CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Zimo Lou,Jiasheng Zhou,Mei Sun,Jiang Xu,Kunlun Yang,Dan Lv,Yaping Zhao,Xinhua Xu
A Pd/MnO 2 /Ni foam electrode with hierarchical structure was synthesized via electrodeposition for efficient electrocatalytic hydrodechlorination. Compared with the ordinary Pd/Ni foam electrode, the introduction of MnO 2 greatly enhanced the catalytic reactivity and reduced the dose of precious metal Pd. Only a quarter of Pd was required for the Pd/MnO 2 /Ni foam compared to the Pd/Ni electrode to achieve complete dechlorination of 2,4-dichlorobenzoic acid (2,4-DCBA) within 120 min. Various characterizations suggested that MnO 2 covered the surface of the Ni foam and increased the specific surface area of the electrode, while Pd nanoparticles were subsequently deposited on MnO 2 . The atomic H ∗ -based indirect dechlorination was the dominant pathway while only approximately 13% of 2,4-DCBA was removed by direct electron transfer. Atomic H ∗ adsorbed on Pd acted as the key active species for the dechlorination of 2,4-DCBA by the Pd/MnO 2 /Ni foam electrode in this study. The introduction of MnO 2 would promote the water dissociation and the hydrogen evolution reaction, and provide Pd with more atomic H ∗ . Pd/MnO 2 /Ni foam exhibited good stability and reusability according to the XPS spectra and consecutive electrocatalytic experiments, which suggested its long-term potential for efficient removal of chlorinated contaminants. This work demonstrated a new strategy to design efficient electrocatalysts with less precious metal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Tao Wang,Qiao Yu,Zhilin Chen,Chao Xiao,Shuming Peng
The active phase for methane combustion is still in debate. Low-temperature CO-FTIR spectroscopy was used to probe the working surface state on a series of Pd/Al2O3 (PdAl) and Pd/silicalite-1 (PdSil) catalysts with different starting states: oxidized, reduced (R), reoxidized (Ro). The surface of prereduced PdAl (Pd0) is transformed to an oxidized state (PdOx) with a CO stretching vibration (νCO) at ∼2157 cm–1 when it is aged in the methane oxidation mixture. The aging-induced transformation from Pd0 to PdOx occurred at 250 °C or above. Although PdSil has multiple kinds of PdOx entities, prereduced PdSil also transformed into PdOx. For PdAl(4)-R-A250, XRD patterns suggest weak bulk oxidation of Pd0 at 250 °C, XPS spectra indicate 28% of surface Pd0 atoms are oxidized, but CO-FTIR spectra confirm all the “top surface” Pd0 atoms are oxidized. It demonstrates the advantage of CO-FTIR spectroscopy in probing the top surface state. Finally, a direct correlation between operando FTIR spectroscopy and low-temperature CO-FTIR spectroscopy was established. Operando FTIR spectra over PdSil during methane oxidation at 250 °C gives two bands at 2124 cm–1 (CO–Pd+) and 2161 cm–1 (CO–Pd2+). After cooling in nitrogen, CO-FTIR spectra give two similar bands at 2134 cm–1 and 2157 cm–1. The “working surface state” can be preserved in CO-FTIR. For PdAl(4), operando FTIR spectra at 250 and 300 °C give no bands of adsorbed CO. Adding CO into the methane oxidation mixture resulted in a single CO–Pd2+ band at 2163 cm–1, which is in accord with their CO-FTIR spectra. For operando FTIR spectroscopy, the observation of the bands of adsorbed CO depends on the accumulation of the CO intermediates, but their accumulation is limited to reaction temperatures below 300 °C and to PdSil (not PdAl). These limitations make low-temperature CO-FTIR spectroscopy more general and sensitive.
研究领域:
催化化学
·
材料科学
·
环境化学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2015
·
IF 3.453
Hong Jiang,Qing Yan,Rizhi Chen,Weihong Xing
Pd@ZIF-8 nanoparticles with uniform size and morphology were prepared via an assembly method that enables the crystallization of ZIF-8 in methanol in the presence of polyvinylpyrrolidone (PVP)-modified Pd nanoparticles. The molar ratios of Pd/Zn 2+ and 2-methylimidazole (Hmim)/Zn 2+ are important parameters affecting the physical and catalytic properties of the Pd@ZIF-8. The catalytic activities of the hybrid catalysts were evaluated by the hydrogenation of p -nitrophenol to p -aminophenol. The results indicate that the increase of Pd loading and p -nitrophenol conversion can be tuned by adding more amounts of PVP-Pd colloid, but a suitable amount of PVP-Pd (Pd/Zn 2+ ≤ 0.012) is helpful to the control of particle size of Pd@ZIF-8 and encapsulation of the Pd nanoparticles within the ZIF-8 crystals. Pd@ZIF-8 catalysts prepared with excessive or equal molar of Hmim relative to Zn 2+ have similar morphology and uniform particle size, where the Pd nanoparticles are fully confined within the ZIF-8 crystals without aggregation. Furthermore, the Pd@ZIF-8 catalysts exhibit the better catalytic performance for the p -nitrophenol hydrogenation owing to the high loading of well-dispersed Pd nanoparticles with the decreased Hmim/Zn 2+ molar ratio. This work would aid the development of high-performance Pd@ZIF-8 catalysts.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
BIOMATERIALS
·
2022
·
IF 15.304
Yu-Xiang Ge,Tai-Wei Zhang,Lei Zhou,Wang Ding,Hai-Feng Liang,Zhi-Chao Hu,Qin Chen,Jian Dong,Feng-Feng Xue,Xiao-Fan Yin,Li-Bo Jiang
Poor immunogenicity and compromised T cell infiltration impede the application of immune-checkpoint blockade (ICB) immunotherapy for osteosarcoma (OS). Although autophagy is involved in enhancing the immune response, the synergistic role of autophagy in ICB immunotherapy and the accurate control of autophagy levels in OS remain elusive and challenging. Here, we designed a pH-sensitive autophagy-controlling nanocarrier, [email protected] @PEG-FA (CBZP), loading a natural derivative, curcumin (CUR), to boost the immunotherapeutic response of PD-1/PD-L1 blockade by activating immunogenic cell death (ICD) via autophagic cell death, and BMS1166 to inhibit the PD-1/PD-L1 interaction simultaneously, enhancing the tumor immunogenicity and sensitizing the antitumor T cell immunity. After entering tumor cells, the pH-sensitive nanoparticles induced autophagy and decreased the intracellular pH , which in turn further facilitated the release of CUR to enhance autophagic activity. Transferring CBZP to orthotopic OS tumor-bearing mice showed powerful antitumor effects and established long-term immunity against tumor recurrence, accompanied by enhanced dendritic cell maturation and tumor infiltration of CD8 + T lymphocytes. Collectively, CBZP exhibited synergistic effects in treating OS by combining ICD induction with checkpoint blockade, thereby shedding light on the use of autophagy control as a potential clinical therapy for OS.
研究领域:
肿瘤学
·
免疫疗法
·
纳米技术
·
药理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CONTROLLED RELEASE
·
2023
·
IF 10.8
Xin Yang,Wanqiong Li,Shuzhen Li,Shaomeng Chen,Zheng Hu,Zhuoying He,Xueqin Zhu,Xiaoshuang Niu,Xiuman Zhou,Huihao Li,Youmei Xiao,Juan Liu,Xinghua Sui,Guanyu Chen,Yanfeng Gao
Peptide immune checkpoint inhibitors in cancer immunotherapy have attracted great attention recently, but oral delivery of these peptides remains a huge challenge due to the harsh gastrointestinal environment, large molecular size, high hydrophilic, and poor transmembrane permeability. Here, for the first time, a fish oil-based microemulsion was developed for oral delivery of programmed death-1/programmed cell death-ligand 1 (PD-1/PD-L1) blocking model peptide, OPBP-1. The delivery system was characterized, in vitro and in vivo studies were conducted to evaluate its overall implication. As a result, this nutraceutical microemulsion was easily formed without the need of co-surfactants, and it appeared light yellow, transparent, good flowability with a particle size of 152 ± 0.73 nm, with a sustained drug release manner of 56.45 ± 0.36% over 24 h and a great stability within the harsh intestinal environment. It enhanced intestinal drug uptake and transportation over human intestinal epithelial Caco-2 cells, and drastically elevated the oral peptide bioavailability of 4.1-fold higher than that of OPBP-1 solution. Meanwhile, the mechanism of these dietary droplets permeated over the intestinal enterocytic membrane was found via clathrin and caveolae-mediated endocytic pathways. From the in vivo studies, the microemulsion facilitated the infiltration of CD8 + T lymphocytes in tumors, with increased interferon-γ (IFN-γ) secretion. Thus, it manifested a promising immune anti-tumor effect and significantly inhibited the growth of murine colonic carcinoma (CT26). Furthermore, it was found that the fish oil could induce ferroptosis in tumor cells and exhibited synergistic effect with OPBP-1 for cancer immunotherapy. In conclusion, this fish oil-based formulation demonstrated great potential for oral delivery of peptides with its natural property in reactive oxygen species (ROS)-related ferroptosis of tumor cells, which provides a great platform for functional green oral delivery system in cancer immunotherapy.
研究领域:
药剂学
·
免疫学
·
癌症研究
·
药物递送系统
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
·
2023
·Vol. 21
·期 1
·1-22
·
IF 10.2
Zhang Shushan,Huang Yongquan,Pi Songying,Chen Hui,Ye Feile,Wu Chaoqun,Li Liujun,Ye Qing,Lin Yuhong,Su Zhongzhen
Incomplete radiofrequency ablation (IRFA) triggers mild protective autophagy in residual tumor cells and results in an immunosuppressive microenvironment. This accelerates the recurrence of residual tumors and causes resistance to anti-PD-1/PDL1 therapy, which bringing a great clinical challenge in residual tumors immunotherapy. Mild autophagy activation can promote cancer cell survival while further amplification of autophagy contributes to immunogenic cell death (ICD). To this regard, we constructed active targeting zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (NPs) loaded with STF62247 or both STF62247 and BMS202, namely STF62247@ZIF-8/PEG-FA (SZP) or STF62247-BMS202@ZIF-8/PEG-FA (SBZP) NPs. We found that SZP NPs inhibited proliferation and stimulated apoptosis of residual tumor cells exposed to sublethal heat stress in an autophagy-dependent manner. Further results discovered that SZP NPs could amplify autophagy in residual tumor cells and evoke their ICD, which dramatically boosted the maturation of dendritic cells (DCs). Through vaccination experiments, we found for the first time that vaccination with heat + SZP treatment could efficiently suppress the growth of new tumors and establish long-term immunological memory. Furthermore, SBZP NPs could remarkably promote the ICD of residual tumor cells, obviously activate the anti-tumor immune microenvironment, and significantly inhibit the growth of residual tumors. Thus, amplified autophagy coupled with anti-PD-1/PDL1 therapy is potentially a novel strategy for treating residual tumors after IRFA.Graphical Abstract
研究领域:
肿瘤学
·
免疫治疗
·
纳米技术
·
癌症生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Yueshan Xu,Daoxiong Wu,Peilin Deng,Jing Li,Junming Luo,Qi Chen,Wei Huang,Chong Michael Shim,Chunman Jia,Zhongxin Liu,Yijun Shen,Xinlong Tian
The direct methane (CH 4 ) oxidation to high value-added C1 chemicals is a great promising strategy to explore the CH 4 resource utilization. However, the low activity and selectivity of catalytic performance remains a great conundrum due to the difficulty to activate the C H bond and the unmanageable over oxidation. Herein, Pd x Au y nanowires (NWs) with various Pd/Au atomic ratios are presented as ideal models to explore the atomic-level effect of PdAu atoms for the direct CH 4 oxidation. The influence of reaction parameters are systematically investigated, and Pd 9 Au 1 NWs display a maximum yield of 2890.3 μmol g −1 h −1 with 99% selectivity for the liquid C1 oxygenated products. This enhanced performance is attributed to the combination of one-dimensional structure and the synergistic effect from the suitable portion of Au on Pd sites, which regulates bond strength between adsorbed radicals (•OH, •OOH, •CH 3 ) and PdAu atoms, confirmed by the density function theory calculations.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Tao Ma,Feng Liang
Bimetallic nanoparticles consisting of gold (Au) and palladium (Pd) have attracted considerable attention because of their effective catalysis for many chemical reactions. They are highly expected to help in the preparation of Au–Pd nanocatalysts with a controllable structure, morphology, and composition. Here, we show that Au–Pd nanostars (NSs) with tunable surface plasmon resonance absorption (from 536 to 583 nm), nanoparticle size, and palladium content (less than 7 wt %) can be obtained by adjusting the ratio of ascorbic acid and chloroauric acid. These synthesized Au–Pd NSs could be utilized efficiently for the reduction of 4-nitrophenol and nitrobenzene and the Suzuki coupling reaction. Their enhanced catalytic activity could be due to their easy accessibility of the active sites, star-like structure, and Pd-rich surface. The systematic synthesis reported in this work will not only give researchers new insights into the controllable preparation of bimetallic nanoparticles but may also inspire further studies of multifunctional nanocatalysts.
研究领域:
材料科学
·
催化化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Electrocatalysis
·
2014
·Vol. 6
·期 3
·255-262
·
IF 2.089
Lu Hai-Ting,Yang Zi-Juan,Yang Xin,Fan Yang
CeO 2 nanotubes with well-defined hollow interiors are employed as support material for Pd electrocatalysts towards formic acid oxidation (FAO). Pd nanoparticles are deposited both on the outer surfaces and inside interiors of CeO 2 nanotubes. The as-prepared Pd catalysts possess a large electrochemical surface area (ESA) and exhibit improved electrocatalytic performance towards FAO in comparison with the Vulcan XC-72 carbon black and the commercial CeO 2 powder supported Pd catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
International Journal of Nanomedicine
·
2024
·
IF 6.6
Haishui Sun,Xiao Wang,Zhaoyang Guo,Zhenrong Hu,Yuanchen Yin,Shuhan Duan,Wenwen Jia,Wei Lu,Jingzhou Hu
Introduction Traditional surgical resection, radiotherapy, and chemotherapy have been the treatment options for patients with head and neck squamous cell carcinoma (HNSCC) over the past few decades. Nevertheless, the five-year survival rate for patients has remained essentially unchanged, and research into treatments has been relatively stagnant. The combined application of photothermal therapy (PTT) and immunotherapy for treating HNSCC has considerable potential.Methods Live-dead cell staining and CCK-8 assays proved that Fe3O4 nanoparticles are biocompatible in vitro. In vitro, cellular experiments utilized flow cytometry and immunofluorescence staining to verify the effect of Fe3O4 nanoparticles on the polarisation of tumor-associated macrophages. In vivo, animal experiments were conducted to assess the inhibitory effect of Fe3O4 nanoparticles on tumor proliferation under the photothermal effect in conjunction with BMS-1. Tumour tissue sections were stained to observe the effects of apoptosis and the inhibition of tumor cell proliferation. The histological damage to animal organs was analyzed by hematoxylin and eosin (H&E) staining.Results The stable photothermal properties of Fe3O4 nanoparticles were validated by in vitro cellular and in vivo animal experiments. Fe3O4 photothermal action not only directly triggered immunogenic cell death (ICD) and enhanced the immunogenicity of the tumor microenvironment but also regulated the expression of tumor-associated macrophages (TAMs), up-regulating CD86 and down-regulating CD206 to inhibit tumor growth. The PD-1/PD-L1 inhibitor promoted tumor suppression, and reduced tumor recurrence and metastasis. In vivo studies demonstrated that the photothermal action exhibited a synergistic effect when combined with immunotherapy, resulting in significant suppression of primary tumors and an extension of survival.Conclusion In this study, we applied Fe3O4 photothermolysis in a biomedical context, combining photothermolysis with immunotherapy, exploring a novel pathway for treating HNSCC and providing a new strategy for effectively treating HNSCC.
研究领域:
癌症生物学
·
纳米技术
·
免疫疗法
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 18
·8739-8751
·
IF 3.925
Quansheng Wu,Songhua Zhou,Chengbing Fu,Jiesong Zhang,Bo Chen,Hongyan Pan,Qian Lin
For the mono-metal Pd based catalysts, the O–O bond in O2 and H2O2 is easily dissociated due to the higher energy sites of Pd, which decreases the selectivity and productivity of H2O2. To address this issue, non-noble metals M (M = Sn, Fe, Co, Ni) were doped into palladium precursors to create a series of yolk–shell structure bimetallic catalysts Pd–M@HCS (H = hollow; C = carbon; S = sphere) with Pd–M as the core and porous carbon as the shell. The results indicated that the catalyst Pd–M@HCS doped with Sn, Fe, Co, and Ni has a weak dissociation ability for O2, and both the adsorption and dissociation ability for H2 are improved. Of these catalysts, the catalyst Pd–Sn@HCS gives the best performance, which is benefited by the suitable Pd–Sn nanoparticle size and the best Pd2+/Pd0 ratio. The influence of the nPd/nSn ratio in the Pd–Sn@HCS system on catalyst performance was further explored, and the findings revealed that Pd–Sn@HCS had the best catalytic activity and stability when the nPd/nSn ratio was 2. The catalyst's H2 conversion, H2O2 selectivity, and productivity were 35%, 97%, and 3961 mmol gPd−1 h−1, respectively. After 10 cycles, the H2O2 productivity of this catalyst remained at 92.1%, which was greater than the H2O2 productivity of the typical Pd-based catalyst Pd/C, which stayed at 37% under the same conditions.
研究领域:
催化
·
化学工程
·
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2020
·
IF 3.687
Yaqi Qu,Yan Wang,Jianwei Li,Qiuxia Xu,Xin Liang,Angran Jiang
CO coupling to dimethyl oxalate (DMO) has been considered as the most important part in industrial production of ethylene glycol (EG). Five kinds of Pd nanoparticles with various morphologies were successfully synthesized by liquid-phase reduction. The exposed crystal planes of these Pd nanoparticles were identified and quantified. The corresponding supported Pd/α-Al 2 O 3 showed excellent catalytic activities for CO coupling reaction and the catalysts including Pd icosahedra can enhanced the selectivity of DMO to 98% and remained unchanged for 50 hours. The characterization results illustrated that the exposure of Pd (111) facets enhanced the intensities of bridged CO, which contributed to the high performance of the Pd-based catalysts. DFT calculations revealed CO adsorbed on Pd (111) facets had higher binding energies. This work systematically discussed the influence of Pd morphologies. Experimental and theoretical results confirmed that the Pd (111) facets showed better catalytic activities for CO coupling reaction.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）