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Understanding the structural changes and degradation mechanisms of organic pollutants is critical in environmental research. In this work, a xenon lamp was used as an analog light source to simulate the effect of sunlight on 3,3′-diamino-4,4′-azoxyfurazan (DAAF) in aqueous solution. Combining high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS), surface-enhanced Raman spectroscopy (SERS) with density functional theory (DFT), the degradation intermediates and mechanisms of DAAF were investigated. The sequential breakdown of the –NH2and –O–N= bonds, followed by the removal of atomic O from –N=N(O)–, was emphasized and investigated using two-dimensional correlation spectroscopy (2D-COS) and SERS spectra. Three intermediates with mass-to-charge ratios (m/z) 181, 251 and 180 were identified and characterized by integrating experimental SERS data with DFT-calculated Raman spectra based on structures hypothesized from MS spectra. The findings from HPLC–MS and SERS not only corroborate each other but also provide a foundation for a detailed examination of the DAAF degradation process.

Electrochemical methodology has probably been the most used sensing platform in the past few years as they provide superior advantages. In particular, screen-printed electrode (SPE)-based sensing applications stand out as they provide extraordinary miniaturized but robust and user-friendly detection system. In this context, we are focusing on the modification of SPE with functional nucleic acid probes and nanostructures to improve the electrochemical detection performance in versatile sensing applications, particularly in the fight against the COVID-19 pandemic. Aptamers are immobilized on the electrode surface to detect non-nucleic acid targets and complementary probes to recognize and capture nucleic acid targets. In a step further, SPE-based biosensors with the modification of self-assembled DNA nanostructures are emphasized as they offer great potential for the interface engineering of the electrode surface and promote the excellent performance of various interface reactions. By equipping with a portable potentiostat and a smartphone monitoring device, the realization of this SPE-based miniaturized diagnostic system for the further requirement of fast and POC detection is revealed. Finally, more novel and excellent works are previewed and future perspectives in this field are mentioned.

The unique features of solution‐processed quantum dots (QDs) including emission tunability in the visible range, high‐quality saturated color and outstanding intrinsic stability in environment are highly desired in various application fields. Especially, quantum dot light‐emitting diodes (QLEDs) are promising light sources for applications in displays. However, the imbalance injection of holes and electrons have always been a challenging issue of QLED. In this study, the modified ligands which is synthesized by ourselves are incorporated into QDs through solution ligand exchange. The highest occupied molecular orbital (HOMO) of QDs is upshifted from ‐5.65eV to ‐5.35eV, leading to the decrement of the energy gap between the HOMO of QDs and the HOMO of hole transport layer. Through the successful ligands exchange, improvement by factors of 7.5 is achieved in maximum external quantum efficiency (EQE) compared with QLED with OA ligands.

5-amino-4-nitrobenzo[1,2-c:3,4-c']bis([1,2,5]oxadiazole)1,6-dioxide (CL-18) exhibits significant potential as an initiating explosive. However, its current synthesis process remains non-scalable due to low yields and safety risks. In this study, we have developed a simple and safe synthetic route for CL-18. It was synthesized from 3,5-dihaloanisole in a four-step reaction with an overall yield exceeding 60%, surpassing all reported yields in the literature. Subsequently, recrystallization of CL-18 was successfully achieved by carefully selecting appropriate solvents and antisolvents to reduce its mechanical sensitivity. Ultimately, when DMF-ethanol was employed as the recrystallization solvent system, satisfactory product yield (>90%) and reduced mechanical sensitivity (IS = 15 J; FS = 216 N) were obtained. Additionally, CL-18 is derived from the rearrangement of oxygen atoms on i-CL-18 furoxan, and a comparative analysis of their physicochemical properties was conducted. The thermal stability of both compounds is similar, with onset decomposition temperatures recorded at 186 and 182 °C respectively. Similarly, they exhibit 5 s breaking point temperatures of 236 and 237 °C. Additionally, we present novel insights into the positional-isomerization-laser-ignition performance of CL-18 and its isomer i-CL-18 using laser irradiation for the first time. Remarkably, our findings demonstrate that i-CL-18 exhibits enhanced laser sensitivity, as it can be directly ignited by a 1064 nm wavelength laser, whereas CL-18 lacks this characteristic.

The detection of biomolecular analytes is of great importance in clinical, environmental, and argo-food areas, among which the electrochemical methodology is attracting much attention. In particular, screen-printed electrode (SPE)-based sensing applications have exhibited potential possibility for on-site detection, especially for fast clinical biomarker detection, since they provide a miniaturized but robust and portable electrode detection system. In this context, we focused on the modification of SPE with functional antibodies to improve the electrochemical detection performance in versatile sensing applications, particularly for COVID-19 detection. These antibodies were immobilized onto the electrode surface viavarious methodologies, through which the powerful potential from the modification of SPE was revealed. Finally, more novel and excellent works on the biomolecular modification of SPE and the prospects of this technology from its state-of-art status to commercialization are previewed and future perspectives in this field are mentioned.

Bromodomain and extra-terminal (BET) proteins are attractive targets for treating various malignancies including melanoma. The inhibition of BET bromodomains, e.g.with JQ1, is found to downregulate the expression of both c-MYC oncoprotein and programmed cell death ligand 1 (PD-L1), which play a crucial role in tumor growth and the immunosuppressive tumor microenvironment, respectively. The BET bromodomain inhibitors like JQ1 though exhibiting high selectivity and affinity show usually low bioavailability and efficacy in vivodue to fast clearance and inferior uptake by tumor cells. The therapeutic effect of JQ1 might further be lowered by drug resistance. Here, enzyme-responsive micellar JQ1 (mJQ1) was fabricated from a poly(ethylene glycol)-b-poly(l-tyrosine) copolypeptide to enhance JQ1 delivery and the immunotherapy of malignant melanoma. The in vitroresults showed that mJQ1 induced clearly better repression of c-MYC and PD-L1 proteins, cell cycle arrest, cell inhibition, and apoptotic activity than free JQ1 in B16F10 cancer cells. The intratumoral administration of mJQ1 at 2.5 mg of JQ1 equiv. per kg was found to show better inhibition of B16F10 tumors in C57BL/6 mice than the intraperitoneal administration of free JQ1 at 50 mg kg−1. In particular, when combined with radiotherapy, mJQ1 effectively suppressed tumor growth and brought about strong local and systemic antitumor immunity as evidenced by elevated CD8+ T cells and increased ratios of CD8+ T cells to Tregs, affording significantly improved survival of B16F10 tumor-bearing mice than their JQ1 counterparts and marked growth suppression of distant tumors. The great potency of enzyme-responsive micellar JQ1 makes it interesting for immunotherapy of various tumors.

It is well known that imidazoles, possessing two or more nitro substituents, are potential candidates for highly energetic explosives with detonation parameters comparable to those of 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane. 4,4′,5,5′-Tetranitro-2,2′-bi-imidazole (TNBI) is a typical imidazole explosive with energy equivalent to that of RDX but suffers from low sensitivity (impact sensitivity 7 J). 1,1′-Diamino-4,4′,5,5′-tetranitro-2,2′-biimidazole (DATNBI), a derivative of TNBI, possesses two −NH2groups and has a higher detonation velocity (9063 m s–1) and lower impact sensitivity of 15 J, which indicates great potential for future applications. Examination of the thermal decomposition mechanism and kinetics of TNBI and DATNBI gives a more comprehensive view of the influence that the −NH2group has on the sensitivity and storage safety of the energetic explosive-based TNBI molecular skeleton. Herein, the thermal decomposition mechanism is studied, showing that detachment of −NH2groups from DATNBI generates 1-diamino-4,4′,5,5′-tetranitro-2,2′-biimidazole (ATNBI) and TNBI and induces self-decomposition. Although the decomposition peak temperature of DATNBI is significantly lower than that of TNBI at the same heating rate; its self-accelerating decomposition temperature (50 kg) is only 4 K lower. Therefore, the −NH2group displays good ability of reducing sensitivity but has no influence on storage safety of DATNBI.

In this study, by selecting the carrier injection and transport materials and optimizing the thickness of each functional layer in the device, we have solved the problem of unbalanced carrier injection in quantum dot light‐emitting diodes (QLED). The current efficiencies of red, green and blue spin‐coating QLED devices reach 30 cd/A, 70 cd/A, and 8 cd/A, respectively. By continuous optimization of the ink‐jet printing and film‐forming process, the suitable volume of printed ink drops and drying process conditions are obtained, and completed the fabrication of 55‐inch UHD AMQLED display.

How to chaperone protein drugs into target tumor cells in vivo is a big challenge. Here, we report on small-sized and robust chimaeric vesicles (lipopepsomes) constructed with asymmetric poly(ethylene glycol)-b-poly(α-aminopalmitic acid)-b-poly(l-aspartic acid) triblock copolypeptide as a simple and functional platform for high loading and targeted intracellular delivery of saporin, a protein toxin, in vivo. Cyclic RGD peptide-decorated chimaeric lipopepsomes (cRGD-CLP) following loading 2.0–9.4 wt % of model protein FITC-labeled cytochrome C showed a small hydrodynamic size of 81–86 nm, enhanced internalization by αvβ3-overexpressing A549 lung tumor cells, as well as remarkable accumulation of 7.73% ID/g in the cancerous lung in mice. Saporin-loaded cRGD-CLP displayed a low half-maximal inhibitory concentration of 16.3 nM to A549 cancer cells. Intriguingly, saporin-loaded cRGD-CLP at 16.7 nmol saporin equiv/kg showed a high potency in treating orthotopically xenografted A549 lung tumors, suppressed tumor progression, and remarkably improved survival rate. These chimaeric lipopepsomes provide a versatile and potential means for targeted protein therapy of various malignancies.

A metal‐free oxyboration reaction, in which no acidic proton is involved and no intermediates bearing B−O σ‐bond were observed, was recently reported by the Blum group. Since it showed potential as a general strategy to synthesize heterocyclic boronic esters, understanding the mechanistic details is very important. Two possible pathways of this oxyboration reaction were examined. Moreover, three key processes were highlighted in the pathway, including borylative cyclization, chloride shift, and demethylation. According to the calculations, the early demethylation (which leads to a formal O−B bond) was found to be slightly exergonic, but to have an inaccessible barrier, whereas demethylation after the cyclization step was feasible. The rate‐determining step (RDS) was identified as the intramolecular cyclization for the oxyboration. Further theoretical investigation on the model reaction, in which an indole boronic ester is the product, revealed some interesting differences of reactivity between oxygen and nitrogen. Based on our calculation results, the N−C bond, which is usually treated as inert, can be cleaved in this case. Moreover, the there is a strong tendency for the RDS to shift from cyclization (as observed in the former oxyboration) to demethylation. Experiments were also conducted to confirm the calculations. Theoretical investigations were made to examine the detailed mechanism of ClBcat‐promoted borylative cyclizations toward heterocyclic boronic esters. Three key steps were found through DFT calculations. Further studies on the model reaction indicated that the nucleophilicity of the heteroatom is crucial to the transformation, particularly in the rate‐determining step.

An D–A–D gelator (DTCQ) was designed and synthesized using 2,3-dimethyl-5,8-di(thiophen-2-yl)quinoxaline and N-alkyl 3-aminocarbazole units as acceptor and donor, respectively, which were linked by a single bond. The compound could gelate several solvents, such as benzyl alcohol, aniline, acetophenone, and o-dichlorobenzene, as well as self-assemble into one-dimensional (1D) nanofibers in gel phase. The absorption and infrared spectra of the gels indicated that π–π interactions between aromatic moieties, intermolecular hydrogen bonds between amide units, and van der Waals forces were the driving forces for the formation of 1D self-assemblies and gel. DTCQ gel was red and emits red fluorescence because it has a strong absorption band at 487 nm and an emissive band at 620 nm. Moreover, DTCQ and a fullerene carboxylic acid formed two-component gel, in which the two compounds developed a hydrogen bond complex and self-assembled into 1D nanofibers with closely connected p- and n-channels. The nanofibrous xerogel film can rapidly generate a photocurrent under visible-light radiation through electron transfer from the gelator to fullerene, and then, the excellent exciton separation and charge transfer to two electrodes.

Melt-castable energetic materials are utilized in a wide variety of civilian and military applications, such as construction, demolition, underwater blasting, mining, oil well perforation, and military munitions. 2,4,6-Trinitrotoluene (TNT) is a traditionally-applied melt-castable explosive; however, its low physical-performance output, environmental pollution characteristics, and safety issues restrict its further development towards future industrial applications. This review addresses advances in the design, synthesis, and characterization of new melt-castable energetic materials featuring fluorine, gem-dinitrofluoroethyl, and nitrate ester groups as well as the nitrofurazan and 1,2,4-oxadizaole skeletons, which have led to the development of novel high-performance TNT candidates between 2012 and 2020.