There is currently great interest in enzyme immobilization to enhance enzyme stability and reusability, and to aid in separation from the reaction mixture, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] but immobilized enzymes on commonly used inorganic and organic solid supports show low activities. This is a result of the leaching of the enzymes from the solid supports and the limited conformational transitions available to the enzymes for chemical interaction on the supports. [1][2][3][4] Enzymes encapsulated by a sol-gel/polymer [3][4][5][6][7][8][9][10] show good activity, but the wide pore-size distribution in sol-gel/polymers cannot be well controlled, and this adversely influences the diffusion of reactants and products during biocatalysis to the detriment of their practical application. [3,4,16] Recently, a number of successful examples of good enzyme activity resulting from enzyme immobilization in uniform mesopores of ordered mesostructured materials have been reported. [14][15][16][17] However, enzyme immobilization in mesopores is limited by the pore size of the mesostructured materials, so that bulky enzymes or enzyme aggregates larger than the mesopores cannot be immobilized. A general and facile approach for the encapsulation of enzymes of various sizes in ordered mesoporous silica is reported here, where the enzymes are entrapped in macroporous cages connected by uniform mesoporous channels. These encapsulated enzymes show good activity, long-term stability, and excellent recycling characteristics. The concept of "fish-in-net" encapsulation of enzymes in ordered mesoporous silica under mild conditions is illustrated in Figure 1. Tetraethylorthosilicate (TEOS) was first assembled from a triblock ethylene oxide (EO)/propylene oxide (PO) copolymer surfactant ( EO 20 PO 70 EO 20 , P123) in ethanol. After evaporation of the ethanol and addition of glycerol, preformed precursors with ordered mesostructured silica particles were obtained in the glycerol solution, which is a non-denaturing solvent for enzymes. The preformed precursors were mixed with the enzyme solution under stirring at 4°C. During the interaction between the enzymes and the preformed precursors, active enzymes (acting as the "fish") were gradually entrapped in the "net" formed by the polymerization and condensation of the ordered mesostructured silica particles. After removal of the glycerol and water by evacuation, the xerogels with encapsulated enzymes were washed with ethanol and water several times to remove polymer surfactants in the mesopores. In contrast to the "ship-in-a-bottle" technique, [18] the enzymes in this work were used as templates for the

With the aim of highlighting the potential talent of the unique singlebenzene skeleton versus the common large π-systems, we propose a general strategy to construct single-benzene fluorophores 1−9, featuring fascinating emission properties in the solid state, for example, high fluorescence quantum yields and wide variety of emission colors. Our molecular design is X-shaped tetrasubstituted benzene of which two electron-donating groups (EDGs) and two electronwithdrawing groups are arranged in an X-shaped fashion. This molecular design enables a very small single-benzene skeleton to show intense fluorescence in the solid state because the π−π stacking and dipole−dipole interaction are inherently avoided in the crystal. More importantly, by simply changing the EDGs, the emission colors in the solid state of these single-benzene fluorophores can be continuously tuned from deep blue to red. In addition, the potential applications of these single-benzene fluorophores as crystal lasing media have been demonstrated by an amplified spontaneous emission measurement.

A novel approach involving the preparation of mannose-bearing chitosan microspheres with entrapping complexes of HBV DNA and PEI was developed to improve the delivery of DNA into antigen-presenting cells (APCs) after intramuscular (i.m.) injection. Compared with the traditional chitosan microspheres, the microspheres could quickly release intact and penetrative PEI/DNA complexes. What's more, chitosan was modified with mannose to target the primary APCs such as dendritic cells (DCs) owing to the high density of mannose receptors expressing on the surface of immature DCs. After i.m. immunization, the microspheres induced significantly enhanced serum antibody and cytotoxic T lymphocyte (CTL) responses in comparison to naked DNA.

In this work, the quantitative relationship in the heredity of β-phase from a solution to a thin film based on poly(9,9-dioctylfluorene) (PFO), the mechanism of β-phase formation, and the effects of β-phase contents on hole mobility were investigated. The heredity based on PFO β-phase from the solution to the thin film was characterized through UV−vis absorption. Results indicated that β-phase can be completely transferred from solutions to films during drying to form films. PFO β-phase was stable and could manage the dynamic changes from a liquid state to a thin-film state. The β-phase content was higher in the diluted solutions, and the reason was revealed through dynamic light scattering. Thus, a new structure model was constructed, and polymer chain aggregation was rendered unnecessary during PFO β-phase formation. The energy status of the β-phase was lower than that of the α-phase. Consequently, PFO chains were autonomously assembled to become orderly. The chemical environment of the low-concentration solution was more suitable than that of the high-concentration solution. The polymer chains in the former could more freely adapt to a flat geometry than those in the latter to facilitate interchain stacking. Chain aggregation was then observed through transmission electron microscopy. Photoinduced charge extraction with a linear increase in voltage was also performed to examine the charge density and hole mobility of PFO. Hole mobility could be enhanced by an order of magnitude when β-phase was increased from 0% to 5.4%. Thus, the presence of a small amount of ordered domains that can form interconnected channels could strongly enhance the carrier transport of materials in poorly ordered organic thin films, such as PFO. This condition is possibly beneficial for photoelectronic devices, and the adaptive nature of PFO chains in solutions to form a flat geometry is the main factor that promotes the order of the system.

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The passivation effect of inorganic perovskite quantum dots (PQDs) is a promising method to attain outstanding performance in perovskite solar cells (PSCs), which has ignited widespread interest recently. Lanthanides (Ln) doped PQDs demonstrate unique properties, but nevertheless, are not explored in PSCs. In this work, four kinds of Ln3+ doped CsPbBrCl2 PQDs (Ln3+ = Yb3+, Ce3+, Eu3+, Sm3+) are firstly introduced into PSCs, which displays the synergistic effect of composition engineering and defect engineering. The results indicate that the introduction of CsPbBrCl2: Ln3+ can not only improve the crystallinity and passivate the intrinsic and surface defects of the MAPbI3 layer through ion and ligand passivation, but also form a stronger LnI bond than PbI, adjust work function (WF), and optimize band alignments. CsPbBrCl2:Sm3+ PQDs possess the best performance and exhibit remarkable promotions of open‐circuit voltage (Voc) from 1.13 to 1.20 V and power conversion efficiency from 18.54% to 22.52%. The humid‐resist, thermal‐resist abilities, and the long‐term stability of PSCs are energetically improved due to enhanced structure stability by Sm3+ doping and the hydrophobic characteristic. The strategy of Ln3+ doped PQDs applied to PSCs provide an approach to achieve high‐performance PSCs.

Operation of temperature sensors over extended temperature ranges, and particularly in extreme conditions, poses challenges with both the mechanical integrity of the sensing material and the operational range of the sensor. With an emissive bendable organic crystalline material, here we propose that organic crystals can be used as mechanically robust and compliant fluorescence-based thermal sensors with wide range of temperature coverage and complete retention of mechanical elasticity. The exemplary material described remains elastically bendable and shows highly linear correlation with the emission wavelength and intensity between 77 K to 277 K, while it also transduces its own fluorescence in active waveguiding mode. This universal new approach expands the materials available for optical thermal sensing to a vast number of organic crystals as a new class of engineering materials and opens opportunities for the design of lightweight, organic fluorescence-based thermal sensors that can operate under extreme temperature conditions such as are the ones that will be encountered in future space exploration missions.

No abstract