ADVANCED POWDER TECHNOLOGY
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2021
·
IF 4.833
Xinyue Chen,Dan Liu,Sanhu Gou,Jiahui Ji,Zhiyuan Xue,Shilan Feng
A colorimetric assay based on the oriented TA-AuNPs-PEG-FITC for rapid and sensitive PABA detection was proposed. Initially, the negatively charged TA modified on the surface of AuNPs enabled rapid binding to PABA due to the electrostatic interaction and hydrogen bond, resulting in a visible color change. However, particles were aggregated in a non-oriented way, leading to an unstable testing system which failed to realize the accurate quantification. Thus, the asymmetrically functionalized TA-AuNPs-PEG-FITC were prepared, in which the stabilizer agent of HS-PEG-FITC was attached to the specific sites on the surface of TA-AuNPs. Such a way of modification resulted in an oriented aggregation manner, the addition of PABA induced the formation of oligomers. Moreover, the introduction of FITC group acted as fluorescent marker, providing a simple, fast and quantitative method for characterization of PEG chain. The molar ratio between TA-AuNPs and modified PEG-FITC was further determined. A linear regression was established in a wide range from 10 μM to 1 mM with the LOD of 6.9 μM. Finally, the sensor was successfully applied in the health food. This was the first example in which TA-AuNPs-PEG-FITC were fabricated for colorimetric detection of PABA, and an indirect method based on fluorescence marker was well used to quantify the content of PEG chain.
研究领域:
分析化学
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纳米生物学
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食品科学
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DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2022
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IF 4.119
Shengzhe Jia,Ye Gao,Zongqiu Li,Teng Zhang,Jian Liu,Jingkang Wang,Zhenguo Gao,Junbo Gong
This study explores the process intensification techniques and process control strategies on the product properties optimization. α-PABA, a long needle-like shape, can cause problems for the downstream processing. This study proposes ultrasound technique, supercooling control (SSC), and temperature cycling (TC) technologies to optimize the morphology and crystal size distribution of α-PABA. Firstly, the solubility and metastable zone of α-PABA in ethanol solvent are measured to determine the operational range. Next, the concentration calibration model is established to correlate the solubility with the ATR-FTIR intensity and temperature qualitatively. Furthermore, the process improvement techniques and control strategies are introduced to optimize the products. The ultrasound intensification contributes to produce the uniform crystal seeds. The SSC is benefit for the crystal growth, and can reduce the L/D ratio of the crystal product. While, TC is an efficient tool to eliminate the fine crystals. Moreover, the combination of ultrasound, SSC, and TC technology can show a significant improvement on the product particle aspects. The L/D ratio, crystal size, crystal morphology can show different degree of improvement under the combination techniques. At last, the outlook and perspectives on the process analytical technology are developed.
研究领域:
化学工程
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过程控制
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DOI
高影响因子
Nanoscale Advances
·
2018
·Vol. 1
·期 3
·1207-1214
·
IF 0
Mohammed Hassan Ibrahim,Zhonghua Xue,Hassan Idris Abdu,Mahgoub Ibrahim Shinger,Ahmed Mahmoud Idris,Murtada Mohamed Edris,Duoliang Shan,Xiaoquan Lu
Nitrite ions (NO2−), as one of the important inorganic anions, exhibit considerable effects towards the environment and human health. Moreover, over intake of this anion may cause dangerous diseases. Herein, we successfully fabricated silver nanoparticles (AgNPs) using 4-amino-5-hydroxynaphthalene-2, 7-disulphonic acid monosodium salt (AHNDMS) and functionalized them with p-aminobenzoic acid (PABA), and used the functionalised AgNPs as a sensitive and selective colorimetric sensor for nitrite ions. The structure of the as-prepared pure AgNPs was experimentally characterized by different characterizations methods, namely, UV-vis, FT-IR, CV, DPVs, SEM, TEM, and XRD. Additionally, the nitrite ion sensitively and selectively changes the brownish yellow color of the dispersed AgNPs to pinkish red, indicating aggregation of AgNPs, with a detection limit of 0.016 ppm (0.348 μM) and 0.0069 ppm (0.149 μM) by the naked-eye and by UV-vis spectroscopy, respectively. The color change suggested that the aggregation of AgNPs was induced by nitrite-selective diazo-coupling. UV-vis spectra show the disappearance of the absorbance at 474 nm and appearance of a new peak at 532 nm, presumably due to the conversion of AgNPs to silver ions. Moreover, the studies of interference in the proposed sensor confirm its selectivity in the presence of anions as well as cations. Furthermore, linearity was observed between the absorption and the concentration of nitrite ions. More importantly, the proposed sensor was practicably applied for the determination of nitrite in different water samples, such as distilled water, river water, and tap water.
研究领域:
环境科学
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分析化学
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DOI
PubMed
ANALYTICA CHIMICA ACTA
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2024
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IF 5.7
Yingying Zhong,Qing Wang,Zi-Jian Chen,Hongwu Wang,Suqing Zhao
Background In vitro screening strategies based on the inhibition of α-glucosidase (GAA) activity have been widely used for the discovery of potential antidiabetic drugs, but they still face some challenges, such as poor enzyme stability, non-reusability and narrow range of applicability. To overcome these limitations, an in vitro screening method based on GAA@GOx@Cu-MOF reactor was developed in our previous study. However, the method was still not satisfactory enough in terms of construction cost, pH stability, organic solvent resistance and reusability. Thence, there is still a great need for the development of in vitro screening methods with lower cost and wider applicability. Results A colorimetric sensing strategy based on GAA/(Au–Au/IrO 2 )@Cu(PABA) cascade catalytic reactor, which constructed through simultaneous encapsulating Au–Au/IrO 2 nanozyme with glucose oxidase-mimicking and peroxidase-mimicking activities and GAA in Cu(PABA) carrier with peroxidase-mimicking activity, was innovatively developed for in vitro screening of GAA inhibitors in this work. It was found that the reactor not only exhibited excellent thermal stability, pH stability, organic solvent resistance, room temperature storage stability, and reusability, but also possessed cascade catalytic performance, with approximately 12.36-fold increased catalytic activity compared to the free system (GAA + Au–Au/IrO 2 ). Moreover, the in vitro GAA inhibitors screening method based on this reactor demonstrated considerable anti-interference performance and detection sensitivity, with a detection limit of 4.79 nM for acarbose. Meanwhile, the method owned good reliability and accuracy, and has been successfully applied to the in vitro screening of oleanolic acid derivatives as potential GAA inhibitors. Significance This method not only more effectively solved the shortcomings of poor stability, narrow scope of application, and non-reusability of natural enzymes in the classical method compared with our previous work, but also broaden the application scope of Au–Au/IrO 2 nanozyme with glucose oxidase and peroxidase mimicking activities, and Cu(PABA) carrier with peroxidase mimicking activity, which was expected to be a new generation candidate method for GAA inhibitor screening.
研究领域:
生物技术
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催化
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药物发现
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酶学
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分析化学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Yingying Zhong,Tiantian Wang,Zhiting Lao,Minglei Lu,Shan Liang,Xiping Cui,Qing-lan Li,Suqing Zhao
Herein, a Au-Au/IrO2 nanocomposite with tandem enzyme-mimicking activity was innovatively synthesized, which can show outstanding glucose oxidase (GOx)-like activity and peroxidase-like activity simultaneously under neutral conditions. Moreover, a Au-Au/IrO2@Cu(PABA) reactor was prepared via encapsulation of the Au-Au/IrO2 nanocomposite in a Cu(PABA) metal organic framework. The reactor not only exhibits excellent organic solvent stability, acid resistance, and reusability but also displays better cascade reaction catalytic efficiency (kcat/Km = 148.86 min–1 mM–1) than the natural free enzyme system (GOx/HRP) (kcat/Km = 98.20 min–1 mM–1) and Au-Au/IrO2 nanocomposite (kcat/Km = 135.24 min–1 mM–1). In addition, it is found that the reactor can catalyze glucose or dissolved oxygen to produce active oxygen species (ROS) including HO, 1O2, and O2–· through its enzyme-mimicking activity. Finally, the novel reactor was successfully used in organic dye degradation and antibacterial application. The results show that it can effectively degrade methyl orange, methylene blue, and rhodamine B, which all can reach a degradation rate of nearly 100% after interacting with Au-Au/IrO2@Cu (PABA) for 3.5 h. Furthermore, the reactor also exhibits excellent antibacterial activity, so as to achieve a complete bactericidal effect to Staphylococcus aureus and Escherichia coli at a concentration of 12.5 μg mL–1.
研究领域:
纳米材料
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催化
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环境科学
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材料科学
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生物技术
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
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2024
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IF 3.7
Hongbo Suo,Xinzheng Liu,Shu Chen,Qi Li,Xiangnan Liu,Lili Xu
Biodiesel is more environmentally friendly compared to traditional petroleum diesel. The method of producing biodiesel catalyzed by lipases, as a green chemistry technology, can further reduce its negative impact on the environment. In this work, lipase immobilized on magnetic cellulose was embedded in Cu(PABA), and then the biocomposite (MCL@Cu(PABA)) was used for biodiesel production. The good biocompatibility and flexible skeleton structure of cellulose can buffer the compression effect on enzyme molecules during the formation of Metal-Organic Frameworks (MOFs), and the MOFs protective layer can reduce the damage caused by denaturants to enzyme molecules. The biocatalyst showed enhanced activity and stability with a lower deactivation constant ( K d ). Under the optimized reaction conditions, the biodiesel yield can reach 78.4 %. After reused for 7 times, the biocatalyst can still achieve a biodiesel yield of 58.8 %. Moreover, after stored for 30 days, the biodiesel yield can still reach 70.3 %. For all experimental yields, the standard deviation (SD) ranged from 2.4 % to 4.5 %. Secondary structure analysis showed that the rigid structure and active conformation of lipase was enhanced after Cu(PABA) encapsulation.
研究领域:
生物化学
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环境科学
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DOI
高影响因子
Applied Sciences-Basel
·
2019
·Vol. 9
·期 14
·2873
·
IF 2.217
Ruirui Han,Qiang Wu,Chihao Lin,Lingfeng Zhang,Zhicai Zhai,Ping Sun,Yingsen Fang,Jiaqiang Wu,Hui Liu
Featured ApplicationThis work provides basic data, application references and theoretical guidance of the UV/PDS process for the removal of PABA-type UV filters in water.AbstractIn this paper, the ultraviolet/persulfate (UV/PDS) combined oxidation process was used to remove the ethyl 4-aminobenzoate (Et-PABA), one of the typical 4-aminobenzoic acid (PABA)-type UV filters. The effects of various factors on the removal of Et-PABA using the UV/PDS process were investigated, and the degradation mechanisms of Et-PABA were explored. The results showed that the UV/PDS process can effectively remove 98.7% of Et-PABA within 30 min under the conditions: UV intensity of 0.92 mW·cm−2, an initial concentration of Et-PABA of 0.05 mM, and a PDS concentration of 2 mM. The removal rate of Et-PABA increased with the increase in PDS dosage within the experimental range, whereas humic acid (HA) had an inhibitory effect on Et-PABA removal. Six intermediates were identified based on HPLC–MS and degradation pathways were then proposed. It can be foreseen that the UV/PDS oxidation process has broad application prospects in water treatment.Keywords:advanced oxidation processes (AOPs);UV-activated;persulfate;ethyl 4-aminobenzoate (Et-PABA)
研究领域:
环境科学
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化学工程
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DOI
高影响因子
CHEMPHYSCHEM
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2024
·Vol. 25
·期 14
·e202400151
·
IF 2.3
Chang Yang Wang,Long Zhao,Ralf I. Kaiser
Polycyclic aromatic hydrocarbons (PAHs) imply the missing link between resonantly stabilized free radicals and carbonaceous nanoparticles, commonly referred to as soot particles in combustion systems and interstellar grains in deep space. Whereas gas phase formation pathways to the simplest PAH – naphthalene (C 10 H 8 ) – are beginning to emerge, reaction pathways leading to the synthesis of the 14π Hückel aromatic PAHs anthracene and phenanthrene (C 14 H 10 ) are still incomplete. Here, by utilizing a chemical microreactor in conjunction with vacuum ultraviolet (VUV) photoionization (PI) of the products followed by detection of the ions in a reflectron time-of-flight mass spectrometer (ReTOF-MS), the reaction between the 1′- and 2′-methylnaphthyl radicals (C 11 H 9 ⋅) with the propargyl radical (C 3 H 3 ⋅) accesses anthracene (C 14 H 10 ) and phenanthrene (C 14 H 10 ) via the Propargyl Addition–BenzAnnulation (PABA) mechanism in conjunction with a hydrogen assisted isomerization. The preferential formation of the thermodynamically less stable anthracene isomer compared to phenanthrene suggests a kinetic, rather than a thermodynamics control of the reaction. Graphical The reaction between the 1’- and 2’-methylnaphthyl radicals (C 11 H 9 ⋅) with the propargyl radical (C 3 H 3 ⋅) accesses anthracene (C 14 H 10 ) and phenanthrene (C 14 H 10 ) via the Propargyl Addition–BenzAnnulation (PABA) mechanism in conjunction with a hydrogen assisted isomerization.
研究领域:
物理化学
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燃烧化学
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天体化学
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有机反应机理
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质谱学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
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IF 12.5
Kai Wang,Chunqing Niu,Xin Zhang,Nuo Liu,Zhengxin Luo,Chunhong Zhu,Jian Shi
A mixed mono−/multidentate ligand strategy engineered defective MIL-100(Fe). • Coordinatively unsaturated Fe O sites promoted rapid heavy-metal adsorption. • Defect engineering integrated Fe O exposure and amino functionalization. • Synergistic Fe–O/NH₂/COO − sites enhanced adsorption kinetics and affinity. • A flexible MOF membrane achieved efficient and recyclable heavy-metal removal. To address Pb(II) and Cd(II)-dominated heavy-metal contamination in water, a series of amino-bearing, defect-regulated Fe-based metal-organic frameworks (MOFs) were constructed using ligand engineering. In the synthetic design, the tritopic linker 1,3,5-benzenetricarboxylic acid (H₃BTC) was coupled with the monotopic modulator p-aminobenzoic acid (PABA), enabling the simultaneous generation of coordinatively unsaturated Fe O centers and exposed -NH₂ functionalities within the framework. This dual functionalization substantially strengthened the affinity of the adsorbent for divalent heavy-metal ions. Among the obtained samples, 6 mg Fe(BTC)₈(PABA)₂, corresponding to an H₃BTC/PABA feed ratio of 8:2, delivered the best adsorption performance under the conditions of 25 °C, pH 5, and an initial concentration of 150 mg/L, with maximum uptake values of 732.03 mg/g for Pb(II) and 654.05 mg/g for Cd(II), and equilibrium was achieved within 15 min. Kinetic and equilibrium analyses followed the pseudo-second-order model and Langmuir isotherm, respectively, indicating that monolayer chemisorption dominates the capture process. To improve the handling, recovery, and reusability of Fe(BTC)₈(PABA)₂ particles, they were incorporated into a polyacrylonitrile (PAN) nanofibrous matrix via electrospinning to obtain a Fe(BTC)₈(PABA)₂@PAN membrane. The membrane retained good structural stability and pronounced selectivity, particularly for Pb(II), in both binary-ion media and multi-cationic aqueous systems. After five adsorption-desorption cycles, more than 83% of the initial adsorption capacity was retained. DFT (Density functional theory) calculations further supported the experimental observations, showing that the adsorption originated from cooperative coordination among unsaturated Fe-O-M sites, carboxyl oxygen atoms, and amino nitrogen atoms. Therefore this study provides a defect- and functionality-coupled strategy for developing MOF-based adsorbents with both rapid uptake and high capacity for heavy-metal remediation. Download: Download high-res image (331KB) Download: Download full-size image
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高影响因子
International Journal of Environmental Research and Public Health
·
2020
·Vol. 17
·期 2
·651
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IF 2.849
Xinxin Huang,Yuanyuan Li,Tantan Wang,Hui Liu,Jiaqi Shi,Xuesheng Zhang
Organic UV filters are a kind of emerging pollutants, which have been widely used in personal care products (PCPs). This study evaluated the effects of benzophenone-4 (BP-4), 4-aminobenzoic acid (PABA), and 2-phenylbenzimidazole-5-sulfonic acid (PBSA) on the selected indices of antioxidative responses in zebrafish (Danio rerio) liver. Zebrafish were exposed to two different doses (i.e., 0.5 and 5 mg L−1) of semi-static water with three individual compounds. Liver samples were collected on 7 and 14 days to analyze biochemical indicators, including superoxide dismutase (SOD), glutathione S-transferase (GST), reduced glutathione (GSH), and malondialdehyde (MDA). Oxidative stress occurred in zebrafish liver with significantly changed indicators during the whole exposure period. Different experimental groups could induce or inhibit the activity of antioxidant enzymes with varying degrees. With a prolonged exposure time and increased exposure dose, the hepatic lipid peroxidation was also obviously observed. Moreover, the toxicity order of three organic UV filters was analyzed using the integrated biomarker response (IBR) index and the results indicate that exposure to PABA for 7 days at 0.5 mg L−1and PBSA for 7 days at 5 mg L−1induced the most severe oxidative stress in the liver of zebrafish.Keywords:organic UV filters;oxidative stress;lipid peroxidation;integrated biomarker response;zebrafish
研究领域:
环境科学
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毒理学
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DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2020
·
IF 3.333
Xingquan Xiong,Hui Zhang,Shi Lin Lai,Jinbin Gao,Lizhu Gao
Lignin is a biodegradable, abundant and renewable natural polymer on earth. In this study, deep eutectic solvents (DESs)-modified lignin heterogeneous catalysts were prepared for the first time via a facile acid-base interaction between choline chloride (ChCl) and p -aminobenzoic acid (PABA) or its derivatives, which were used to efficiently catalyze the cycloaddition of CO 2 and terminal epoxides under green and mild conditions. Among them, lignin-ChCl-PABA was found to exhibit the highest catalytic activity for the cycloaddition of epoxides in the presence of 1.0 MPa of CO 2 while retaining high selectivity, which far outperformed those achieved on the homogeneous EDSs catalytic system. A series of cyclic carbonates could be obtained in high yields (90–99%), and lignin-ChCl-PABA was stable and reusable for the cycloaddition reaction (84% yield after 5 recycles). The attaching DES of ChCl/PABA onto the functional lignin increased the catalytic activity and also made the catalyst easier to recycle from the reaction mixture. The OH and NH 2 groups on the surface of lignin-ChCl-PABA played a very important role in the acceleration of the cycloaddition reaction under solvent free conditions.
研究领域:
化学工程
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材料科学
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环境化学
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绿色化学
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催化
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DOI
高影响因子
Journal of Materials Chemistry B
·
2024
·
IF 6.1
Zhiheng Zhang,Hongchen Chen,Weize Diao,Chuangxin Zhou,Guozhen Liu
Eutectic gallium indium (EGaIn) nanoparticles can be modified with aniline derivatives to introduce versatile functional groups toward bioapplications beyond materials science. The p-aminobenzoic acid (PABA) modified EGaIn (EGaIn-PABA) demonstrated high wettability with the presence of carboxyl groups, but the priority of carboxyl and amino groups binding on EGaIn surface remains unclear. To study the binding nature of PABA to EGaIn, the anti-mouse IgG antibody labeled with fluorescein isothiocyanate (FITC) (IgG-FITC) was covalently modified to EGaIn-PABA to verify the presence of terminal carboxyl groups on EGaIn surface. The binding of gold nanoparticles (AuNPs) to EGaIn-PABA nanoparticles suggested the presence of terminal amino groups on EGaIn surface. Then, taking advantage of the reductive nature of amino groups, the Almar blue fluorescence experiment was designed to determine the co-existence of carboxyl and amino groups on the EGaIn-PABA surface with the approximate ratio of 3:7, suggesting carboxyl groups had a higher probability of binding with the EGaIn surface than that of amino groups. Then, an aptasensor was fabricated on the EGaIn-PABA surface with AuNPs for electrochemical detection of interleukin-6 with a sensitivity of 1 pg/mL.
研究领域:
材料科学
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生物传感器
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纳米技术
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分析化学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）