查找使用阿拉丁产品的科研文献

Enhanced recovery of germanium(IV) from zinc residue leachate by tartaric acid functionalized chitosan: Experiments and DFT calculation

Hongrui Xiang,Zhihui Yang,Xiaobo Min,Yanjie Liang,Cong Peng,Xiaoyun Liu,Rui Yuan,Qingwei Wang,Feiping Zhao

The recovery of germanium (Ge) from zinc residue leachate has attracted increasing attention. Herein, this study report on the development of a tartaric acid functionalized chitosan (TA-CS) material serving as an efficient adsorbent for Ge(IV). The introduction of TA resulted in abundant protonatable hydroxyl and carboxyl groups , which endows materials with excellent buffering capacity under acidic conditions. Adsorption kinetics and isotherms showed a fast and efficient adsorption capacity of 57.28 mg/g for Ge(IV). In binary systems, Ge(IV) was preferentially adsorbed over Zn(II), a major coexisting ion, with a separation factor of 3.22. The SEM–EDS FT-IR, XPS and DFT results revealed that mechanisms in combination, including electrostatic adsorption, complexation, hydrogen bonding, and ion exchange, promoted the immobilization of Ge(IV) on TA. The TA-CS material also exhibited great reusability with an adsorption efficiency of 70% after 3 recycles. For the recovery of Ge(IV) in practical zinc residue leachate, the TA-CS material showed superior affinity toward Ge(IV) and a 10-fold higher of adsorption capacity compared to that of pristine chitosan. Together, TA-CS demonstrates that it is a viable and economical material for the separation and preconcentration of Ge(IV) from zinc residue leachate.

Rapid colorimetric sensor for ultrasensitive and highly selective detection of Fumonisin B1 in cereal based on laccase-mimicking activity of silver phosphate nanoparticles

Xiaojuan Niu,Huanhuan He,Hang Ran,Zhen Wu,Yue Tang,Yuangen Wu

Ag 3 PO 4 nanoparticles (NPs) was prepared through a facile coprecipitation method, and was first found to have excellent laccase-mimicking catalytic activity. The study confirms that Fumonisin B1 (FB1) can effectively hinder the production of superoxide anion (O 2 − ) between Ag 3 PO 4 NPs and dissolved oxygen, and further inhibit laccase-mimicking activity of Ag 3 PO 4 NPs. Thus, a novel rapid colorimetric sensor for FB1 analysis in cereal was first established using laccase-mimicking activity as sensing signal. The absorbance variation of sensing solution is directly related to the amount of FB1, and the color change is further combined with smartphone for quantitively analysis of FB1. The limit of detection (LOD) of the sensor is determined as low as 1.73 μg·L −1 , which is far lower than the maximum residue limits (MRLs) of FB1 set by European Commission and US Food and Drug Administration (FDA). The average recovery of 87.8–104.5% for FB1 detection was obtained in cereal.

Tumor Microenvironment Mediated Spermidine-Metal-Immunopeptide Nanocomplex for Boosting Ferroptotic Immunotherapy of Lymphoma

Tianqi Nie,Hengyu Liu,Zhengwen Fang,Yilu Zheng,Ruhe Zhang,Xiaojun Xu,Sixi Liu,Jun Wu

Immunotherapy as an alternative treatment strategy for B-cell lymphoma is undesirable because of tumor heterogeneity and immune surveillance. Spermidine (SPM), as a regulator of the tumor microenvironment (TME), can facilitate the release of damage-associated molecular patterns (DAMPs) from cancer cells, promote immune recognition, and thus alleviate immune surveillance in the TME. Hence, in this work, self-assembled spermidine-based metal-immunopeptide nanocomplexes (APP-Fe NCs; APP is anti-programmed death ligand-1 peptide) with pH-responsive release kinetics were prepared via the flash nanocomplexation (FNC) technique based on the noncovalent interaction between APP-SPM-dextran (DEX) and sodium tripolyphosphate (TPP) and coordination between Fe3+ and TPP. An in vitro study suggested that APP-Fe NCs effectively induce strong oxidative stress and mitochondrial dysfunction and subsequently lead to ferroptosis in cells by interfering with homeostasis in lymphoma cells. Further investigation on lymphoma mice models demonstrated that APP-Fe NCs effectively inhibited the growth and liver metastasis of lymphomas. Mechanistically, by triggering ferroptosis in tumor tissues, these spermidine-containing APP-Fe NCs efficiently facilitated the release of DAMPs and ultimately reshaped TME to enhance immunotherapy efficacy in lymphoma. Combined with its good histocompatibility and facile preparation technique, this pH-responsive APP-Fe NCs with regulation on TME may hold potential for cascade amplification on the combinative immunotherapy of lymphoma in the clinic.

Xylenol orange-modified CdTe quantum dots as a fluorescent/colorimetric dual-modal probe for anthrax biomarker based on competitive coordination

Yatian Cao,Xiaolong Gong,Le Li,Huihui Li,Xuanming Zhang,Dong-Yu Guo,Fuxiang Wang,Qinhe Pan

Bacillus anthracis spores can make humans infected with vicious anthrax, so it is significant to detect their biomarker 2,6-pyridinedicarboxylic acid (DPA). The development of dual-modal methods for DPA detection that are more flexible in practical applications remains a challenge. Herein, colorimetric xylenol orange (XO) was modified on fluorescent CdTe quantum dots (QDs) for dual-modal detection of DPA through competitive coordination. After the binding of XO on CdTe QDs via coordination with Cd 2+ , CdTe QDs displayed quenched red fluorescence and the bound XO was presented as red color. The competitive coordination of DPA with Cd 2+ made XO released from CdTe QDs, causing the enhanced red fluorescence of CdTe QDs and the yellow color of free XO. On this basis, DPA was rapidly (1 min) quantified through fluorescent and colorimetric modes within the ranges of 0.1–5 μM and 0.5–40 μM, respectively. The detection limits for DPA were calculated as low as 42 nM and 240 nM, respectively assigned to fluorescent and colorimetric modes. The level of urinary DPA was further measured. Satisfactory relative standard deviations (fluorescent mode: 0.1%–10.2%, colorimetric mode: 0.8%–1.8%) and spiked recoveries (fluorescent mode: 100.0%–115.0%, colorimetric mode: 86.0%–96.6%) were obtained.

Antibacterial properties of citral against Staphylococcus aureus: From membrane damage to metabolic inhibition

Jinming Dai,Mei Bai,Changzhu Li,Wai San Cheang,Haiying Cui,Lin Lin

Citral, a natural antimicrobial agent, has been found to induce severe membrane damage resulting in bacterial death. Despite its effectiveness, there is a lack of in-depth research on its interaction with bacterial cells, especially at low concentrations. This work aimed to investigate the impact of citral concentration on its antibacterial effect against Staphylococcus aureus ( S. aureus ) and to analyze the relevance between membrane damage and cell death. In this study, the minimal inhibitory concentration of citral against S. aureus was measured at 0.25 mg/mL. At a concentration of 0.5 mg/mL, citral significantly disturbed the cell membrane fluidity and permeability, leading to the leakage of intracellular macromolecules and rapid cell death. However, when the concentration was decreased to 0.25 mg/mL, the membrane damage was greatly reduced, and a complex biological process between citral and membrane components was found. Under continuous drug exposure, the cell membrane underwent gradual rigidification, concomitant with the loss of membrane function, ultimately causing cell death. Despite the fact that no notable disturbance to membrane functions was discovered, the presence of 0.125 mg/mL citral could still weaken the metabolic vitality and growth of S. aureus . Therefore, it was suggested that there could be multiple mechanisms of citral action on S. aureus cells, with drug concentration being a critical factor affecting the mode of action. Overall, the findings of this study provide valuable insights into the antibacterial mechanisms of natural compounds and broaden the potential applications of citral as a natural antimicrobial.

Codelivery of TRAIL and Mitomycin C via Liposomes Shows Improved Antitumor Effect on TRAIL-Resistant Tumors

Rui Chang,Rongrong Fu,Yujiao Huang,Jibing Zhang,Changshun Feng,Rui Wang,Hui Yan,Guangyong Li,Xiaohong Chu,Fengjiao Yuan,Dianlong Jia,Jun Li

Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) constitutes a promising antitumor drug, tumor resistance to TRAIL has become a major obstacle in its clinical application. Mitomycin C (MMC) is an effective TRAIL-resistant tumor sensitizer, which indicates a potential utility of combination therapy. However, the efficacy of this combination therapy is limited owing to its short half-life and the cumulative toxicity of MMC. To address these issues, we successfully developed a multifunctional liposome (MTLPs) with human TRAIL protein on the surface and MMC encapsulated in the internal aqueous phase to codeliver TRAIL and MMC. MTLPs are uniform spherical particles that exhibit efficient cellular uptake by HT-29 TRAIL-resistant tumor cells, thereby inducing a stronger killing effect compared with control groups. In vivo assays revealed that MTLPs efficiently accumulated in tumors and safely achieved 97.8% tumor suppression via the synergistic effect of TRAIL and MMC in an HT-29 tumor xenograft model while ensuring biosafety. These results suggest that the liposomal codelivery of TRAIL and MMC provides a novel approach to overcome TRAIL-resistant tumors.

Conductive black carbon promoted biotransformation of undissolved 2, 2′-dinitrobiphenyl by mediating electron transfer

Hefei Wang,Zeming Wang,Jibao Deng,Jian Wang,Yanzheng Gao

With low bioaccessbility, persistence of the undissolved organic pollutants in soil and sediments poses threat to health of the resident. Although ubiquitous black carbon catalyzes a wide range of biogeochemical reactions in nature, its role in biotransformation of the compounds in non-aqueous phase like 2, 2′-nitrobiphenyl remains unclear. Reduction rate constants of 2, 2′-dinitrobiphenyl by Shewanella oneidensis MR-1 increased from 0.0044 h −1 by 7-fold to 0.035 h −1 in the presence of black carbons produced at pyrolysis temperature of 250–900 °C. Accordingly, electrical conductivity of black carbon was enhanced from 0 to 5.56 S∙cm −1 . The reactivity of black carbon for catalyzing the biotransformation positively correlated with its electrical conductivity ( R 2  > 0.89), which was strongly associated with conductive graphitic clusters in it. The surface oxygenated groups in black carbon were likely not involved in the bioreduction. This work attaches importance to role of the ubiquitous black carbon in natural biotransformation of the undissolved pollutants, and elucidates new mechanism for the biotransformation.

One-pot synthesis of a peroxidase-like nanozyme and its application in visual assay for tyrosinase activity

Shuangqin Li,Di Liu,Bingyan Wu,Huipeng Sun,Xiaoyan Liu,Haixia Zhang,Nana Ding,Lan Wu

Both single-atom nanozymes (SAzymes) and protein-template metal nanoparticles have attracted comprehensive attention in several respects owing to their excellent catalytic performance, green facile synthesis process, and robustness. Herein, the peroxidase-like activity of single-atom copper anchored on bovine hemoglobin-template gadolinium nanoparticles (Cu, [email protected] FITC NPs) were successfully synthesized and two sensitive turn-on fluorescence strategies for tyrosinase (TYR) activity sensing were proposed for the first time. For strategy Ⅰ, TYR sensing was carried out from 1.00 to 7.80 U/mL with the detection limit (LOD) of 0.20 U/mL based on the fluorescence resonance energy transfer (FRET) between the fluorescein isothiocyanate (FITC) and the in situ generated polydopamine dots (PDA-dots). For strategy Ⅱ, The LOD of TYR was 0.05 U/mL with the linear range of 0.40–19.70 U/mL based on the elimination of inner-filter effect (IEF) between FITC and the reaction product (RC) of phenol and 4-Aminoantipyrine (AAP). The smartphone-assisted sensing platform was applied to construct the on-site detection of TYR with both strategies. The developed probe possessed good selectivity and was successfully utilized to TYR detection in serum samples.

Depression and anxiety in patients with active ulcerative colitis: crosstalk of gut microbiota, metabolomics and proteomics

Xiaomin Yuan,Biqing Chen,Zhenglan Duan,Ziqian Xia,Yang Ding,Tuo Chen,Huize Liu,Baosheng Wang,Bolin Yang,Xiaoyong Wang,Shijia Liu,Jin-Yong Zhou,Yajun Liu,Qiong Wang,Zhaofeng Shen,Jun Xiao,Hongtao Shang,Weiwei Liu,Guoping Shi,Lei Zhu,Yugen Chen

Preparation of covalently bonded liposome capillary column and its application in evaluation of drug membrane permeability

Hui Jiang,Shi-Jun Yin,Xu Wang,Min Lu,Hao Zhang,Feng-Qing Yang

Two liposomes , including 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) + 1,2-dimyristoyl- sn -glycero-3-phosphoethanolamine (PE) + cholesterol (Chol) (DSPC/PE/Chol liposomes) and soybean lecithin (SPC) + PE + Chol (SPC/PE/Chol liposomes), were prepared and fixed on the inner wall of capillary column by using the adhesion of polydopamine (PDA) membrane and the cross-linking property of glutaraldehyde (GA). The immobilized liposome capillary column (ILCC) has good repeatability and stability based on the electrophoretic mobility of analyte . A CE method based on the immobilized liposome capillary column chromatography (ILCCC) was successfully developed to study the retention behavior of drugs on ILCC, and the logarithm of retention factor (log k ) of neutral and ionic drugs were determined. The results show that the log k measured by the ILCCC based on two liposomes have a good linear fitting (R 2 = 0.86). Moreover, the linear relationship between ILCCC system and other related research systems (octanol-water system and immobilized artificial membrane (IAM)) was analyzed, and the results indicate that SPC/PE/Chol ILCCC, DSPC/PE/Chol ILCCC and IAM systems have good fitting results, R 2 values are 0.86 and 0.78, respectively. In addition, the normalization coefficients of ILCCC and IAM systems obtained by the linear free energy relationship (LFER) analysis are close and the d value is small. In short, the ILCCC is a simple and feasible method for studying drug membrane permeability.

Sodium Alginate Hydrogel-Mediated Cancer Immunotherapy for Postoperative In Situ Recurrence and Metastasis

Yingying Zhang,Tiange Wang,Yinping Zhuang,Tiandi He,Xiaoli Wu,Lin Su,Jun Kang,Jin Chang,Hanjie Wang

With the development of technology, adjuvant immunotherapy has become a promising strategy for prevention of postoperative tumor regression and metastasis by stimulating the host immune response. However, the therapeutic effects are still unsatisfactory due to the lack of synergy between different methods. In this study, an efficient synergistic immunotherapy system based on injectable sodium alginate hydrogels was designed to inhibit in situ recurrence and metastasis at the same time. On the one hand, an injectable sodium alginate (SA) hydrogel microsystem loaded with toll-like receptor (TLR) agonists (CpG ODNs) was synthesized for inhibiting in situ recurrence, and then carcinoembryonic antigen (CEA) probe was also added to detect CEA based on fluorescence resonance energy transfer (FRET) technology to monitor the occurrence and development of tumor recurrence. On the other hand, an anti-programmed cell death 1 ligand 1 antibody (anti-PD-L1)-modified SA nanogel loaded with indocyanine green (ICG@SA-anti-PD-L1 nanogel) was prepared for diagnosing and inhibiting lung metastasis by assisting orthotopic tumor therapy. In vitro and in vivo results demonstrated that this SA micro/nanosystem could monitor and inhibit postoperative recurrence and metastasis. We hope that this micro/nano-synergistic system will become an effective strategy for postoperative adjuvant immunotherapy.

Smart iron-based metal–organic framework nanovehicles gated with CuII-tannic acid coordination polymers for combination therapy of chemotherapy and chemodynamic therapy

Jiangtao Dong,Tongtong Li,Hua Yan,Yuxia Chen,Chen Wang,Xingkun Luan,Xiaona Li,Hang Li,Xuezhong Du

Smart iron-based metal–organic framework MIL-101(Fe III ) nanovehicles gated with Cu II -tannic acid (TA) coordination polymers were constructed via “on site” self-assembly. The controlled release of antitumor drugs encapsulated within MIL-101(Fe III ) mesopores was realized in response to the tumor microenvironments [such as low pH, glutathione (GSH), H 2 O 2 , and adenosine-5’-triphosphate (ATP)] and near infrared light, due to the photothermal effect of the nanocarriers , by the disassembly of the Cu II -TA gating films and/or the degradation of the MIL-101(Fe III ) nanocarriers. The low pH gave rise to the disassembly of the Cu II -TA gating films and the release of drugs. The competitive coordination of ATP with Cu II /Fe III caused the disassembly of the Cu II -TA gating films, the degradation of the nanocarriers, and the release of drugs. The overexpressed GSH could reduce Cu II /Fe III to Cu I /Fe II and resulted in the disassembly of the Cu II -TA gating films and the degradation of the nanocarriers, and the produced Cu I /Fe II could catalyze H 2 O 2 of elevated level to generate more hydroxyl radicals via the Fenton/Fenton-like reactions for cell apoptosis. The cascade reactions of the depletion of GSH and the generation of hydroxyl radicals based on the gated nanovehicles achieved chemodynamic therapy (CDT) besides chemotherapy. The smart nanovehicles have promising applications in combination tumor therapy of chemotherapy and CDT.