JOURNAL OF MOLECULAR LIQUIDS
·
2014
·
IF 2.083
Lei Zhang,Zhengjun Cheng,Xiao Guo,Xiaohui Jiang,Rong Liu
We report an investigation of the title process. The corresponding process variables such as the concentration of surfactant, temperature, initial concentration of dye have been optimized by the response surface methodology (RSM). A 2 3 full factorial design was employed to analyze the individual and interaction effects of the process variables. The experimental data have been well-fitted to second order polynomial equations and the models were also examined using the analysis of variance and t test statistics. The obtained optimal conditions are as following: C s = 30.92 μM, T = 20 °C and C OG = 320 mg/L for the orange G , and C s = 34.10 μM, T = 50 °C and C OA = 500 mg/L for the acid orange 7. The measured experimental maximum adsorption capacities for the orange G and acid orange 7 systems under above optimization conditions were 1452.07 and 2352.99 mg/g, which were in good agreement with their corresponding predicted values (1427.13 and 2357.31 mg/g), with small relative errors of 1.72% and − 0.18%, respectively. Moreover, many aspects of the adsorption kinetics and isotherms for the two dyes are presented. The results indicated that the two adsorption equilibriums were achieved within 210 and 240 min for the acid orange 7 and orange G, the pseudo-second-order model was followed, and Langmuir isotherm model could be well described their adsorption data. In addition, the adsorption mechanism of two dyes onto chitosan/surfactant was discussed further by FTIR and X-ray diffraction (XRD) methods.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Huanxuan Li,Jinquan Wan,Yongwen Ma,Yan Wang,Mingzhi Huang
The environmental impact caused by azo dyes such as acid orange 7 (AO7) is currently a major concern, mainly due to their toxicity, potential carcinogenic nature and difficult degradation. This research described the heterogeneous reactions of persulfate with milli-ZVI (1 mm), micro-ZVI (150 μm) and nano-ZVI (50 nm) under various experimental conditions. The results demonstrated that the combination of persulfate with ZVI was efficient in promoting the degradation of AO7 with the pseudo first-order and second-order kinetics reaction, and different ZVI types exhibited respective level of ability to activate persulfate to degrade acid orange 7, which was ranged as nano-ZVI > micro-ZVI > milli-ZVI. However, the presence of dissolved SiO 2 decreased the AO7 degradation ratio and prolonged the persulfate half-life. The iron corrosion products coating on the ZVI after reaction was comprised of α-Fe 2 O 3 , Fe 3 O 4 and α-FeOOH with some Fe 8 O 8 (OH) 6 SO 4 , which was identified by Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR). With the presence of SiO 2 , surface complexes of ≡FeH 3 SiO 4 or ≡ Fe H 2 SiO 4 - for binding of silicates were formed. These observations indicated that the dissolved SiO 2 in the ZVI activated persulfate system affected the corrosion of iron, altered the surface area with the adsorption of SiO 2 , and appeared to influence the decomposition of persulfate and AO7.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2016
·
IF 3.169
Wenzhi Yang,Yibei Zhang,Huiqin Pan,Changliang Yao,Jinjun Hou,Shuai Yao,Luying Cai,Ruihong Feng,Wanying Wu,Dean Guo
Increasing challenge arising from configurational interconversion in aqueous solvent renders it rather difficult to isolate high-purity tautomeric reference standards and thus largely hinders the holistic quality control of traditional Chinese medicine (TCM). Spiro oxindole alkaloids (SOAs), as the markers for the medicinal Uncaria herbs, can easily isomerize in polar or aqueous solvent via a retro-Mannich reaction. In the present study, supercritical fluid chromatography (SFC) is utilized to separate and isolate two pairs of 7-epimeric SOAs, including rhynchophylline ( R ) and isorhynchophylline ( IR ), corynoxine ( C ) and corynoxine B ( CB ), from Uncaria macrophylla . Initially, the solvent that can stabilize SOA epimers was systematically screened, and acetonitrile was used to dissolve and as the modifier in SFC. Then, key parameters of ultra-high performance SFC (ultra-performance convergence chromatography, UPC 2 ), comprising stationary phase, additive in modifier, column temperature, ABPR pressure, and flow rate, were optimized in sequence. Two isocratic UPC 2 methods were developed on the achiral Torus 1-AA and Torus Diol columns, suitable for UV and MS detection, respectively. MCI gel column chromatography fractionated the U. macrophylla extract into two mixtures ( R / IR and C / CB ). Preparative SFC, using a Viridis Prep Silica 2-EP OBD column and acetonitrile-0.2% diethylamine in CO 2 as the mobile phase, was finally employed for compound purification. As a result, the purity of four SOA compounds was all higher than 95%. Different from reversed-phase HPLC, SFC, by use of water-free mobile phase (inert CO 2 and aprotic modifier), provides a solution to rapid analysis and isolation of tautomeric reference standards for quality control of TCM.
研究领域:
中药学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 18
·12837-12849
·
IF 2.993
Han Zongzhuang,Shen Yu,Wang Fumin,Zhang Xubin
Hierarchical titanium silicalite-1 (TS-1) without generated anatase TiO 2 species was synthesized in the presence of polyquaternium-7 (M550) by one-step hydrothermal crystallization method and characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray fluorescence (XRF), Fourier transform infrared spectra, ultraviolet visible spectra, Raman spectroscopy and N 2 adsorption–desorption measurements. The experimental results show that highly porous TS-1 crystals, with pores of ca. 2.6–4.9 nm diameter, are obtained under hydrothermal conditions by using polyquaternium-7 as the mesopore-directing agent. The polyquaternium-7 has a great influence on both the textural properties and the coordination of Ti species in the framework of TS-1. The catalytic properties and recyclability of the prepared mesoporous TS-1 for hydroxylation of phenol with H 2 O 2 have been evaluated, and their activity has been compared with those of TS-1 with only micropores. The great catalytic activity, selectivity and stability of the hierarchical TS-1 as well as the cheap price and environmental-friendly nature of the used mesopore-directing agent allow to consider this hierarchical TS-1 as a promising catalyst for industry application.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Biomaterials Science
·
2024
·Vol. 12
·期 20
·5266-5273
·
IF 5.8
Tao Hu,Ji-Na Hao,Yongsheng Li
Rapid and accurate detection of 7-methylguanine (m7Gua), a biomarker reflecting the degree of DNA methylation that occurs before or in the early stage of cancer, is of particular significance but remains a great challenge. Herein, a luminescent lanthanide-based covalent organic framework (Ln-COF) probe, namely DPA/Eu@ETTA-DHTA, is designed for the first time for the identification of m7Gua by assembling pyridine-2,6-dicarboxylic acid (DPA) as both an energy donor and a recognition molecule and Eu3+ ions as signal reporters into a stable COF matrix with high porosity and available binding sites. Significantly, the characteristic luminescence of Eu3+ ions can be turned on by the grafted DPA in the COF probe and effectively quenched by the addition of m7Gua via a competitive absorption process, thus achieving the sensing of m7Gua. Such a Ln-COF-based fluorescent platform presents high selectivity and a rapid response (<1 min) to m7Gua with a low detection limit (μM level) even in the presence of the main coexisting species in urine, allowing it to serve as a potentially practical probe for point-of-care monitoring of the level of m7Gua in human urine specimens. This study provides a convenient, time-saving, and economical approach for visual detection of m7Gua, and opens up new perspectives for the design of a luminescent COF-based probe for DNA methylation evaluation in diagnostics.
研究领域:
生物化学
·
医学诊断
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULAR PHARMACEUTICS
·
2019
·
IF 4.396
Kai Dong,Qiuya Lei,Hongfei Qi,Yanni Zhang,Ning Cui,Xianglong Wu,Li Xie,Xiaocheng Yan,Tingli Lu
The excessive increase of intracellular reactive oxygen species (ROS) makes tumor cells usually in the state of oxidative stress. Although tumor cells can adapt to this state to a certain extent by upregulating antioxidant systems, the further ROS insults disrupt the transient intracellular redox balance, eventually leading to apoptosis and necrosis. Therefore, increasing the intracellular ROS level can effectively amplify the oxidative stress and induce apoptosis, which can be employed as a strategy for tumor treatment. Herein, a unique pH-responsive ROS inducing micellar system was reported in this study to specifically amplify the ROS signal in tumor cells. This micellar system was constructed by a new amphiphilic polymer, PIAThydCA, composed of poly(itaconic acid) (PIA) as the hydrophilic backbone, d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) as the hydrophobic side chain, and cinnamaldehyde (CA) as the ROS-generating agent, which were linked to PIA by the pH-sensitive hydrazone bond. PIAThydCA micelles could be degraded in the intracellular acidic environment through the hydrolysis of hydrazone bond and release CA. CA and TPGS could amplify oxidative stress cooperatively to kill MCF-7 human breast cells preferentially through the mitochondrial apoptosis pathway. Therefore, we anticipate that the PIAThydCA micelles could exert great potential in anticancer therapy.
研究领域:
药理学
·
肿瘤学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2017
·Vol. 4
·期 5
·1037-1044
·
IF 6.047
Wen-Jing Wang,Jun-Mei Xia,Xin Hai,Ming-Li Chen,Jian-Hua Wang
The nucleophilic substitution reaction between 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) and –NH2 groups on amino-functionalized carbon dots (CDs) produces a novel carbon dot-based hybrid, CDs@NBD for short. In addition to the characteristic fluorescence emission of carbon dots at λex/λem = 360/443 nm, the CDs@NBD hybrid gives rise to new photoluminescence at λex/λem = 460/544 nm, which is significantly quenched by p-phenylenediamine (PPD) via static quenching. This provides a novel sensing approach for fluorometric detection of PPD with CDs@NBD as a probe. A linear calibration graph is obtained within two concentration ranges of 0.1–1.0 μmol L−1 and 1.0–10.0 μmol L−1, along with a detection limit of 56 nmol L−1 and a RSD of <3% (at 1.0 μmol L−1). The common coexisting species in environmental and biological sample matrices cause no obvious interferences on the detection of PPD. The colour change of the CDs@NBD hybrid solution with the variation in PPD concentration also facilitates visual detection of PPD, which further demonstrates promising applications in environmental and biological sample analysis.
研究领域:
分析化学
·
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Yongxing Shang,Jian Xiong,Shuo Chen,Junjie Zhu,Xiaodie Zhao,Bitao Xiong,Xing’ao Li
Acid Orange 7 (AO7) is a recalcitrant contaminant exhibiting persistent resistance to degradation in aquatic environments. Materials based on graphitic carbon nitride (
) demonstrate significant potential in removing pollutants like AO7 through synergistic interactions with oxidants, utilizing their exceptional catalytic properties and high surface area for adsorption. However, their effectiveness is limited by a relatively large band gap, which hinders their catalytic performance. This study reveals that Ni/O dual-doped
(NiOCN) effectively optimizes the structure and catalytic performance of
. Experimental results indicate that the NiOCN/peroxymonosulfate (PMS) system exhibits optimal AO7 degradation performance, achieving 92.3% degradation within 10 min while maintaining 80% efficiency in simulated aqueous matrices. Quenching experiments further identified superoxide anion radicals ( ⋅ O 2 − ) as the predominant reactive species governing AO7 degradation. Using density functional theory (DFT) calculations, we confirmed that Ni/O dual-doping narrows the band gap and boosts catalytic activity. Our findings mechanistically demonstrate that Ni/O dual-doping augments PMS activation performance by introducing impurity energy levels, increasing adsorption sites, and accelerating electron migration kinetics.
研究领域:
环境化学
·
材料科学
·
催化反应
·
污染物处理
·
理论计算
·
水污染控制
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Huiyu He,Rongbin Nie,Nan Dong
Biogenic amines (BAs) are the vital indicators of food freshness, and monitoring the change of BAs content is quite essential for food safety. Herein, we developed a matrix solid phase dispersion (MSPD) extraction technology based on cucurbit[7]uril (Q[7]) to extract BAs from pork and shrimp. Then, the extracted BAs were analyzed by capillary electrophoresis (CE) with low sample consumption and high analytical efficiency. The factors affecting MSPD extraction were optimized by Plackett-Burman and the Box-Behnken design (BBD). The limits of detection (LODs) were ranging from 0.003 to 0.019 mg kg −1 , the recoveries of spiked samples were 80.15 %–110.3 %. The satisfactory accuracy and precision were attributed to the host–guest interaction between Q[7] and BAs. Furthermore, the freshness of pork and shrimp was evaluated by simultaneous determination of four BAs. For its wide linear range, high sensitivity, and cost-effectiveness, the proposed Q[7] mediated MSPD-CE-UV provides meaningful potential prospects in the rapid monitor of food freshness and safety.
研究领域:
食品安全
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2023
·Vol. 11
·期 11
·2478-2489
·
IF 7
Yanhao Zhang,Ji Wang,Chao Liu,Hanlei Xing,Yuhao Jiang,Xinsong Li
7-Ethyl-10-hydroxyl camptothecin (SN38), a semisynthetic derivative of camptothecin, exhibited extreme pharmacological activities in treating a range of cancers. However, its poor aqueous solubility and low stability hinder its clinical applications. Hence, a redox-responsive SN38 prodrug encapsulated human serum albumin (HSA) nanoparticle is developed to realize its potential in the clinic. First, a disulfide bond bridged 7-ethyl-10-hydroxyl camptothecin-undecanoic acid conjugate (SN38-SS-COOH) was synthesized and characterized structurally. After that, SN38-SS-COOH/HSA nanoparticles (SNH NPs) were prepared by the desolvation method. The SNH NPs with a feed molar ratio of 9 : 1 of SN38-SS-COOH : HSA showed a spherical structure with a diameter range of approximately 120–150 nm revealed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Fluorescence quenching confirmed the formation of SNH NP complexes by dual hydrophobic force and electrostatic interaction. The SNH NPs have a high drug loading of 10.44% and an encapsulation efficiency of 89.59% with good stability. Moreover, the redox responsiveness was validated by glutathione (GSH)-triggered accelerated release of parent drug SN38. In an in vivo pharmacokinetic study, the SNH NPs exhibited a significantly prolonged circulation time (t1/2, 3.77-fold) compared with free SN38. Finally, the in vivo antitumor efficacy and systemic toxicity of SNH NPs in a breast xenograft model were thoroughly evaluated. The inhibition rate of tumor growth induced by the SNH NPs reached 70.1%, while only 50.1% was achieved for irinotecan at an equivalent SN38 dosage of 10 mg kg−1. More importantly, the SNH NPs achieved a higher level of tumor growth inhibition (85.3%) by increasing the dosage to 60 mg kg−1 SN38 without obvious adverse effects. Taken together, the use of redox-responsive SN38 prodrug/HSA NPs could be a promising strategy to deliver highly active SN38 for breast cancer chemotherapy.
研究领域:
药学
·
肿瘤学
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Chang Liu,Yinuo Wu,Huizhe Zhao,Xiangyu Gu,Jinyang Gu,Mengmeng Zhao,Shangci Zuo,Pengchao Wang
7-Methylxanthine (7-MX), a caffeine (1,3,7-trimethylxanthine) derivative, has gained significant attention as a potential drug for myopia treatment. However, the efficient production of this valuable compound poses challenges: Isolation and chemical synthesis of 7-MX are both difficult to realize due to their poor yields and high costs. Therefore, developing efficient biosynthetic pathways has emerged as a promising alternative strategy. This study aimed to establish an efficient, low-cost, and pollutant-free biosynthetic process for producing 7-MX from caffeine, in which the biosynthetic process is achieved by utilization of ndmA, ndmB, and modified ndmD genes. Moreover, the rich caffeine in coffee waste can be used as an ideal substrate for this reaction, which can reduce the production cost and treat the caffeine in coffee waste residue to promote secondary utilization. By optimizing the gene expression, constructing cofactor regeneration system composed of frmA, frmB, and FDH to regenerate NADH to remove the bottleneck, and engineering Escherichia coli for high-density fermentation, we increased the production of 7-MX to an unprecedented 8.37 g/L. This approach represents the most efficient method thus far for producing 7-MX from caffeine and provides insights into synthesizing other valuable methylxanthines.
研究领域:
生物技术
·
药学
·
代谢工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL ENGINEERING SCIENCE
·
2021
·Vol. 38
·期 12
·1149-1157
·
IF 1.907
Zhimeng Zhang,Yuqin Wang,Feng Jiang,Qingjing Liu,Di Lang
Fenton reaction is extensively used in wastewater treatment to produce •OH, which can be used to remove organic pollutants excellently. However, the greatest issue of the process is the low efficiency of Fe2+/Fe3+ conversion cycle and hydrogen peroxide (H2O2) decomposition rate (<30%). In this study, molybdenum disulfide (MoS2) was used as a co-catalyst in Fenton system to accelerate the oxidation of acid orange 7 (AO7) dye. The enhanced removal efficiency was attributed to that the unsaturated S atoms on the surface of MoS2 could capture the protons in solutions and turn into H2S, exposing the active sites with reducibility and accelerating the conversion of Fe2+/Fe3+. A high degradation rate of 98% was obtained in 30 min under the optimal conditions of AO7 concentration 100 mg/L, MoS2 6 g/L, FeSO4·7H2O 50 mg/L, H2O2 concentration 1.5 mmol/L, and pH 3.5. Furthermore, the degradation pathway and mechanism of AO7 were thoroughly discussed. The toxicity of the intermediates during the degradation progress slightly increased initially, which then decreased to nontoxicity. MoS2 can keep stable, which can maintain high AO7 removal efficiency even after being reused for seven times. Moreover, the obtained results provide a theoretical basis and guidance for the application of inorganic co-catalyst in practical wastewater remediation applications.
研究领域:
环境科学
·
化学工程
✓ 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）