查找使用阿拉丁产品的科研文献

Core-shell MOFs-based composites of defect-functionalized for mixed-mode chromatographic separation

Tiantian Si,Licheng Wang,Haixia Zhang,Xiaofeng Lu,Xiaojing Liang,Shuai Wang,Yong Guo

The micropores of the metal-organic frameworks (MOFs) endow with the advantages of size selectivity and large specific surface area, etc., but they limit their applications toward the control of diffusion and transport processes. Here, we report a strategy to prepare the hierarchical porous material, functional defect, which allows incorporation of L-Cysteine in the MOF by defect-loading. Silica microspheres were modified with these materials to form core-shell composites and used as mixed-mode stationary phases for chromatographic separations. Compared with the traditional MOFs-based stationary phase, it exhibited superior efficiency and selectivity for separation of various analytes and highlighted the role of defect of MOFs and function of L-Cysteine. In addition to the rapid separation of hydrophobic compounds, the stationary phase showed great potential in the separation of hydrophilic analytes, especially for separation of ten carbohydrates and eight sulfonamides. It showed excellent chromatographic reproducibility and stability, and the repeatability of preparation was investigated by relative standard deviations of retention time and/or column efficiency of objective compounds, which was among different batches less than 1.81%. This demonstration provided deep understanding of separation mechanism between MOF-based composites with functional defect and analytes, and stimulated the wide applications of such defective MOFs complexes in separations and analysis.

Synthesis of Polyaniline/BiPr Composite Oxide Nanowires with Enhanced Electrochemical Sensing Performance

Chenxu Feng,Zhangjie Ban,Jianfeng Huang,Yong Zhang,Zhengyu Cai,Lizhai Pei

BackgroundConsiderable interest has been devoted to electrochemical sensors for the detection of L-cysteine using BiPr-based oxide-modified electrodes due to high specific surface area and good electro-catalytic activity with several oxidation states. The combination of the BiPr composite oxide nanowires with polyaniline (PAn) can promote the electro-catalytic performance towards L-cysteine because PAn can facilitate the electro-catalytic process by enhancing the charge transfer.MethodsPAn/BiPr composite oxide nanowires were obtained via low temperature one-step hydrothermal route. The obtained composite oxide nanowires were analyzed by X-ray diffraction, electron microscopy, and electrochemical methods.ResultsCharacterization results indicate that amorphous PAn nanoparticles with a size of about 50 nm are homogeneously dispersed at the surface of the BiPr composite oxide nanowires. PAn/BiPr composite oxide nanowire-modified electrode shows an enhanced L-cysteine electro-catalytic activity. PAn promotes electro-catalytic activity of the BiPr composite oxide nanowires. A pair of quasi-reversible cyclic voltammetry (CV) peaks exist at +0.49 V, -0.19 V, respectively. PAn/BiPr composite oxide nanowire modified electrode possesses a linear response in L-cysteine concentration of 0.001-2 mM and detection limit of 0.095 μM, good repeatability, and stability.ConclusionPAn/BiPr composite oxide nanowires act as effective electro-catalysts for L-cysteine oxidation resulting in the enhancement of the electro-catalytic activity relative to BiPr composite oxide nanowires.

The EAG response and behavior of the Saperda populnea L. to volatiles from poplar branches

Defu Chi,Xiaocan Li,Jia Yu,Xing Xie,Guangli Wang

In order to investigate the effect of organic volatiles from poplar species on the host plants orientation of Saperda populnea , the essential oil in the 2–3   years old branches from the sapling or mature trees of Populus simonii Carr. and P. simonii Carr.   ×   P. nigra L. were extracted using the steam distillation method. The chemical composition and relative content in essential oil from those branches was analyzed by GC–MS. The main components contained in those volatiles from the four kinds of branches are mainly aromatic compounds such as 1,2 - cyclohexanedione, 2 - cyclohexene - 1 - one, p - xylene and 1,2,3 - trimethylbenzene and so on. The relative content of aromatic compounds contained in branches from saplings was higher than that contained in branches from old tress. EAG response and behavioral reaction of S. populnea L. to those four kinds of distillated essential oil were tested. The results shown that male and female adults of S. populnea L. shown significant choice behavior and strong olfactory response to those essential oil distillated from branches of P. simonii Carr. and P. simonii Carr.   ×   P. nigra L.. The EAG bioassay of S. populnea L. to 10 kinds of monomers compounds which had relative higher contents was tested. The results shown that the EAG response of female adults of S. populnea L. to 1   mol   L −1 p-xylene was intensest and reached 1.027   mV, the strength of their EAG response to 0.1   mol   L −1 phenol took the second place. The EAG response of male adult of S. populnea L. to 1   mol   L −1 p-xylene was strongest and reached to 0.824   mV, the strength of their EAG response to 1   mol   L −1 salicylaldehyde took the second place. In the choice behavior test of S. populnea L. adult to monomeric compound carried out in ‘Y’ type olfactometer have found that female and male adult of S. populnea L. all appeared obvious positive taxis to 0.1   mol   L −1 p-xylene. The selection rate of female and male adults ware (76.7   ±   4.1)% and (71.7   ±   2.6)%, respectively. The selective reaction to 0.1   mol   L −1 1,2-cyclohexanedione and 2-cyclohexene-1-one were not obviously than that to 0.1   mol   L −1 p-xylene. The male and female adult of S. populnea L. appeared repelling behavior to 0.1   mol   L −1 salicylaldehyde.

Medicinal Effect, In Silico Bioactivity Prediction, and Pharmaceutical Formulation of Ageratum conyzoides L.: A Review

Jasvidianto C. Kotta,Agatha B. S. Lestari,Damiana S. Candrasari,Maywan Hariono

Goat weed (Ageratum conyzoides L.), or bandotan in Indonesia, is an herbaceous plant that broadly grows up in both subtropical as well as tropical areas. This herb contains many phytoconstituents which have many benefits in different aspects. The essential oil contains phytochemicals such as phenol, phenolic ester, and coumarin, whereas many compounds can been identified in the whole part such as terpenoid, steroid, chromene, pyrrolizidine alkaloid, and flavonoid. Empirically, this herb has been used as an antihemorrhagic, antiseptic, antileprosy, and wound-healing agent. This article reviews the potency of the herb in medication according to the chemical substances being deposited, which are collected from numerous studies, followed by its in silico bioactivity prediction as well as its pharmaceutical dosage form formulation.

Antibacterial and anti-adhesion effects of the silver nanoparticles-loaded poly(l-lactide) fibrous membrane

Shen Liu,Jingwen Zhao,Hongjiang Ruan,Wei Wang,Tianyi Wu,Wenguo Cui,Cunyi Fan

The complications of tendon injury are frequently compromised by peritendinous adhesions and tendon sheath infection. Physical barriers for anti-adhesion may increase the incidence of postoperative infection. This study was designed to evaluate the potential of silver nanoparticles (AgNPs)-loaded poly( l -lactide) (PLLA) electrospun fibrous membranes to prevent adhesion formation and infection. Results of an in vitro drug release study showed that a burst release was followed by sustained release from electrospun fibrous membranes with a high initial silver content. Fewer fibroblasts adhered to and proliferated on the AgNP-loaded PLLA electrospun fibrous membranes compared with pure PLLA electrospun fibrous membrane. In the antibacterial test, the AgNP-loaded PLLA electrospun fibrous membranes can prevent the adhesion of Gram-positive Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa . Taken together, these results demonstrate that AgNP-loaded PLLA electrospun fibrous membranes have the convenient practical medical potential of reduction of infection and adhesion formation after tendon injury.

3D Printed Zn-doped Mesoporous Silica-incorporated Poly-L-lactic Acid Scaffolds for Bone Repair

Guowen Qian,Lemin Zhang,Guoyong Wang,Zhengyu Zhao,Shuping Peng,Cijun Shuai

Poly-L-lactic acid (PLLA) lacks osteogenic activity, which limits its application in bone repair. Zinc (Zn) is widely applied to strengthen the biological properties of polymers due to its excellent osteogenic activity. In the present study, Zn-doped mesoporous silica (Zn-MS) particles were synthesized by one-pot hydrothermal method. Then, the particles were induced into PLLA scaffolds prepared by selective laser sintering technique, aiming to improve their osteogenic activity. Our results showed that the synthesized particles possessed rosette-like morphology and uniform mesoporous structure, and the composite scaffold displayed the sustained release of Zn ion in a low concentration range, which was attributed to the shield effect of the PLLA matrix and the strong bonding interaction of Si-O-Zn. The scaffold could evidently promote osteogenesis differentiation of mouse bone marrow mesenchymal stem cells by upregulating their osteogenesis-related gene expression. Besides, Zn-MS particles could significantly increase the compressive strength of the PLLA scaffold because of their rosette-like morphology and mesoporous structure, which can form micromechanical interlocking with the PLLA matrix. The Zn-MS particles possess great potential to improve various polymer scaffold properties due to their advantageous morphology and physicochemical properties.

Effects of chitosan nanoparticles on seed germination and seedling growth of wheat (Triticum aestivum L.)

Ruixin Li,Jinxia He,Hongguo Xie,Wenxia Wang,Santosh Kumar Bose,Yeqing Sun,Jianen Hu,Heng Yin

To investigate the effect and mechanism of chitosan nanoparticles (CSNPs) on the germination and seedling growth of wheat ( Triticum aestivum L.), we conducted systematic research on the impact of different concentrations (1–100 μg/mL) of CSNPs and chitosan (CS). The result of energy-dispersive spectroscopy (EDS) and confocal laser scanning microscopy (CLSM) showed that adsorption of CSNPs on the surface of wheat seeds was higher than that of CS. CSNPs had growth promoting effect at a lower concentration (5 μg/mL) compared with CS (50 μg/mL). In addition, the application of 5 μg/mL CSNPs induced the auxin-related gene expression, accelerated indole-3-acetic acid (IAA) biosynthesis and transport, and reduced IAA oxidase activity resulting in the increase of IAA concentration in wheat shoots and roots. The results suggest that CSNPs have positive effect on seed germination and seedling growth of wheat at a lower concentration than CS due to higher adsorption on the surface of wheat seeds.

DNA damage protection and 5-lipoxygenase inhibiting activity of areca (Areca catechu L.) inflorescence extracts

W Chen,C Zhang,Y Huang,F Cheng,S Zhao,Y Shen,J Liu

RNA-Seq and genetic diversity analysis of faba bean (Vicia faba L.) varieties in China

Wanwei Hou,Xiaojuan Zhang,Yuling Liu,Yujiao Liu,Bai li Feng

Background Faba bean ( Vicia faba L) is one of the most important legumes in the world. However, there is relatively little genomic information available for this species owing to its large genome. The lack of data impedes the discovery of molecular markers and subsequent genetic research in faba bean. The objective of this study was to analyze the faba bean transcriptome, and to develop simple sequence repeat (SSR) markers to determine the genetic diversity of 226 faba bean varieties derived from different regions in China. Methods Faba bean varieties with different phenotype were used in transcriptome analysis. The functions of the unigenes were analyzed using various database. SSR markers were developed and the polymorphic markers were selected to conduct genetic diversity analysis. Results A total of 92.43 Gb of sequencing data was obtained in this study, and 133,487 unigene sequences with a total length of 178,152,541 bp were assembled. A total of 5,200 SSR markers were developed on the basis of RNA-Seq analysis. Then, 200 SSR markers were used to evaluate polymorphisms. In total, 103 (51.5%) SSR markers showed significant and repeatable bands between different faba bean varieties. Clustering analysis revealed that 226 faba bean materials were divided into five groups. Genetic diversity analysis revealed that the relationship between different faba beans in China was related, especially in the same region. These results provided a valuable data resource for annotating genes to different categories and developing SSR markers.

Components identification and isomers differentiation in pigeon pea (Cajanus cajan L.) leaves by LC-MS

Zili Guo,Peixi Zhu,Xiaoai He,Tianhe Yan,Xianrui Liang

A valid and reliable method based on ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry using electrospray ionization was established to identify chemical constituents in the ethanol extract of pigeon pea leaves. A total of 58 compounds were detected both in positive and negative modes. Among them, 42 compounds, including 16 flavones, 1 flavonol, 5 flavanones, 9 isoflavones, 1 coumarin, 1 lactone, 6 stilbenes, 2 chalcones, and 1 other compound, were unambiguously identified or tentatively assigned in view of the retention time, the molecular formula, as well as the fragmentation patterns. Moreover, eight sets of isomers were differentiated by the ion trap mass spectrometry based on the fragment ion differences or the abundance differences of the same fragment ions. The energy-resolved mass spectrometry in light of the relative abundance of characteristic fragment ions was adopted in the study.

Mechanistic studies of perfluorooctane sulfonate, perfluorooctanoic acid uptake by maize (Zea mays L. cv. TY2)

Wen Bei,Li Longfei,Liu Yu,Zhang Hongna,Hu Xiaoyu,Shan Xiao-quan,Zhang Shuzhen

Background and aims Perfluorinated compounds (PFCs) are of particular environmental concern. The migration of PFCs from soil to plants is a likely pathway for PFCs to enter the human food chain. This study aimed to investigate the uptake mechanisms of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) by maize ( Zea mays L. cv. TY2). Methods Hydroponic greenhouse experiments were performed. Results The kinetics of PFOS and PFOA uptake fitted Mechaelis-Menten equation well, suggesting their carrier-mediated influx processes. Uptake of PFOS was insensitive to metabolic inhibitors (NaN 3 and Na 3 VO 4 ). In contrast, treated with NaN 3 and Na 3 VO 4 reduced the uptake of PFOA by 83 and 43 % respectively. PFOS uptake was decreased by 31 % and 25 % when plants were treated with aquaporin inhibitors, AgNO 3 and glycerol, respectively, while aquaporin inhibitors had no effect on PFOA uptake. Anion channel blockers, 4, 4′-diisothiocyanostibene-2,2′-disolfonate (DID) and 5-nitro 2-(3-phenylpropylamine) benzoic acid (NPPB) inhibited the uptake of PFOS by 33 % and 30 %, respectively. Anion channel blocker anthracene-9-carboxylic acid (9-AC) decreased the uptake of PFOA by 28 %. No competitive uptake was found between PFOS and PFOA. Conclusions Uptake of PFOS and PFOA by maize may have different mechanisms.

Photosynthesis and related metabolic mechanism of promoted rice (Oryza sativa L.) growth by TiO2 nanoparticles

Zhang Yingdan,Liu Na,Wang Wei,Sun Jianteng,Zhu Lizhong

Titanium dioxide nanoparticle (nano-TiO 2 ), as an excellent UV absorbent and photo-catalyst, has been widely applied in modern industry, thus inevitably discharged into environment. We proposed that nano-TiO 2 in soil can promote crop yield through photosynthetic and metabolic disturbance, therefore, we investigated the effects of nano-TiO 2 exposure on related physiologic-biochemical properties of rice ( Oryza sativa L.). Results showed that rice biomass was increased >30% at every applied dosage (0.1–100 mg/L) of nano-TiO 2 . The actual photosynthetic rate (Y(II)) significantly increased by 10.0% and 17.2% in the treatments of 10 and 100 mg/L respectively, indicating an increased energy production from photosynthesis. Besides, non-photochemical quenching (Y(NPQ)) significantly decreased by 19.8%–26.0% of the control in all treatments respectively, representing a decline in heat dissipation. Detailed metabolism fingerprinting further revealed that a fortified transformation of monosaccharides (D-fructose, D-galactose, and D-talose) to disaccharides (D-cellobiose, and D-lactose) was accompanied with a weakened citric acid cycle, confirming the decrease of energy consumption in metabolism. All these results elucidated that nano-TiO 2 promoted rice growth through the upregulation of energy storage in photosynthesis and the downregulation of energy consumption in metabolism. This study provides a mechanistic understanding of the stress-response hormesis of rice after exposure to nano-TiO 2 , and provides worthy information on the potential application and risk of nanomaterials in agricultural production.