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Charge transfer complexes (CTCs) have become a promising and new class of photothermal conversion materials, in which the donor and acceptor can be regulated to control the energy gap, facilitating efficient absorption of near-infrared light. However, the successful co-crystallization of appropriate donor and acceptor pairs to form CTCs remains a challenging endeavor, as it requires addressing crucial issues including structural matching, co-assembly and crystallization conditions. Herein, on the basis of retaining the 'autonomy' of the assembly process, we leverage charge transfer and electron transfer processes of pyridinium building blocks to manipulate the photothermal behaviour in two distinct CTCs. Notably, CTC-1OH exhibits electron transfer initiated near-infrared photothermal conversion, while CTC-2OH has an intrinsic charge transfer-dependent photothermal effect with a photothermal efficiency as high as 35.4%. This work opens a new avenue for the development and optimization of the photothermal effect of CTCs. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) produced and metabolized by mitochondria is closely associated to human physiological function, but its mechanism is not fully revealed due to the difficulty in determining the dose of hydrogen sulfide. Therefore, fluorescent probes with both excellent mitochondrial targeting ability and rapid H2S detection are urgently needed. In this work, a novel fluorescent probe, TPAS-TN, was developed to detect H2S in mitochondria. TPAS-TN with a D–π–A structure had a large Stokes shift (213 nm), and possessed low background interference in cell imaging. By introducing a twisted triphenylamine group as the donor, TPAS-TN was endowed with AIE properties, and the positively charged pyridium unit was the acceptor, so that TPAS-TN exhibited good mitochondrial targeting ability and biocompatibility. Meanwhile, the π-bridge was composed of phenyl and dinitrophenyl (DNP) ether to make TPAS-TN exhibit "off–on" properties, low detection limit (69.5 nM), and high sensitivity and selectivity. Besides, TPAS-TN with the above characteristics was successfully applied to high-contrast H2S imaging in mitochondria. [ABSTRACT FROM AUTHOR]

The first catalytic asymmetric interrupted Attanasi reaction has been established. Under the catalysis of a bifunctional organocatalyst, the condensation of cyclic β-keto esters with azoalkenes readily occurred, delivering a variety of bicyclic fused 2,3-dihydropyrroles with vicinal quaternary stereogenic centers in good yields and with good to excellent enantioselectivities (27 examples, up to 96% yield and 95% ee). [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol)-block-poly(L -lactide) (PEG–PLLA) is a biodegradable copolymer, which is widely applied to medicine and drug systems, and its morphology, organization and mechanical properties have been extensively investigated. However, the crystallization kinetics was not studied systemically with different block lengths, which is significant for the performance regulation and understanding of the crystallization behavior of block copolymers. In this study, PLLA, methoxy poly(ethylene glycol)-block-PLLA (MPEG-PLLA) diblock and PLLA–PEG–PLLA triblock copolymers with various molecular masses were melted and isothermally crystallized at different temperatures (Tc), and the crystallization kinetics of the PLLA and PLLA blocks was investigated using a differential scanning calorimeter (DSC). The results indicated that the crystallization kinetics of the PLLA block strongly relies on the architecture and block length. The crystallization rate first decreased and then increased with the increase in Tc for most of the specimens. The highest crystallization rate was found at 110 °C for all investigated PLLA samples. In the case of MPEG4-PLLA copolymers, the highest crystallization rate was observed at 100 °C. With the increase in the block length of PEG, the crystallization rate increased and the highest crystallization rate was found at lower a Tc value. High n values were found for block copolymers when crystallized at a relatively low temperature, which might be due to the dispersion of PEG in the interlamellar and interfibrillar regions of PLLA crystallites, and branched or dendritic structures developed upon subsequent crystallization. [ABSTRACT FROM AUTHOR]

Photoinduced bending behavior triggered by [2 + 2] cycloaddition of a photoactive complex has been successfully achieved, accompanied by photochromic and fluorescence changes that provide convenience for long-distance observation of photomechanical motion. The key design feature is based on the introduction of flexible methylene groups and cation–π interactions. Moreover, the potential application in photomechanical devices was reflected by bending and supporting force experiments on the complex composite film, which is of increasing importance especially in soft actuators and robots. [ABSTRACT FROM AUTHOR]

Liquid biopsy is becoming an innovative tool in precision oncology owing to its noninvasive identification of biomarkers circulating in the body fluid at various time points for continuous and real-time analysis of disease progression. MicroRNAs in blood exosomes are identified as a new promising class of potential biomarkers for cancer diagnostics and prognostics. Conventional detection of blood exosomal microRNAs need multiple-step, complicated, costly, and time-consuming sample preparation of exosomes isolation and RNA extract, which affect the accuracy and reproducibility of analytical results. In this work, we set up an in situ quantitative analysis of human plasma exosomal miR-1246 by a probe of 2′-O-methyl and phosphorothioate modified molecular beacon. The probe has outstanding nuclease resistance in highly active RNase A/T1/I, which makes it stable for direct application in blood samples. With rapid rupture of exosomes membrane by Triton X-100, the probe can enter exosomes to specifically target miR-1246 exhibiting quantitative fluorescent signals. Using the output signals as a diagnostic marker, we differentiated 33 breast cancer patients from 37 healthy controls with 97.30% sensitivity and 93.94% specificity at the best cutoff. The blood biopsy is simple without extracting plasma exosomes and their nucleic acids content, time-saving in about 2 h of total analysis process, and microvolumes needed for plasma sample, suggesting its good potential to clinical application. [ABSTRACT FROM AUTHOR]

Enantioselective fluorescent sensors show large potential for fast, real-time, and highly sensitive measurement of the concentration and enantiomeric composition of chiral molecules. Among all of the sensors, BINOL-based sensors have been actively investigated and extensively used to carry out highly enantioselective, sensitive recognition of chiral α-hydroxycarboxylic acids, amino acids, amino acid derivatives, amino alcohols and amines. In this manuscript, the recent progress of chiral BINOL-based sensors for enantioselective fluorescence recognition of different substrates is reviewed and discussed. The structure of BINOL is tuned by introducing various groups or molecules which systematically changed its fluorescence properties and offered potential for rapid assays of chiral organic molecules. From the development of this area, we gain fresh insight into the challenges and chances of BINOL-based sensors. [ABSTRACT FROM AUTHOR]

In this study, we report a facile one-pot chemical etching approach to simply and rapidly prepare gold nanoclusters capped with luminol (Lum-AuNCs) in an alkaline aqueous solution at room temperature. A series of characterization studies have been carried out to explore the morphology, the optical properties and chemical components of Lum-AuNCs. The average diameter of Lum-AuNCs is 1.8 ± 0.3 nm, exhibiting fluorescence near 510 nm upon excitation at 420 nm with a quantum yield of 14.29% and an average fluorescence lifetime of 9.47 ns. On the basis of the ligand-induced etching of glutathione (GSH) to the intermediate (luminol capped gold nanoparticles, abbreviated as Lum-AuNPs), a novel and simple method for the fluorescence determination of GSH has been established. The method displays a good linear response in the range of 0.05–300 μM toward GSH with a limit of detection of 35 nM. This detection strategy with high sensitivity and selectivity facilitates its practical application for the detection of GSH levels in cell extracts. The in vitro cell results illustrate that Lum-AuNCs have good cytocompatibility and can be used to readily differentiate normal cells and tumor cells. [ABSTRACT FROM AUTHOR]

Silicon has received much attention due to its high theoretical capacity as the electrode of lithium-ion batteries (LIBs). However, the poor stability caused by the volume expansion problem affects the cycle life of batteries, thus severely limiting the application of the silicon anode. In the present work, we engineered silicon nanotubes with hollow-structure to accommodate the volume expansion of silicon and improve the electrochemical stability of lithium ion batteries. Hollow silicon nanotubes were in situ synthesized on carbon cloth (HSiNTs/CC) by reducing silicon oxide and corroding zinc oxide nanorod templates and directly used as the anode of lithium-ion batteries without any binders or conductive additives. The results of electrochemical measurements indicated that HSiNTs/CC exhibits superior LIB performance with excellent cycling stability and good rate capability. At a current density of 100 mA g−1, a reversible capacity of 1420 mA h g−1 was achieved and the fabricated LIB could retain 93.7% of the initial capacity after 100 cycles. Even at a decoupled current density of 1000 mA g−1, the LIB still possesses a capacity of 1026 mA h g−1 and 98.3% capacity retention after 100 cycles. The results demonstrated that the thin hollow structures were well suited to accommodate the volume expansion of silicon and improve the stability of the HSiNTs/CC anode during the lithiation–delithiation cycles, which shines some light on the reasonable design and preparation of silicon anodes for ultra-stable lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Easy and cost-effective production of high-quality photonic crystals (PCs) remains challenging but attractive, not just because they are a type of gemstone but more for their scientific applications (e.g., serving as lossless waveguides, visual sensors, novel pigments and novel separation media). Herein presented is a separation-cooperated assembly (SCA) strategy able to organize cheap polydisperse particles into PCs. Its feasibility was validated through sink-induced SCA of poorly disperse (size variation up to 56%) particles into iridescent liquid PCs in 3 days or more. Strikingly, with a sharp photonic band gap down to 10 nm (ca. 1/7 of the reported 66 nm), the liquid PCs are able to cyclically recover their iridescent color in ca 20 s after agitation, and keep their structural order after dryness, making them practicable to write and paint directly. Also significant is that SCA yielded uniform particles with size variation down to 0.7%. It is thus an easy way to isolate homogeneous particles from disperse ones. [ABSTRACT FROM AUTHOR]

Multicomponent ring-opening/Huisgen cycloaddition reactions combined with CO2 capture with a polyurea-encapsulated copper salt as a catalyst that in situ formed from simple CuCl and soluble polyurea during the reaction were carried out successfully for the synthesis of β-hydroxytriazoles under exceptionally mild conditions, in which the polyurea-encapsulated copper(i) chloride proved to be a robust and recyclable catalyst system with high yields as well as excellent chemoselectivity in this reaction. [ABSTRACT FROM AUTHOR]

Trapping and sorting of micro-sized objects is one important application of lab on a chip devices, with the use of acoustic bubbles emerging as an effective, non-contact method. Acoustically actuated bubbles are known to exert a secondary radiation force (FSR) on micro-particles and stabilize them on the bubble surface, when this radiation force exceeds the external hydrodynamic forces that act to keep the particles in motion. While the theoretical expression of FSR has been derived by Nyborg decades ago, no direct experimental validation of this force has been performed, and the relationship between FSR and the bubble's ability to trap particles in a given lab on a chip device remains largely empirical. In order to quantify the connection between the bubble oscillation and the resultant FSR, we experimentally measure the amplitude of bubble oscillations that give rise to FSR and observe the trapping and release of a single microsphere in the presence of the mean flow at the corresponding acoustic parameters using an acoustofluidic device. By combining well-developed theories that connect bubble oscillations to the acoustic actuation, we derive the expression for the critical input voltage that leads to particle release into the flow, in good agreement with the experiments. [ABSTRACT FROM AUTHOR]

We demonstrate a new approach to synthesize several unique nanostructures by tuning the selective reactivities on individual symmetry-breaking segmented selenium nanorods (SBS-SeNRs). The segment-selective reactions from thiolated silane endowed the formation of float-like SBS-SeNR@SiO2 with a silica coating on the t-Se segment. Several other unique nanostructures were further synthesized by applying other selective reactions, such as Se chemical removal and nanogold deposition. Such a segmented nanomaterial of SBS-SeNRs acts as a new chemical template for preparing various segmented nanocomposites. [ABSTRACT FROM AUTHOR]

A cobalt-based molecular catalyst was successfully grafted to a fullerene derivative via‘click’ chemistry on an electrode for both electro-catalytic and light driven water reduction. Using an organic photovoltaic electrode immobilized with a cobalt catalyst as the photocathode, the photoelectrochemical cell displayed a stable photocurrent. [ABSTRACT FROM AUTHOR]

Three novel indole-based ligand precursors [HIndPhR, R = methoxy, HIndPhOMe (2a); thiomethoxy, HIndPhSMe (2b); and N,N′-dimethylamino, HIndPhNMe2 (2c)] have been synthesized via Sonogashira and cyclization reactions with moderate to high yield. Reactions of these ligand precursors with 0.6 equivalent of MgnBu2 in THF afforded the magnesium bis-indolyl complexes 3a–3c, respectively. All the ligand precursors and related magnesium complexes have been characterized by NMR spectroscopy and elemental analyses. The molecular structures are reported for compounds 3a and 3b. Under optimized conditions, compound 3a demonstrates efficient catalytic activities towards the ring opening polymerization of l-lactide and ε-caprolactone in the presence of BnOH. [ABSTRACT FROM AUTHOR]

The search for laser-ignitable energetic materials catering to the safety and accuracy requirements in military and civilian affairs is an important yet challenging task. In this work, non-explosive and stable nitro bearing ligands of 3,5-dinitro-4-chlorobenzoic acid (HDNB-Cl) and 3,5-dinitro-4-hydroxybenzoic acid (HDNB-OH) have been adopted as energetic modules and organic building units to assemble with copper ions to construct energetic coordination complexes. The d–d transition introduced by Cu2+ endows the as-synthesized compounds to display remarkable absorptions of NIR light, and thus achieve efficient photothermal conversions upon irradiation by an 808 nm laser. As a result, the DNB-Cl based complexes can be laser-ignited and strong deflagration has been observed. The satisfactory thermal stability and tolerance toward friction and electrostatic discharge make them good candidates as laser-ignitable energetic materials. Unlike the conventional energetic materials based on nitrogen-rich organics (e.g., azido, furazan, and heterocyclic compounds), this work reveals that the easily functionalized nitro-bearing carboxylate ligand is an alternative energy module for assembling stable energetic complexes, and the coordination interaction-induced photothermal conversion would be an efficient strategy to achieve laser ignition for the resultant energetic compounds. [ABSTRACT FROM AUTHOR]

An effective NH4Cl-assisted method for purification of carbon nanotube (CNT) macro-films is reported. Compared to previous oxidation in acid, this method induces little destruction to the graphitic structure of CNTs, and more importantly, the morphology and integrity of the macroscopic film are maintained. [ABSTRACT FROM AUTHOR]

The efficiency of excess electron transport in duplex DNA can be enhanced by limiting the pathways available for migration and using a donor of moderate strength that suppresses radical recombination through selective electron transfer to distal pyrimidines rather than proximal purines. [ABSTRACT FROM AUTHOR]

A dispersible graphene/gold nanoclusters hybrid in aqueous solution was fabricated in situbased on the bilayer graphene template, and its electrogenerated chemiluminescence (ECL) behavior was studied. [ABSTRACT FROM AUTHOR]

Small-molecule (SM) donor based ternary organic solar cells (OSCs) have drawn increasing attention owing to the remarkable photovoltaic performances achieved recently. In this study, a chlorinated benzodithiophene core and selenophene-containing π bridge based SM donor, namely CBTSeHR, was used as an SM donor guest to fabricate ternary OSCs owing to its favorable optoelectronic properties. CBTSeHR exhibits a good complementary absorption band and matched energy levels with the prevailing polymer donors and SM nonfullerene acceptors (NFAs), which is beneficial to light harvesting and charge transport. In addition, the incorporation of CBTSeHR could modulate the micro morphology and endow the ternary blend with more favorable phase separation size. Accordingly, the as cast ternary device prepared by introducing CBTSeHR into the D18:CH-6F host system exhibits an excellent power conversion efficiency (PCE) of 17.33%, which is even higher than that of the optimal binary host device (17.08%). After thermal annealing (TA) treatment, an outstanding PCE value of 18.41% with a high Voc of 0.901 V, FF of 0.767, and Jsc of 26.64 mA cm−2 was achieved, demonstrating the great success of SM donor based ternary OSCs. [ABSTRACT FROM AUTHOR]

One major challenge in current brain research is generating an integrative understanding of the brain's functions and disorders from its multiscale neuronal architectures and connectivity. Thus, innovative neurotechnology tools are urgently required for deciphering the multiscale functional and structural organizations of the brain at hierarchical scales from the molecular to the organismal level by multiple brain research initiatives launched by the European Union, United States, Australia, Canada, China, Korea, and Japan. To meet this demand, microfluidic chips (μFCs) have rapidly evolved as a trans-scale neurotechnological toolset to enable multiscale studies of the brain due to their unique advantages in flexible microstructure design, multifunctional integration, accurate microenvironment control, and capacity for automatic sample processing. Here, we review the recent progress in applying innovative μFC-based neuro-technologies to promote multiscale brain research and uniquely focus on representative applications of μFCs to address challenges in brain research at each hierarchical level. We discuss the current trend of combinational applications of μFCs with other neuro- and biotechnologies, including optogenetics, brain organoids, and 3D bioprinting, for better multiscale brain research. In addition, we offer our insights into the existing outstanding questions at each hierarchical level of brain research that could potentially be addressed by advancing microfluidic techniques. This review will serve as a timely guide for bioengineers and neuroscientists to develop and apply μFC-based neuro-technologies for promoting basic and translational brain research. [ABSTRACT FROM AUTHOR]

Luminescent phthalimidino derivatives 2- and 4-(1-oxo-1H-2,3-dihydroisoindol-2-yl)benzoic acid were prepared and characterized, and their crystallization revealed a new approach for the crystallization of an organic compound which is induced by a reaction but not the synthetic reaction itself. [ABSTRACT FROM AUTHOR]

A novel photocatalytic water splitting device was constructed using economic graphene quantum dots as a photocatalyst and a Ni-based complex [(tpy-CH＝N)2Ni]Cl2 (tpy = terpyridine) as a co-catalyst. Under visible light irradiation and with a bias of −0.1 V vs. NHE, it produced an extremely stable photocurrent density of −9 μA cm−2 for 3 h. [ABSTRACT FROM AUTHOR]

Herein, we have designed and synthesized a quinolinyl-AIE photosensitizer (TPE-4QL+) with an alternative elevated intersystem crossing (ISC) rate, which exhibits not only highly efficient photosensitivity but also high tumor cell specificity and an excellent mitochondrial targeting ability. In vitro experiments indicate that using TPE-4QL+ as a photosensitizer can induce a series of tumor cells to die with a low dose of radiation, but with no obvious toxicity to normal cells. The in vivo studies on a mouse model bearing a subcutaneous 4T1 xenograft also show that TPE-4QL+ can be used with high efficiency as a photosensitizer in PDT. [ABSTRACT FROM AUTHOR]

A robust metal-free catalytic strategy for the rapid construction of the valuable α-hydroxy-α-CF3-γ-ketoester skeleton with cheap and easily available stock chemicals (alkynes and trifluoropyruvate) as the starting material is described. This protocol shows very good functional group tolerance and is easily scaled up. Importantly, compared with transition metal-catalyzed methods, this strategy is made more environmentally friendly by employing a catalytic amount of H3PO4 as the catalyst. [ABSTRACT FROM AUTHOR]

A mass-tagged metal–organic framework (MOF) nanoprobe approach was developed for ultra-sensitive quantification of platelet protein CD44 by integrating activable aptamer recognition and MOF nanoprobe signal amplification with mass spectrometric detection. This approach offered high sensitivity and quantitative capability for low abundant protein analysis in tumor-educated platelets (TEPs), exhibiting great potential in cancer diagnosis and management. [ABSTRACT FROM AUTHOR]

A high power output, membrane-less formic acid/O2 enzymatic biofuel cell was fabricated, in which nitrogen-doped graphene was proven to be effective for recycling the NAD+/NADH cofactor at a nitrogen-doped graphene/gold nanoparticle/formate dehydrogenase bioanode in the catalytic oxidation of formic acid. [ABSTRACT FROM AUTHOR]

Graphene oxides with different surface charges were fabricated from carboxylated graphene oxide by chemical modification with amino- (–NH2), poly-m-aminobenzene sulfonic acid- (–NH2/–SO3H), or methoxyl- (–OCH3) terminated functional groups. The chemically functionalized graphene oxides and the carboxylated graphene oxide were characterized by infrared spectroscopy, X-ray photoelectron spectroscopy, UV-Vis spectrometry, ζ potential measurements, field emission scanning electron microscopy, and contact angle analyses. Subsequently, the resulting graphene oxides were used as substrates for culturing primary rat hippocampal neurons to investigate neurite outgrowth and branching. The morphological features of neurons that directly reflect their potential capability in synaptic transmission were characterized. The results demonstrate that the chemical properties of graphene oxide can be systematically modified by attaching different functional groups that confer known characteristics to the substrate. By manipulating the charge carried by the functionalized graphene oxides, the outgrowth and branching of neuronal processes can be controlled. Compared with neutral, zwitterionic, or negatively charged graphene oxides, positively charged graphene oxide was found to be more beneficial for neurite outgrowth and branching. The ability to chemically modify graphene oxide to control neurite outgrowth could be implemented clinically, especially in cases wherein long-term presence of outgrowth modulation is necessary. [ABSTRACT FROM AUTHOR]

Solution-processable 4,4′,4″-{[9,9-bis(hexyl)-9H-fluorene-2,4,7-triyl]tri-2,1-ethenediyl}tris(N,N-diphenyl)benzeneamine (TF), consisting of a fluorene core and terminal triphenylamine groups, was synthesized by the Wittig reaction. The characteristics of TFwere analyzed by 1H-NMR, elemental analysis, differential scanning calorimetry, optical spectra, cyclic voltammetry, and atomic force microscopy. The triphenylamine terminals were intentionally incorporated to increase its hole-transporting ability that reduces the barrier height of hole-injection. A multilayer light-emitting diode using TFas a hole-transporting layer [ITO/PEDOT:PSS/TF/Alq3(70 nm)/LiF(0.5 nm)/Al(100 nm)] was readily fabricated by the spin-coating process. Its maximum brightness (9390 cd m−2) and current efficiency (2.90 cd A−1) were superior to those using conventional NPB as a hole-transporting layer. In addition, the TFcould also be blended with polyfluorene (PF) to be applied as an emitting layer; the devices [ITO/PEDOT:PSS/blend (110 nm)/LiF(0.5 nm)/Ca(50 nm)/Al(100 nm)] exhibited high maximum brightness (4040 cd m−2) and current efficiency (1.62 cd A−1). Our results indicate that the TFis a potential optoelectronic material which is readily processed by wet processes. [ABSTRACT FROM AUTHOR]

An eco-friendly and economical approach for the photocatalytic oxidation of organic inter-mediates by air under mild conditions is highly desirable in green and sustainable chemistry, where the photogeneration of active oxygen species plays a key role in improving conversion efficiency and selectivity. By using pyridinium derivatives as molecular mediators for electron transfer and energy transfer, the simultaneous activation of O2 from air into superoxide radicals and singlet oxygen species can be achieved, and a photoinduced electron transfer catalytic system for the oxidation of alcohols has been developed. Thus, we have successfully simplified the complicated catalytic system into a single molecular catalyst without any additional noble metals and co-catalysts/additives. The current photocatalytic system shows high catalytic efficiency not only for aromatic alcohols but also for aliphatic alcohols that are generally difficult to undergo aerobic oxidation at room temperature under air atmosphere, representing an ideal photocatalytic platform for green and economical organic syntheses. [ABSTRACT FROM AUTHOR]

The osmium(VI) nitrido complex [OsVI(N)(sap)(py)Cl] is a potential anti-cancer drug with promising in vitro antiproliferative activities toward a panel of cancer cell lines, including cisplatin-resistant cells (IC50 values of 2.8–13.8 μM). This drug targets DNA and changes its conformation via covalent binding and insertion. In vitro studies indicate that the drug induces HepG2 cells G2/M phase arrest, disrupts the mitochondrial membrane potential and causes caspase-mediated apoptosis. Further in vivo studies using HepG2-bearing nude mice reveal that this drug not only shows good antitumor efficacy of inhibiting tumor growth, but also does not show the side effect of weight loss. [ABSTRACT FROM AUTHOR]

Optical techniques using developed laser and optical devices have made a profound impact on modern medicine, with "biomedical optics" becoming an emerging field. Sophisticated technologies have been developed in cancer nanomedicine, such as photothermal therapy and photodynamic therapy, among others. However, single-mode phototherapy cannot completely treat persistent tumors, with the challenges of relapse or metastasis remaining; therefore, combinatorial strategies are being developed. In this review, the role of light in cancer therapy and the challenges of phototherapy are discussed. The development of combinatorial strategies with other therapeutic methods, including chemotherapy, immunotherapy, gene therapy, and radiotherapy, is presented and future directions are further discussed. This review aims to highlight the significance of light in cancer therapy and discuss the combinatorial strategies that show promise in addressing the challenges of phototherapy. [ABSTRACT FROM AUTHOR]

A dual-photoresponsive coordination polymer displaying color-distinguishable olefin/cyclobutane-linked pyridinium radical states through photoinduced electron transfer and photocycloaddition has been successfully assembled based on the monoquaternized trans-1,2-bis(4-pyridyl)ethylene and electron-rich benzenetetra-carboxylate anion. The synergy of charge-transfer and cation–π interactions within the framework endows the compound with excellent stability toward high temperature (350 °C), acidic/basic environments (pH = 2–12) and organic solvents. Reversible recovery from the radical states to their initial states, and reverse-cyclization can be achieved upon heat-treatment. [ABSTRACT FROM AUTHOR]

Compared with normal cells, cancer or tumor cells have a specific microenvironment and apparently possess a relatively large amount of ROS/RNS, and their overexpression is one of the important reasons for tumor development and deterioration. Therefore, monitoring the changes of intracellular ROS/RNS can improve the awareness of the clinical manifestations of the disease, which will be beneficial for the early diagnosis of cancer and improving treatment efficiency. Herein, in this study we have exploited and constructed a novel strategy based on the SiC@C nanowire electrode for intracellular electrochemical analysis to monitor ROS levels in cancer or tumor cells. Firstly, the SiC@C nanowire electrode was utilized to detect the intracellular ROS radical changes involved in the relevant biological processes of cancer cells where fluorescent zinc nanoclusters were biosynthesized in situ in target cancer cells by using the intracellular microenvironment and specificity of these cancer cells. By combining a confocal fluorescence microscopy study simultaneously, our observations illustrate that accompanied by the apparent change of the intracellular ROS, these in situ biosynthesized fluorescent nanoclusters gradually accumulate inside the cytosolic area with the increase of the reaction time. Moreover, it is evident that the size of the SiC@C nanoelectrodes can match the single cell dimensions, and its unique high spatial resolution provides the possibility of relevant intracellular molecular detection. These nanoelectrochemical biosensors can be adopted to quantitatively determine the change of the ROS content in target single cells in the relevant biological microenvironment or during the in situ biosynthesis process, and are also beneficial for understanding the related mechanism of some specific biological processes including the in situ synthesis at the single cell level. [ABSTRACT FROM AUTHOR]

Histone post-translational modification (PTM) is a marker for gene transcription and is involved in a range of cancers, such as breast cancer. Most importantly, different modifications of a specific site (e.g., mono-, di- and tri-methylations and acetylation at a lysine residue) are individually enriched in particular regions of the genome, indicating that they may serve distinct functions. How these patterns are built and whether downstream events are dependent on the precise site-specific modification status are still poorly understood. One of the prerequisites is to obtain quantitative information on individual modification forms. Currently, the low abundance of these forms creates a great challenge. In this study, a targeted proteomics assay based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with single template oriented molecularly imprinted polymers (MIPs) was developed to attempt to simultaneously quantify site-specific histone mono-, di- and tri-methylated and acetylated forms. Surrogate peptides, including an unmodified one, were selected as targets in both MIP enrichment and subsequent LC-MS/MS detection. As a consequence, a limit of quantification (LOQ) of ∼0.5 nM was achieved, which was 10-fold more sensitive than without MIPs and much more sensitive than mass spectrometry involving a scanning mode. Finally, the assay was employed to quantitatively analyze the H3K79, H3K122 and H4K31 modification status in human breast cell lines. [ABSTRACT FROM AUTHOR]

High-throughput proteome-level characterization of stemness markers of MCF-7 cancer stem cells was carried out using our recently developed site- and structure-specific isotopic-labeling quantitative N-glycoproteomics pipeline. 144 differentially expressed intact N-glycopeptides were quantified all at once yet with good accurate consistency with the individual biochemical measurements of proteins, RNA or DNA. [ABSTRACT FROM AUTHOR]

A series of color-tunable NaBa1−zSrzB9O15:Ce3+,Mn2+ phosphors were synthesized by a high temperature solid state method. Luminescence property, energy transfer, thermal stability and cation substitution were investigated in detail. Due to energy transfer, NaBaB9O15:Ce3+,Mn2+ presents violet to green luminescence and manifest a broad excitation range from 200 to 350 nm. The energy transfer mechanism of Ce3+–Mn2+ is identified as a dipole–dipole interaction. NaBa1−zSrzB9O15:Ce3+,Mn2+ displays both Ce3+ violet and Mn2+ green and orange emissions under ultraviolet excitation. It is observed that Sr2+ partial substitution for Ba2+ could adjust the ratio of Mn2+ emission intensity in different cation sites, which results from preferred sites’ occupation with modification of the crystal structure. Furthermore, increase in temperature can enhance the energy transfer from Ce3+ to Mn2+, which enhances the Mn2+ emission intensity sharply. The highly thermal-sensitive property of NaBa1−zSrzB9O15:Ce3+,Mn2+ makes it feasible for its potential application in luminescent ratiometric thermometers with wide temperature range. [ABSTRACT FROM AUTHOR]

Herein, we synthesized Pt dendrimer-encapsulated nanoparticles (Pt DENs) using amine-terminated sixth-generation polyamidoamine dendrimers. The enhanced and stable anodic electrochemiluminescence (ECL) of 3-mercaptopropionic acid-capped CdTe quantum dots (QDs) in a tripropylamine solution was achieved owing to Pt DENs. The reason may be that Pt DENs exhibit high catalytic electrochemical oxidation in the presence of tripropylamine and excellent conductive property. Inspired by this, Pt DENs were conjugated with Fe3O4@SiO2 nanoparticles and served as nano-carriers. The capture antibodies were immobilized on the Fe3O4@SiO2-Pt DEN nanocomposites, which possess many attractive advantages such as the ease of bioconjugation, large specific surface area, and convenience of magnetic separation. Fluorescence microscopy images and UV-vis spectra were used to verify the immobilization of capture antibodies on the nanocomposites. The CdTe QDs were applied as signal labels for conjugation of nanocomposites with detection antibodies, which were characterized by agarose gel electrophoresis. Electrochemical impedance spectroscopy and cyclic voltammetry demonstrated the successful preparation of an ECL immunosensor. Under the optimal conditions, the proposed immunosensor provided a wide linear range from 0.005 ng mL−1 to 150 ng mL−1 with a detection limit of 0.2 pg mL−1 (S/N = 3) for the detection of carcinoembryonic antigen. Moreover, the immunosensor showed good performance for the detection of carcinoembryonic antigen in serum samples as well as great potential in clinical bioassay. [ABSTRACT FROM AUTHOR]

A ratiometric two-photon fluorescent probe for SO2 derivatives was first proposed based on acedan–merocyanine dyads via a TP-FRET strategy. It was successfully applied to visualization of the fluctuations of enzymatically generated SO2 derivatives in the mitochondria of HepG2 cells and rat liver tissues using two-photon fluorescence microscopy imaging. [ABSTRACT FROM AUTHOR]

A novel ternary hybrid of carbon nanotubes/graphitic carbon nitride nanosheets/gold nanoparticles was prepared and used as robust substrate electrodes for fabricating membrane-less glucose/O2 enzyme biofuel cells (EBFCs), and a remarkably improved power output was observed for the prepared EBFC. [ABSTRACT FROM AUTHOR]

The supramolecular interaction between the host molecule β-cyclodextrin (β-CD) and the guest molecule adamantane is extensively applied in several disciplines. However, recent studies on the applications of this molecular recognition mainly focused on glass, silicon, and gold substrates. Few studies have explored the field of poly(dimethylsiloxane) (PDMS), an optically transparent elastomer widely used in biological microfluidic devices. In the present study, various functional group-modified adamantyl-terminated dendronized molecules were synthesized via an efficient and facile route. The binding of adamantyl-terminated dendronized molecules onto β-CD-conjugated PDMS surfaces and their reversible dissociation from PDMS surfaces through the competitive mechanism of β-CD-N3 were studied. The results showed that the dissociation is relatively slow compared with the binding, and the former process can be accelerated through exchanging the original β-CD-N3 solution with a fresh one. Afterward, more complex multilayer assemblies were constructed on PDMS surfaces using the host–guest interaction between adamantane and β-CD as well as between biotin and streptavidin. A further study on the association and dissociation of the established multilayer assemblies showed that the assembly constructed with a biotinylated monoadamantyl-terminated molecule has a reversible property, whereas that with a biotinylated triadamantyl-terminated molecule has an irreversible property. These results demonstrated that the reversible properties of the fabricated assembly can be easily modulated on the PDMS surfaces by regulating the valence of the supramolecular interaction between adamantane and β-CD. [ABSTRACT FROM AUTHOR]

An optically active, hyperbranched poly(fluorenevinylene) derivative was synthesized by polymerization of (−)-2,4,7-tris(bromomethyl)-9-neomenthyl-9-pentylfluorene. A spin-coated film sample of the polymer exhibited efficient circularly polarized light (CPL) emission in the visible range of 400–700 nm on photo excitation even without annealing processes leading to chain ordering. [ABSTRACT FROM AUTHOR]

A noncovalent macrocycle-within-noncovalent macrocycle assembly is formed from twelve molecules of (±)-1and twelve molecules of MeOH in the solid state. The H-bonded (MeOH)12cyclododecamer assumes a crown-shaped geometry that has not previously been predicted theoretically or found experimentally. [ABSTRACT FROM AUTHOR]