Publications by authors named "Fengfei Xu"

Electrochemical CO reduction (CORR) represents an attractive strategy for achieving carbon neutrality. Nevertheless, developing efficient and inexpensive catalysts is still challenging. Herein, we report a yolk-shell catalyst consisting of Ni nanoparticles (NPs) confined in hierarchical nitrogen-doped carbon nanocages (Ni@hNCNC) for efficient CORR, which demonstrates high CO faradaic efficiency of 98% and impressive CO partial current density of 195 mA cm at -1.

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Atherosclerosis, the primary cause of cardiovascular disease, which has the highest mortality worldwide, is a chronic inflammatory disease mainly induced by excessive lipid accumulation in plaque macrophages. Lipid-laden macrophages are crucial at all stages of atherosclerotic lesion progression and are, thus, regarded as popular therapeutic targets for atherosclerosis. High-density lipoprotein (HDL), an endogenous particle with excellent atherosclerotic plaque-homing properties, is considered a potential therapeutic agent for treating atherosclerosis.

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Targeting the delivery of vaccines to dendritic cells (DCs) is challenging. Here we show that, by mimicking the fast and strong antigen processing and presentation that occurs during the rejection of xenotransplanted tissue, xenogeneic cell membrane-derived vesicles exposing tissue-specific antibodies can be leveraged to deliver peptide antigens and mRNA-encoded antigens to DCs. In mice with murine melanoma and murine thymoma, xenogeneic vesicles encapsulating a tumour-derived antigenic peptide or coated on lipid nanoparticles encapsulating an mRNA coding for a tumour antigen elicited potent tumour-specific T-cell responses that inhibited tumour growth.

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Ammonia synthesis via nitrate electroreduction is more attractive and sustainable than the energy-extensive Haber-Bosch process and intrinsically sluggish nitrogen electroreduction. Herein, we have designed a single-site Cu catalyst on hierarchical nitrogen-doped carbon nanocage support (Cu/hNCNC) for nitrate electroreduction, which achieves an ultrahigh ammonia yield rate (YR) of 99.4 mol h g (2.

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Engineering microstructures of Pt and understanding the related catalytic mechanism are critical to optimizing the performance for hydrogen evolution reaction (HER). Herein, Pt dispersion and coordination are precisely regulated on hierarchical nitrogen-doped carbon nanocages (hNCNCs) by a thermal-driven Pt migration, from edge-hosted Pt-NCl single sites in the initial Pt/hNCNC-70 °C catalyst to Pt clusters/nanoparticles and back to in-plane Pt-NC single sites. Thereinto, Pt-NCl presents the optimal HER activity (6 mV@10 mA cm) while Pt-NC shows poor HER activity (321 mV@10 mA cm) due to their different Pt coordination.

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Adoptive cell therapy (ACT) has shown great success in the clinic for treating hematologic malignancies. However, solid tumor treatment with ACT monotherapy is still challenging, owing to insufficient expansion and rapid exhaustion of adoptive cells, tumor antigen downregulation/loss, and dense tumor extracellular matrix. Delivery strategies for combination cell therapy have great potential to overcome these hurdles.

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Article Synopsis
  • The electrocatalytic nitrate/nitrite reduction reaction (eNORR) can produce ammonia (NH) more effectively than nitrogen reduction but struggles to perform well in neutral electrolytes.
  • Researchers developed a copper catalyst (Cu@hNCNC) using nitrogen-doped carbon nanocages that help maintain a high pH environment, enhancing its performance in neutral settings.
  • This catalyst achieved an impressive ammonia yield rate of 4.0 moles per hour per gram with 99.7% Faradaic efficiency, demonstrating its potential for practical applications without relying on strong alkaline conditions.
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Milk-derived extracellular vesicles (M-EVs) are low-cost, can be prepared in large quantities, and can cross the gastrointestinal barrier for oral administration. However, the composition of milk is complex, and M-EVs obtained by different extraction methods may affect their oral delivery. Based on this, a new method for extracting M-EVs based on cryogenic freezing treatment (Cryo-M-EVs) is proposed and compared with the previously reported acetic acid treatment (Acid-M-EVs) method and the conventional ultracentrifugation method (Ulltr-M-EVs).

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Electrocatalytic CO reduction (CORR) to alcohols offers a promising strategy for converting waste CO into valuable fuels/chemicals but usually requires large overpotentials. Herein, we report a catalyst comprising unique oxygen-bridged Cu binuclear sites (CuOCu-N) with a Cu···Cu distance of 3.0-3.

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Precious-metal single-atom catalysts (SACs), featured by high metal utilization and unique coordination structure for catalysis, demonstrate distinctive performances in the fields of heterogeneous and electrochemical catalysis. Herein, gold SACs are constructed on hierarchical nitrogen-doped carbon nanocages (hNCNC) via a simple impregnation-drying process and first exploited for electrocatalytic carbon dioxide reduction reaction (CORR) to produce syngas. The as-constructed Au SAC exhibits the high mass activity of 3319 A g at -1.

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Renewable-driven electrochemical CO reduction reaction (CORR) to syngas is an encouraging alternative strategy to traditional fossil fuel-based syngas production, and the development of industrial-level electrocatalysts is vital. Herein, based on theoretical optimization of metal species, hierarchical CoNi-N-C dual single-atom catalyst (DSAC) with individual NiN (CO preferential) and CoN (H preferential) moieties was constructed by a two-step pyrolysis route. The CoNi-N-C exhibits a stable CO Faradaic efficiency of 50 ± 5% and an industrial-level current density of 101-365 mA cm in an ultrawide potential window of -0.

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Electrochemical CO reduction reaction (CO RR) to value-added chemicals/fuels is an effective strategy to achieve the carbon neutral. Palladium is the only metal to selectively produce formate via CO RR at near-zero potentials. To reduce cost and improve activity, the high-dispersive Pd nanoparticles on hierarchical N-doped carbon nanocages (Pd/hNCNCs) are constructed by regulating pH in microwave-assisted ethylene glycol reduction.

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Article Synopsis
  • The text discusses the emerging potential of intelligent drug delivery systems that utilize "stimulus-response" mechanisms, particularly through lipid-based nanoparticles.
  • It categorizes signal sources for these systems into two groups: physical stimuli (like temperature and ultrasound) and physiological stimuli (such as pH and redox conditions).
  • The text also outlines how to design drug delivery based on the body's physiological environment, highlights current application methods, and envisions future advancements in this field.
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Nanoparticle-based therapeutics represent potential strategies for treating atherosclerosis; however, the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells. Here, we report reactive oxygen species (ROS)-responsive and size-reducible nanoassemblies, formed by multivalent host-guest interactions between β-cyclodextrins (β-CD)-anchored discoidal recombinant high-density lipoprotein (NP ) and hyaluronic acid-ferrocene (HA-Fc) conjugates. The HA-Fc/NP nanoassemblies have extended blood circulation time, specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium, rapidly disassemble in response to excess ROS in the intimal and release smaller NP , allowing for further plaque penetration, macrophage-targeted cholesterol efflux and drug delivery.

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Macrophage/foam cells and cholesterol crystals (CCs) have been regarded as the central triggers of maladaptive inflammation in atherosclerotic plaque. Despite the tremendous progress of recombinant high-density lipoprotein (rHDL) serving for targeted drug delivery to alleviate inflammation in macrophage/foam cells, the active attempt to modulate/improve its CCs dissolution capacity remains poorly explored. The untreated CCs can seriously aggravate inflammation and threaten plaque stability.

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Correction for 'Supramolecular copolymer modified statin-loaded discoidal rHDLs for atherosclerotic anti-inflammatory therapy by cholesterol efflux and M2 macrophage polarization' by Qiqi Zhang , , 2021, , 6153-6168, DOI: 10.1039/D1BM00610J.

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Venous thromboembolism (VTE) is a prevalent public health issue worldwide. Before treatment, spatiotemporally accurate thrombus detection is essential. However, with the currently available imaging technologies, this is challenging.

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The past decade has witnessed a great progress in cancer immunotherapy with the sequential approvals of therapeutic cancer vaccine, immune checkpoint inhibitor and chimeric antigen receptor (CAR) T cell therapy. However, some hurdles still remain to the wide implementation of cancer immunotherapy, including low immune response, complex tumor heterogeneity, off-target immunotoxicity, poor solid tumor infiltration, and immune evasion-induced treatment tolerance. Owing to changeable physicochemical properties in response to endogenous or exogenous stimuli, nanomaterials hold the remarkable potential in incorporation of multiple agents, efficient biological barrier penetration, precise immunomodulator delivery, and controllable content release for boosting cancer immunotherapy.

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Foam cells with the pro-inflammatory macrophage phenotype (M1) play an essential role in atherosclerosis progression. Either cellular cholesterol removal or drug intervention was reported to polarize M1 into the anti-inflammatory phenotype (M2) for atherosclerosis regression. These might be realized simultaneously by drug-loaded discoidal reconstituted high-density lipoproteins (d-rHDLs) with the functions of cellular cholesterol efflux and targeted drug delivery on macrophages.

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Glioblastoma (GBM) is the most common type of primary central nervous system tumor in adults, which has high mortality and morbidity rates, and short survival time, namely <15 months after the diagnosis and application of standard therapy, which includes surgery, radiation therapy and chemotherapy; thus, novel therapeutic strategies are imperative. The activation of the PI3K/AKT signaling pathway plays an important role in GBM. In the present study, U87 and U251 GBM cells were treated with the PI3K/mTORC1/2 inhibitor PQR309, and its effect on glioma cells was investigated.

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This study aims to investigate the correlation of the photocatalytic oxidation effect of decomposing organic matter and inactivating bacteria using two different TiO2 materials: a Degussa P25 powder film and a commercial TiO2 thin film. The destructed organic matter was formaldehyde and the test bacterium was E. coli (JM 109 strain).

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