Latest ArticlesTwo red-emissive luminogens (TPTH and TPTB) with typical aggregation-induced emission characteristics were developed. By introducing the heavy atom of Br at the end of alkyl chain, TPTB exhibited higher reactive oxygen species generation efficiency through both types Ⅰ and Ⅱ pathways. Due to its excellent biocompatibility and proper lipophilicity, TPTB could be used for long-term cell membrane staining and this staining ability was independent of the change of plasma membrane potential. Furthermore, TPTB could ablate the cancer cells through cell membrane-targeted photodynamic therapy.
In this article, we used the self-excitation and self-inductance characteristics of polyvinylidene fluoride (PVDF) piezoelectric materials, combined with the powerful signal processing and calculation analysis capabilities of integrated circuits, for the first time to explore a set of microcantilever sensor "readout system" without additional driver (self-driving) and can realize self-sensing external signal (self-sensing). It was successfully applied to the unlabeled detection of avian influenza virus (AIV) H9N2. The specific force of the antigen-antibody complexes on the surface of the microcantilever leads to the change of the stress of the cantilever, which drives the constructed detection device, and does not require an additional excitation source to drive it, that is, the self-driving part. At the same time, due to the movement of piezoelectric charges in the film caused by the positive piezoelectric effect of the PVDF film, self-inductive charges are generated on the surface of the sensor dielectric. The charge signal is converted into a voltage signal, and the sensing part is completed, that is, self-sensing. The immunosensor has a linear range of 100-1000 ng/mL with a detection limit of 2.9 ng/mL. The method will also open up a new avenue for the detection of other analytes based on antigen-antibody responses.
Anti-infection and neovascularization at the wound site are two vital factors that accelerate diabetic wound healing. However, for a wound healing dressing, the two functions need to work at different sites (inner and outer), giving big challenges for dressing design. In this study, we fabricated a novel sodium alginate/chitosan (SA/CS) Janus hydrogel dressing by the assembly of SA hydrogel loaded with silver nanoparticles (AgNPs) and CS hydrogel impregnated with l-arginine loaded sodium alginate microspheres (ArgMSs) based on electrostatic interactions to combine the two functions. The outer SA-AgNP hydrogel could prevent infection while avoiding the deposition of AgNPs in the wound site, and the inner CS-ArgMS hydrogel on the wound surface could realize the sustained release of l-arginine and promote vascular regeneration. The composition, morphology and swelling/degradation of the SA-AgNP/CS-ArgMS hydrogel were characterized systematically. l-Arginine release behavior has been tested and SA-AgNP/CS-ArgMS hydrogel has been confirmed for excellent biocompatibility. Antibacterial and angiogenesis assays demonstrated the antibacterial and angiogenesis characteristics of the SA-AgNP/CS-ArgMS hydrogel. Finally, in vivo diabetic wound healing assay demonstrated that the SA-AgNP/CS-ArgMS hydrogel could significantly accelerate re-epithelialization, granulation tissue formation, collagen deposition and angiogenesis, thereby resulting in enhanced diabetic wound healing
Removal and recovery of phosphorus (P) from wastewater is of great importance to addressing the challenges of eutrophication and phosphorus shortage. The P removal and recovery performance of conventional electrochemical precipitation approach was constrained by the limited mass transfer rate. Herein, a cathodic membrane filtration (CMF) reactor was developed using Ti/SnO2-Sb anode and titanium mesh cathodic membrane module to achieve efficient removal and recovery of P in wastewater. Compared with the flow-by mode, the CMF system in the flow-through mode exhibited excellent P removal performance due to the markedly enhanced mass transfer. At the current density of 4 A/m2, membrane flux of 16.6 L m−2 h−1, and Ca/P molar ratio of 1.67, the removal efficiency of P was 96.2% and the energy consumption was only 45.7 kWh/kg P. The local high pH of cathode surface played a vital role in P removal, which substantially accelerated the nucleation of calcium phosphate (CaP). Based on the crystalline and morphological characterization of the precipitates, the hydroxyapatite was the most stable crystalline phase of CaP, which was transformed from intermediate phases (such as dicalcium phosphate and amorphous calcium phosphate). This study paves the way for applying electrochemical membrane filtration system for P removal and recovery from wastewater.
This study reports several modification strategies to optimize and enhance the performance of two-dimensional (2D) metal organic frameworks (MOFs)-derived catalysts in peroxydisulfate (PDS) activation. The raw 2D Ni-MOF and 2D Ni-Fe-MOF without modification show poor catalytic activities for PDS activation and high metal ion leaching. The carbonization of 2D MOF can increase the activity of the catalyst but cannot solve the metal leaching problem. The further acid treatment of carbonization products can further improve the catalytic activity and decrease the metal ion leaching. The in-situ growth of 2D MOF on graphene oxide (GO) support with subsequent carbonization and acid treatment offers the best performance in PDS activation for organic pollutant removal with low metal ion leaching. Compared with other PDS systems, the Ni-Fe-C-acid/GO system displays much lower catalyst and PDS dosages for p-chloroaniline degradation. This study presents new insights in the modification strategies of 2D MOF-based catalysts in PDS activation.
A millimeter scale butterfly-shaped reactor was proposed based on sizing-up strategy and fabricated via femtosecond laser engraving. An improvement of mixing performance and residence time distribution was realized by means of contraction and expansion of the reaction channel. The liquid holdup was greatly increased through connection of multiple mixing units. Structure optimization of the reactor was carried out by computational fluid dynamics simulation, from which the effect of reactor internals on mixing and the influence of parallel branching structure on heat transfer were discussed. The UV–vis absorption spectroscopy was used to determine the residence time distribution in the reactor, and characteristic parameters such as skewness and dimensionless variance were obtained. Further, a chained stagnant flow model was proposed to precisely describe the trailing phenomenon caused by fluid stagnation and laminar flow in small scale reactors, which enables a better fit for the experimental results of the asymmetric residence time distribution. In addition, the heat transfer performance of the reactor was investigated, and the overall heat transfer coefficient was 110–600 W m-2 K-1 in the flow rate range of 10–40 mL/min.
In this paper, cucurbit[7]uril (CB[7])-mediated three-dimensional gold nanoassemblies were successfully prepared to increase the loaded amount of CB[7] and enhance the electrochemical detection of amino acids. Particle sizes of gold nanoparticles (AuNPs) significantly affect stability and detection sensitivity of nanoassemblies. The volume of gold nanoassemblies first increased and then decreased with the increase of CB[7] concentration. The 3D gold nanoassemblies composed of 16 nm AuNPs and 100 µmol/L CB[7] had excellent stability and maximum volume, exhibiting more sensitive detection for a variety of amino acids. And the detection limits of aromatic amino acids are lower in virtue of the higher binding constant between aromatic amino acids and CB[7]. This study will develop and deepen our understanding of molecular recognition in amino acids detection.
Caproate, produced by microbial chain elongation process, is potential to replace the diversified fossil-based products, contributing to carbon neutrality. However, its production performance is far from industrial application, so the cost-effective enhancement measures are highly needed. This study confirmed powdered activated carbon (PAC) has a significant effect on enhancing caproate production performance. The production, yield, and selectivity of caproate were improved by more than 1-fold by the optimized PAC dosage of 15 g/L, comparing with control. Mechanism investigation from a new visual angle showed that PAC accelerated ethanol oxidation to generate acetyl-CoA, and simultaneously boosted the efficiency of reverse β oxidation (RBO) by promoting the timely reaction of butyrate and acetyl-CoA to synthesis caproate. The addition of PAC also shifted the microbial community by enriching more caproate-producing bacteria but eliminating irrelevant ones. Furthermore, metagenomic analysis revealed that PAC effectively up-regulated the functional genes encoding key enzymes responsible for ethanol oxidation and RBO pathway, which was the root cause for the improved caproate production. This study presented the intrinsic insights into the mechanism of PAC promoting caproate generation, laying a foundation to the scale production of caproate.
Liquid chromatography tandem mass spectrometry (LC-MS/MS) plays an important role in clinical diagnostics. Although LC-MS/MS is superior in terms of accurately quantifying molecules in complex matrices, instrument footprint, operation and maintenance complexity also hinder its expansion as the analytical technique of choice. In this study, a compact LC-MS instrument was developed, in which an assembled liquid chromatograph was coupled with a miniature ion trap mass spectrometer. The overall instrument has a footprint of 69 cm × 31 cm × 31 cm, and it requires no gas supply as well as minimum maintenance. Furthermore, the use of LC-MS is in accord with conventional clinical diagnostic protocols, and the choice of ion trap offers tandem MS performance. The results showed that the use of LC could improve both mixture analysis capability and detection sensitivity of the miniature mass spectrometer. After optimization, feasibility of this instrument in clinical practice was demonstrated by the quantitation of four widely used immunosuppressants in blood samples. Relatively good linearities were obtained, which spanned the reference ranges of effective therapeutic concentrations of each immunosuppressant. Intra-day and inter-day accuracy and precision of analytical method were also assessed. This work showed that a compact LC-MS instrument could be used in clinical diagnosis, either to replace conventional lab-scale instruments or to be used in POCT applications.
Metastatic breast cancer (MBC) is one of the most common and knotty diseases in female population which could place them in a life-threatening condition. For malignant proliferation and migration, cancer cells require a large amount of glucose and energy to meet the demand of rapid metabolism. Hence, efficiently diminishing the utilization of energy substances by cancer cells is emerging as validated therapeutic strategies for cancer therapy. Herein, a nanoplatform with dual-inhibition of glucose uptake and oxidative phosphorylation (OXPHOS) was designed, which consisted of albendazole (ABZ) and atovaquone (ATO) by simple carrier-free self-assembling. The introduction of ABZ could evidently decrease glucose uptake to reduce the main "energy fuel" of cancer cells. Meanwhile, as a blocker of OXPHOS, ATO would reduce adenosine triphosphate (ATP) production and ameliorate hypoxia microenvironment by suppressing mitochondrial respiratory chain. Under such dual inhibition of energy metabolism, AA NPs exerted synergistic energy exhaustion effect and outstanding hypoxia improvement function, efficiently inhibiting tumor growth and metastasis. This research not only illustrates the feasibility of energy metabolism therapy by co-inhibiting glucose uptake and OXPHOS, but also provides an ingenious tactic to diminish metastasis during MBC treatment