowing upward polymer diffusion to seal the damage.Picture-frame crack patterns were observed under large loading conditions using microindentation,which localizes the damage at the indentation site.The bending properties can be optimized by varying the thickness of the bottom layer,and the crack induced by bending can be effectively captured at the interface without any delamination.The biomimetic tooth replicate is highly adhesive to a ceramic surface and shows an obvious inhibition effect against Streptococcus mutans,a significant contributor to tooth decay.Combined with ultralow thermal diffusivity,this has great potential as dental material.Learning from nature,our work thus provides a powerful pathway to broadening the scope of synthetic materials for dental replicates.

Si-doping bone composite based on protein template- mediated assembly for enhancing bone regeneration

Bio-inspired hybrid materials that contain organic and inorganic networks interpenetration at the molecular level have been a particular focus of interest on designing novel nanoscale composites. Here we firstly synthesized a series of hybrid bone composites, silicon-hydroxyapatites/silk fibroin/collagen, based on a specific molecular assembled strategy. Results of material characterization confirmed that silicate had been successfully doped into nano-hydroxyapatite lattice. In vitro evaluation at the cellular level clearly showed that these Si-doped composites were capable of promoting the adhesion and proliferation of rat mesenchymal stem cells （rMSCs）, extremely enhancing osteoblastic differentiation of rMSCs compared with silicon-free composite. More interestingly, we found there was a critical point of silicon content in the composition on regulating multiple cell behaviors. In vivo animal evaluation further demonstrated that Si-doped composites enabled to significantly improve the repair of cranial bone defect. Consequently, our current work not only suggests fabricating a potential bone repair materials by integrating element-doping and molecular assembled strategy in one system, but also paves a new way for constructing multi-functional composite materials in the future.

Subtle Side Chain Triggers Unexpected Two-Channel Charge Transport Property Enabling 80%Fill Factors and Efficient Thick-Film Organic Photovoltaics

To clearly show how important the impact of side chains on organic solar cells(OSCs)is,we designed three acceptors IDIC-CxPh(x=4,5,or 6)via subtle side-chain regulation.Despite this small change,significant distinctions were detected.IDIC-C4Ph devices achieve an optimal efficiency of 13.94%under thermal annealing,but thermal-assistant solvent-vapor annealing hugely suppresses the efficiencies to 10%.However,the C6Ph side chain endows extremely disordered stacking orientations,generating moderate efficiencies of~12.50%.Excitingly,the IDIC-C5Ph affords an unexpected two-channel p-p charge transport(TCCT)property,boosting the fill factor(FF)by up to 80.02%and efficiency to 14.56%,ranking the best among five-ring fused-ladder-type acceptors.Impressively,the special TCCT behavior of IDIC-C5Ph enables 470 nm thick-film OSC with a high FF of up to 70.12%and efficiency of 13.01%,demonstrating the great promise in fabricating largescale OSCs.