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Herein, a nitrogen, carbon co-doped anatase and rutile double-phase waxberry-shaped TiO2composite photocatalyst is prepared with the one-step simple hydrothermal synthesis process, in which P25 was used as the precursor, and urea as the source of nitrogen and carbon. A suitable valence band position (2.52 eV) is provided by N–C–TiO2, with more active species (e.g. h+, e−, •OHand •O2) being formed on the active catalysis surface, which is helpful to the redox reaction. Further comparison of experimental results (Eg= 3.01 eV) proved that the novel N–TiO2has preferable photocatalytic activity. In this study, an ingenious nitrogen- carbon co-doping structure was designed for the improvement of TiO2photocatalytic performance, which is much for reference of this method to other photocatalyst designs.

As a class of electrochemiluminescence (ECL) enhancers, silver-based materials have broad application prospects. In this work, a novel silver metal–organic framework (AgMOF) was developed as a self-enhanced ECL emitter by one-step mixing and standing at room temperature. The AgMOF could produce strong and stable ECL emissions based on a double-amplification method, which originated from the aggregation-induced ECL emission of ligands and catalyzing S2O82–to produce more SO4•–by silver. Moreover, an ECL resonance energy transfer (ECL-RET) biosensor with AgMOF as a donor and BHQ2 as an acceptor was fabricated by duplex-specific nuclease (DSN)-assisted target recycling amplification to detect miRNA-107. The biosensor exhibited a strong ECL-RET effect due to the higher ECL emission of the AgMOF and perfect match of spectra between the AgMOF and BHQ2. Upon the introduction of DSN and target miRNAs, the specific DNA–RNA binding and nuclease cleaving could trigger the detachment of BHQ2, resulting in an increased ECL signal of AgMOF. Benefiting from the ECL-RET and DSN-assisted target recycling amplification methods, this biosensor achieved a wide linear relationship range from 20 to 120 fM with a low limit of detection (4.33 fM). This research presents an effective emitter for self-enhanced ECL systems, which broadens the potential ECL applications of silver-based nanomaterials.

Peroxynitrite (ONOO–), a highly reactive nitrogen species (RNS) generated mainly in mitochondria, has been identified to be associated with numerous pathophysiological processes, and thus accurate ONOO–imaging with superior sensitivity and selectivity is highly desirable. Herein, we prepared a new type of carbon quantum dots (CQDs) with mitochondria-targeting function without the aid of any targeting molecules viaa simple one-step hydrothermal route. The as-prepared CQDs not only displayed relatively uniform size distribution, few surface defects, high photostability, and excellent biocompatibility but also exhibited good selective fluorescence turn-off response toward ONOO–, owing to the oxidation of amino groups on the surface of carbon dots. A great linear correlation between the quenching efficiency and ONOO–concentration in the range from 0.15 to 1.0 μM with a detection limit of 38.9 nM is shown. Moreover, the as-prepared CQDs acting as a functional optical probe through a self-targeting mechanism were successfully applied for in situvisualization of endogenous ONOO–generated in the mitochondria of live cells, providing great promise for elucidating the complex biological roles of ONOO–in related pathological processes.

Regulation of apoptosis represents a key parameter in all living organisms. In this paper, an input-induced logic-gated modular nanocalculator is designed to regulate cancer cell apoptosis by programmatically combining and connecting logic gate modules with different functions. Viarational design of the various logic gate modules of the nanocalculator, different apoptosis related operations including cancer cell targeting, apoptosis induction, and apoptosis monitoring could be performed. Importantly, each of these logic gate modules could independently perform apoptosis related YES logic operations when ran separately. After combining each YES logic gate module into a logic circuit and connecting it to the GO scaffold to construct a logic-gated nanocalculator, the input-induced logic-gated modular nanocalculator could selectively enter cancer cells and control the drug release to logically apoptosis (output), by performing AND logic gate operations when inputs (nucleolin and H+) were included at the same time. Moreover, evidence suggests that these efficient logical calculations proceed in cancer cell apoptosis regulation without the general limiations of lithography in nanotechnology. As such, this work provides a new vision for the construction of a logic-gated modular nanocalculator with logical calculation proficiency potentially useful in cancer therapy and the regulation of life.

Erythrocyte-derived drug delivery systems greatly promoted the development of anti-cancer agents, especially nanoparticles. The fabrication and application of these systems were summarized in this review from four different aspects of cancer therapy: cancer enzyme therapy, delivering chemotherapeutic agents, combining with nanoparticles, and several miscellaneous anti-cancer agents.

In this work, homo-FRET (Förster resonance energy transfer between the same kind of fluorophores) takes place in a hetero-FRET (FRET between two different fluorophores) system and can effectively improve the energy transfer efficiency. Herein, a novel ratiometric fluorescence method was developed for the detection of nuclease activity. Exonuclease III (Exo III), an enzyme which has a high exodeoxyribonuclease activity for double-stranded DNA (dsDNA) in the 3′ to 5′ direction, was chosen as a proof of concept of this strategy. In a linear dsDNA template, the occurrence of homo-FRET in two Cy3 donors enables the highly efficient transfer of energy to the Cy5 acceptor. The ratio of fluorescence intensity between Cy3 and Cy5 (FD/FA) increases in an Exo III concentration-dependent manner, which built the foundation of Exo III quantification. This method exhibits a linear range from 0.25 to 8 U mL−1with a detection limit of 0.17 U mL−1. Importantly, this platform also shows the potential for screening Exo III inhibitors and detecting Exo III activity in complex samples.

Magnetic mesoporous silica microspheres with core–shell structure and large pores are highly desired in macromolecules delivery and biocatalysis, biospeparation, and adsorption. In this work, a controllable solvent evaporation induced solution-phase interface co-assembly approach was developed to synthesize core–shell structural magnetic mesoporous silica microspheres with ultralarge mesopore size (denoted as LP-MMS). The synthesis was achieved by employing large-molecular-weight amphiphilic block copolymers poly(ethylene oxide)-block-poly(methyl methacrylate) (PEO-b-PMMA) and small surfactant cetyltrimethylammonium bromide as co-templates, which can co-assemble with silica source in tetrahydrofuran/water solutions. The obtained LP-MMS microspheres possess uniform rasberry-like morphology with a diameter of 600 nm, large primary spherical mesopores (ca. 36 nm), large specific surface area (348 m2/g), high specific pore volume (0.59 cm3/g), and fast magnetic responsivity with high magnetization (15.9 emu/g). The mesopore morphology can be transformed from spherical to cylindrical through introducing a shearing force during the interfacial co-assembly in the synthesis system. The designed LP-MMS microspheres turn out to be good carriers for enzyme (trypsin) immobilization with a high loading capacity of 80 μg/mg and demonstrate excellent biocatalysis efficiency up to 99.1% for protein digestion within 30 min and good recycling stability with negligible decay in digestion efficiency after reuse for five times.

Cell signal transduction mediated by cell surface ligand‐receptor is crucial for regulating cell behavior. The oligomerization or hetero‐aggregation of the membrane receptor driven by the ligand realizes the rearrangement of apoptotic signals, providing a new ideal tool for tumor therapy. However, the construction of a stable model of cytomembrane receptor aggregation and the development of a universal anti‐tumor therapy model on the cellular surface remain challenging. This work describes the construction of a “multi‐catcher” flexible structure GC‐chol‐apt‐cDNA with a suitable integration of the oligonucleotide aptamer (apt) and cholesterol (chol) on a polymer skeleton glycol chitosan (GC), for the regulation of the nucleolin cluster through strong polyvalent binding and hydrophobic membrane anchoring on the cell surface. This oligonucleotide aptamer shows nearly 100‐fold higher affinity than that of the monovalent aptamer and achieves stable anchoring to the plasma membrane for up to 6 h. Moreover, it exerts a high tumor inhibition both in vitro and in vivo by activating endogenous mitochondrial apoptosis pathway through the cluster of nucleolins on the cell membrane. This multi‐catcher nano‐platform combines the spatial location regulation of cytomembrane receptors with the intracellular apoptotic signaling cascade and represents a promising strategy for antitumor therapy. A universal nanoplatform integrating multi‐site membrane anchoring of cholesterol and multivalent affinity catching of the aptamer regulates the cluster of plasmalemma nucleolins to induce tumor cell apoptosis. In addition, it combines the spatial location regulation with apoptotic signaling transduction and breaks the traditional shuttle drug delivery mode of nucleolin, which is expected to be a promising anti‐tumor strategy.

In recent past, the plasma-assisted ignition has been explored for applications on a variety of engines. The plasma ignition has been shown to possess special advantages such as reducing the ignition delay time, improving the reliability, and reducing the NOx emissions. By using a plasma jet ignition experimental system, the plasma jet ignition of argon-discharge arc has been investigated. Owing to the characteristics of high temperature, the mixture can be easily ignited by the plasma jet. Through the propane–air mixture ignition experiments, the ignition limits of the plasma jet and spark ignition are investigated. The results show that the plasma jet ignition could extend the ignition limits of propane–air mixture obviously. The ignition limit extends with the increase in the air flow rates. The average ignition limit (the gap between rich and lean limit) of spark ignition and plasma jet ignition are 2.34 and 2.57, respectively. The average ignition limit of the propane–air mixture extends by 9.8%. The plasma jet ignition limit extends with increasing arc current, and the degree of extending plasma jet ignition limit increases with increasing air flow rates. The average ignition limits of 5.7 A and 20.3 A are 2.57 and 2.79, respectively. The average ignition limit of the propane–air mixture extends by 8.5%. The plasma jet ignition limit extends with increasing argon flow rates. The average ignition limits of 200 L/h and 250 L/h are 2.79 and 3.08, respectively. The average ignition limit of the propane–air mixture extends by 10.4%.

DNAzyme amplifiers have been extensively explored as a useful sensing platform, but single DNAzyme amplifier is limited in biosensing applications by its low sensitivity. Herein, a cascade DNAzyme amplifier was designed by exploiting concurrent amplification cycle principles of toehold-mediated strand displacement reaction (TSDR) and Zn2+-assisted DNAzyme cycle with lower cost and simpler procedures. Compared with single DNAzyme amplifier, the proposed TSDR-propelled cascade DNAzyme amplifier exhibited higher sensitivity by releasing more DNAzyme through TSDR to cleave substrate strand during the DNAzyme cycle. Base on this, let-7a could be sensitively detected in the range of 5–50 nmol/L with a detection limit of 64 pmol/L. Furthermore, the dual signal amplification strategy of the cascade DNAzyme amplifier exhibited excellent selectivity to distinguish single-base mismatched DNA strands, which has been successfully applied to the determination of let-7a in blood serum, showing high promise in early cancer diagnosis.

The exploration of TiO2nanostructures with fast electron transport and large specific surface area is essential for their applications in solar cells. For this aim, bunchy TiO2hierarchical spheres (BS-TiO2), consisting of multiple TiO2microspheres constructed by nanosheets and the 1D TiO2nanobelt, were rationally designed and fabricated. BS-TiO2enables the much fast charge transport properties in the photoanode (with a long electron diffusion length of 36μm) and shows large specific surface area (higher than 200m2/g), leading to excellent electron collection and light harvesting, which enable the increased conversion efficiency of the dye-sensitized solar cell by 34% for BS-TiO2photoanode (7.5%) compared to nanoparticle (P25) photoanode. This work provides an important approach for the rational design of the TiO2nanostructures, which also implies the application of the bunchy TiO2hierarchical spheres in other type of solar cells, artificial photosynthesis, and other optoelectronic applications.

A highly transparent and efficient counter electrode was facilely fabricated using SiO2/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT–PSS) inorganic/organic composite and used in bifacial dye-sensitized solar cells (DSCs). The optical properties of SiO2/PEDOT–PSS electrode can be tailored by the blending amount of SiO2and film thickness, and the incorporation of SiO2in PEDOT–PSS provides better transmission in the long wavelength range. Meanwhile, the SiO2/PEDOT–PSS counter electrode shows a better electrochemical catalytic activity than PEDOT–PSS electrode for triiodide reduction, and the role of SiO2in the catalytic process is investigated. The bifacial DSC with SiO2/PEDOT–PSS counter electrode achieves a high power conversion efficiency (PCE) of 4.61% under rear-side irradiation, which is about 83% of that obtained under front-side irradiation. Furthermore, the PCE of bifacial DSC can be significantly increased by adding a reflector to achieve bifacial irradiation, which is 39% higher than that under conventional front-side irradiation.

A novel inorganic/organic nanocomposite film composed of Sinanoparticles (NPs) and poly-(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT–PSS) is obtained from a simple mechanical mixture of SiNPs powder and aqueous PEDOT–PSS solution. Employing this composite film as a counter electrode, dye-sensitized solar cell (DSSC) exhibits an efficiency of 5.7% and a fill factor of 0.51, which are much higher than these of DSSC using pristine PEDOT–PSS electrode (2.9% and 0.25, respectively). The improvements in the photovoltaic performance of the former are primarily derived from improved electrocatalytic performance of the electrode, as evidenced by electrochemical measurements, the composite electrode has lower impedance and higher electrocatalytic activity when in comparison with pristine PEDOT–PSS electrode. These improvements are primarily deriving from the increased electrochemical surface by the addition of SiNPs. The characteristics of SiNPs/PEDOT–PSS composite counter electrode reveal its potential for the use of low-cost and stable Pt-free counter electrode materials. In addition, the results achieved in this work also provide a facile and efficient approach to improve the photovoltaic performance of DSSCs using PEDOT–PSS electrodes.