Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Wanzhu Wang,Xuhan Ge,Daqing Chen,Lichao Wu,Danhua Ge,Xiaojun Chen
In contrast to peroxidase-mimicking nanozymes, oxidase mimics directly employ molecular oxygen (O 2 ) as oxidant to generate reactive oxygen species (ROS). Generally, transition metal-based nanozymes exhibit poor oxidase-like activity. We herein constructed a colorimetric sensor based on Co-based oxidase mimic, where the Co nanoparticles were encapsulated in hollow N-doped carbon nanospheres (Co-N/C). Co nanoparticles confined catalyst effectively anchored the active part, which greatly influenced the catalytic activity of the oxidase-mimic nanozymes. Due to the antioxidative property of L-Cysteine (L-Cys) and the specific complexation between L-Cys and Hg 2+ , the rationally designed Co-N/C could be utilized to detect L-Cys and Hg 2+ . The proposed sensing platform exhibited wide linear ranges of 1–30 μM for L-Cys and 0.6–30 μM for Hg 2+ , respectively. The excellent selectivity of the constructed sensor showed the reliability and practicality for the assay of L-Cys and Hg 2+ in fetal bovine serum. The spatial confinement can prevent the aggregation of Co nanoparticles, boosting the stability and catalytic performance in colorimetric sensing.
✓ 已验证
产品关联
DOI
高影响因子
Food & Function
·
2016
·Vol. 7
·期 5
·2398-2408
·
IF 2.686
Xiaofei Li,Jian Li,Zhike Li,Ying Sang,Yunhui Niu,Qianying Zhang,Hong Ding,Shanye Yin
Despite major scientific advances in its prevention, treatment and care, hypertension remains a serious condition that might lead to long-term complications such as heart disease and stroke. The great majority of forms of hypertension eventually result from an increased vasomotor tone activity that is regulated by endothelial NOS (eNOS) in vascular endothelium. Here, we examined the effect of fucoidan on eNOS activation in human umbilical vein endothelial cells (HUVECs). We also examined the effects of functional components of Undaria pinnatifida fucoidan on blood pressure and vascular function in eNOS inhibition-induced hypertensive rats in vivo. Our results suggest that fucoidan increased nitric oxide production by activating eNOS and Akt phosphorylation, which could be impaired by Akt or eNOS inhibitors. In the hypertensive rat model, treatment of fucoidan resulted in potent and persistent reduction of high blood pressure (BP) even after drug withdrawal. Our results showed that the mechanisms might involve protection against vascular structure damage, enhanced endothelium-independent vascular function and inhibition of abnormal proliferation of smooth muscle cells, which are mediated by the Akt–eNOS signaling pathway. Moreover, fucoidan treatment reduced the vascular inflammation and oxidative stress control caused by iNOS expression. Together, these results support a putative role of fucoidan in hypertension prevention and treatment.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 21
·
IF 1.86
Xiaoya Jiang,Xiaoyan Jiao,Doudou Zhang,Ligai Bai,Haiyan Liu,Hongyuan Yan
A polymer monolithic column was prepared via redox system in a stainless steel column (50 × 4.6 mm i.d.) by using 1,6-hexanediol diacrylate as monomer and ethylene dimethacrylate as cross linking agent. Characteristics of the homemade monolithic column were investigated by scanning electron microscopy, nitrogen adsorption-desorption and mercury intrusion porosimeter, respectively. The results showed that the resulting monolithic column occupied relative uniform porous skeleton structure. Furthermore, the monolith was tested by separating aromatic compounds in conjunction of high performance liquid chromatography with the highest column efficiency of more than 21,000 plate per meter, which was relative high for polymer-based monolithic column with 4.6 mm i.d. At last, the monolithic column was used to simultaneously separate and quantitatively analyzes five active compounds in Chinese herb Rheum palmatum L. The validation of the method was carried out, which indicated that the accuracy represented by recovery was in the range of 98.48% to 101.57%. Limit of detection and limit of quantification for the five active compounds were less than 33.7 ng and 90.8 ng, respectively. All the results indicated that the present method was simple and efficient for quantitative analysis of the five active compounds from Chinese herb Rheum palmatum L. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44874.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2016
·Vol. 41
·期 4
·e12999
·
IF 0.894
Chuying Chen,Xuan Peng,Rong Zeng,Chunpeng Wan,Ming Chen,Jinyin Chen
A novel edible coating based on carboxymethyl cellulose (1.5%, CMC) containing ethanol extract of Impatiens balsamina L. stems, 0.07% citric acid, 0.5% sucrose ester, 1.0% calcium propionate and 0.5% glycerol was applied to “Xinyu” tangerines to delay their ripening and prolong postharvest life during storage at 5C for 100 days. The addition of IB extract as antifungal components in the CMC coating had an inhibitory effect on mold growth, and the coated treatments significantly decreased decay rate and weight loss, maintained commercial quality and enhanced the activities of antioxidant and defense-related enzymes compared with the uncoated control group. The results suggested that by applying the complex coating, we can delay the ripening and prolong the postharvest life of “Xinyu” tangerines. Practical Applications Edible coatings could be an effective technology for obstructing pathogenic infection and delaying the ripening process of fruits and vegetables during the postharvest storage period. The effectiveness of an edible coating based on 1.5% CMC coating containing IB extract and other film-forming additives, in comparison with CMC coating without IB extract, was applied in “Xinyu” tangerines in order to reduce the rate of decay and maintain the nutritional quality of fruit during postharvest storage. The results showed that complex coating was able to provide a barrier to the pathogen and gas by reducing decay rate and weight loss. Meanwhile, the degradation of the nutritional quality of “Xinyu” tangerines was significantly delayed. The activities of SOD, CAT, POD, PAL and GLU were much higher in the complex coating treatment than in CMC coating alone and the control group. Our results suggest that the complex coating could be explored as a novel and potentially natural edible coating for preserving “Xinyu” tangerines.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 74
·70243-70250
·
IF 3.289
Xiaohui Fu,Yinan Ma,Jing Sun,Zhibo Li
A series of poly(L-glutamate) bearing Y-shaped oligo(ethylene glycol)x (OEGx) side-chains (PPLG-g-EGx, x = 2, 3 and 4) were synthesized via a combination of ring opening polymerization (ROP) of γ-propargyl-L-glutamate N-carboxyanhydride (PLG-NCA) with thiol–yne photoaddition. The solubility of the polypeptides in water was firstly investigated. PPLG-g-EG3 and PPLG-g-EG4 were soluble in water and displayed fully reversible thermal-responsive behaviors. Additionally, the polypeptides showed redox-responsive properties along with the conformation associated water solubility due to the presence of thioether groups in the side-chains. In particular, the clouding points (CPs) of the polypeptides are highly tunable depending on the degree of polymerization (DP), the side-chain length, the polymer/salt concentration, and the degree of oxidation/reduction. The key feature of our design is the simultaneous incorporation of thermal-responsive OEG units and redox-responsive thioether linkages by one-step thiol–yne photoaddition, which allows for precisely tuning the phase transition temperature by both stimuli. This synthetic approach offers a facile and efficient way to prepare polypeptide-based biomaterials with highly tunable properties.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2016
·
IF 2.857
Guang Wang,Hong Zhang,Furao Lai,Hui Wu
Selenite can enhance the selenium nutrition level of crops, but excessive selenite may be toxic to plant growth. To elucidate the mechanisms underlying the role of selenite in production and detoxification of oxidative toxicity, peanut seedlings were developed with sodium selenite (0, 3, and 6 mg/L). The effects of selenite on antioxidant capacity, transcript levels of antioxidant enzyme genes, and enzyme activities in hypocotyl were investigated. The CuZn-SOD, GSH-Px, GST, and APX gene expression levels and their enzyme activities in selenite treatments were 1.0–3.6-fold of the control. Selenite also significantly increased the glutathione and ascorbate concentrations by mediating the ascorbate–glutathione cycle, and the selenite-induced hydrogen peroxide may act as a second messenger in the signaling pathways. This work has revealed a complex antioxidative response to selenite in peanut seedling. Understanding these mechanisms may help future research in increasing selenite tolerance and selenium accumulation in peanut and other crops.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PLoS One
·
2016
·Vol. 11
·期 9
·e0161566
·
IF 3.057
Ming Guo,Xiaomeng Wang,Xiaowang Lu,Hongzheng Wang,Peter E. Brodelius
In order to obtain the biological active compound, α-mangostin, from the traditional native mangosteen ( Garcinia mangostana L.), an extraction method for industrial application was explored. A high yield of α-mangostin (5.2%) was obtained by extraction from dried mangosteen pericarps with subsequent purification on macroporous resin HPD-400. The chemical structure of α-mangostin was verified mass spectrometry (MS), nuclear magnetic resonance ( 1 H NMR and 13 C NMR), infrared spectroscopy (IR) and UV-Vis spectroscopy. The purity of the obtained α-mangostin was 95.6% as determined by HPLC analysis. The binding of native α-mangostin to human serum albumin (HSA) or transferrin (TRF) was explored by combining spectral experiments with molecular modeling. The results showed that α-mangostin binds to HSA or TRF as static complexes but the binding affinities were different in different systems. The binding constants and thermodynamic parameters were measured by fluorescence spectroscopy and absorbance spectra. The association constant of HSA or TRF binding to α-mangostin is 6.4832×10 5 L/mol and 1.4652×10 5 L/mol at 298 K and 7.8619×10 5 L/mol and 1.1582×10 5 L/mol at 310 K, respectively. The binding distance, the energy transfer efficiency between α-mangostin and HSA or TRF were also obtained by virtue of the Förster theory of non-radiation energy transfer. The effect of α-mangostin on the HSA or TRF conformation was analyzed by synchronous spectrometry and fluorescence polarization studies. Molecular docking results reveal that the main interaction between α-mangostin and HSA is hydrophobic interactions, while the main interaction between α-mangostin and TRF is hydrogen bonding and Van der Waals forces. These results are consistent with spectral results.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2017
·
IF 4.162
Yingzi Wang,Yaping Ding,Li Li,Ping Hu
In present study, a novel and facile electrochemical sensor based on glassy carbon electrode (GCE) modified with nitrogen-doped carbon nanotubes (N-CNT) decorated with poly (L-Cysteine) (PLCY) were fabricated and applied for the simultaneous voltammetric determination of theophylline (THEO) and caffeine (CAF). The morphology and structure of multilayer film modified on the surface of glassy carbon electrode were investigated successfully by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and Raman Spectroscopy. And the properties of the modified electrode were investigated by Chronocoulometry (CC), Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) were utilized to investigate the electrochemical behavior of THEO and CAF on the composite film modified electrode. The results showed that the determination towards THEO and CAF can be operated at the same potential window with the oxidation current peak separated and non-interfering respectively. Compared to the bare GCE, the PLCY/N-CNT/GCE can signally meliorate the electrocatalytic activity towards the oxidation of THEO and CAF with a remarkably increase in the anodic peak currents of 495.94% and 465.48%. Under the optimal conditions, the fabrication multilayer film sensor had excellent performances in determination towards THEO and CAF with a wide linear dynamic range from 0.10 to 70.0 μM and 0.40–140.0 μM, low detection limit (S/N = 3) of 0.033 μM and 0.20 μM, respectively. The PLCY/N-CNT/GCE sensor also had advantages as easy-made, high-sensitivity, stability and reproducibility. Moreover, it was successfully used to analyze the THEO and CAF in green tee, oral theophylline sustained release tablets and energy drink sample with a satisfactory result.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2013
·
IF 3.554
Yu Ouyang,Xiang Cai,QingShan Shi,Lili Liu,Dongliang Wan,Shaozao Tan,Yousheng Ouyang
In order to improve the water-solubility and long-term antibacterial activity of copper nanoparticles (CuNPs), a poly- l -lysine-modified reduced graphene oxide (PLL–rGO) was used as the carrier of CuNPs, and a poly- l -lysine/reduced graphene oxide/copper nanoparticles (PLL–rGO–CuNPs) hybrid was prepared by anchoring the CuNPs on the reduced graphene oxide surface. The novel PLL–rGO–CuNPs hybrid was characterized and the antibacterial activity of it on gram-negative Escherichia coli and Gram-positive Staphylococcus aureus was tested. Such a hybrid showed additively antibacterial activity, and the CuNPs on PLL–rGO were more stable than those on polyvinyl pyrrolidone, resulting in long-term additively antibacterial effect. Meanwhile, this hybrid showed excellent water-solubility, suggesting great potential application in microbial control.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2012
·
IF 2.905
Yamin Li,Zhuo Ye,Jing Zhou,Jie Liu,Ge Song,Kai Zhang,Baoxian Ye
A novel voltammetric sensor based on graphene–Nafion and poly( L -arginine) was constructed by electrodeposited and simple dipping–drying methods and used for high-sensitive determination of Terbutaline sulfate (TBS). The resulting poly( L -arginine)/graphene–Nafion modified electrode showed a significant voltammetric response to TBS due to the synergistic effect of poly( L -arginine) and graphene–Nafion, in which poly( L -arginine) had electrocatalytic ability for TBS and graphene provided a large specific surface area, excellent electric conductivity and electrocatalytic activity. The sensor gave a good linear range over 4.0 × 10 −8 –5.0 × 10 −6 mol L −1 with a detection limit of 1.2 × 10 −8 mol L −1 towards the determination of TBS. The high sensitivity and selectivity together with the good linear relationship, very easy surface regeneration and good stability at such a modified electrode led us to construct a practical TBS biosensor successfully. This work promoted the potential applications of graphene-based materials in electrochemical sensors.
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2015
·
IF 4.097
Fanyong Yan,Dechao Shi,Tancheng Zheng,Kaiyi Yun,Xuguang Zhou,Li Chen
An “Off–On” approach for highly sensitive and selective detection of mercury ions (Hg 2+ ) and l -cysteine ( l -Cys) was demonstrated with the use of water-soluble carbon dots (CDs) as novel fluorescent probe. In this present sensing system, Hg 2+ cations can efficiently coordinate onto the surface of CDs by means of electrostatic interactions and remarkably quench the fluorescence signal of CDs as a result of the fluorescence charge transfer (turn-off). In addition, the resulting CDs-Hg 2+ system was observed to be sensitive to l -Cys due to the ability of l -Cys to coordinate with Hg 2+ and the formation of strong Hg 2+ -SR bond. When l -Cys was added, Hg 2+ combined with l -Cys rather than with CDs resulting in the remove of Hg 2+ from the surface of CDs and shielding of fluorescence quenching, and thus, a significant fluorescence restore of CDs was observed (turn-on). Under the optimized conditions, good linearity for detecting Hg 2+ was attained over the concentration range from 2 to 22 μM with a detection limit of 0.017 μM, while the concentrations of l -Cys ranging from 2 to 20 μM exhibited a linear relationship with the relative fluorescence intensity with a correlation coefficient of R 2 = 0.99329. Moreover, this CDs-based sensor was successfully applied for visual identification and quantitation of Hg 2+ and l -Cys in real water sample and fluorescence imaging of NIH-3T3 cells with satisfying resolution.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2014
·Vol. 16
·期 4
·1-16
·
IF 2.278
Lian He,Zhang Tianhong,Sun Jin,Pu Xiaohui,Tang Yilin,Zhang Youxi,He Zhonggui
The aim of this study was to evaluate the underlying mechanism of enhanced oral absorption of paclitaxel (PTX)-loaded chitosan–vitamin E succinate– N -acetyl- l -cysteine (CS–VES–NAC) nanomicelles from the cellular level. In aqueous solution, CS–VES–NAC copolymer self-assembled into the polymeric nanomicelles, with the size ranging from 190 to 240 nm and the drug loading content as high as 20.5 %. Cytotoxicity results showed that the PTX-loaded nanomicelles exhibited the similar effect to PTX solution (PTX-Sol) on Caco-2 cells, but no toxicity observed for blank CS–VES–NAC nanomicelles. The cellular uptake of PTX was significantly increased by CS–VES–NAC nanomicelles, compared with that of PTX-Sol, due to the possible escapement of P-glycoprotein (P-gp) efflux pumps by endocytosis pathway. Confocal laser scanning microscope (CLSM) images also confirmed CS–VES–NAC nanomicelles could be effectively internalized by Caco-2 cells. More importantly, P
app value of PTX-loaded CS–VES–NAC nanomicelles was 2.3-fold higher than that of PTX-Sol, and the efflux ratio decreased by more than 10.8-fold for the nanomicelles. As a consequence of opening of tight junctions and P-gp inhibition induced by free CS–VES–NAC copolymer, the P
app value of PTX was almost increased up to 19.5-fold. All the results indicate that CS–VES–NAC copolymer hold great promises as nanocarrier for antitumor drug oral delivery by improving paracellular and transcellular permeation.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）