SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2014
·
IF 2.129
Jiao Zhao,Yunhui Lu,Chongyang Fan,Jun Wang,Yaling Yang
A novel and simple method for the sensitive determination of trace amounts of nitrite in human urine and blood has been developed by combination of cloud point extraction (CPE) and microplate assay. The method is based on the Griess reaction and the reaction product is extracted into nonionic surfactant Triton-X114 using CPE technique. In this study, decolorization treatment of urine and blood was applied to overcome the interference of matrix and enhance the sensitivity of nitrite detection. Multi-sample can be simultaneously detected thanks to a 96-well microplate technique. The effects of different operating parameters such as type of decolorizing agent, concentration of surfactant (Triton X-114), addition of (NH 4 ) 2 SO 4, extraction temperature and time, interfering elements were studied and optimum conditions were obtained. Under the optimum conditions, a linear calibration graph was obtained in the range of 10–400 ng mL −1 of nitrite with limit of detection (LOD) of 2.5 ng mL −1 . The relative standard deviation (RSD) for determination of 100 ng mL −1 of nitrite was 2.80%. The proposed method was successfully applied for the determination of nitrite in the urine and blood samples with recoveries of 92.6–101.2%.
研究领域:
分析化学
·
医学检验
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产品关联
DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2025
·
IF 2.7
Yanling Yang,Yining Shi,Yue Shi
Smart windows with adjustable optical properties for energy-saving applications have received increasing attention. In this study, an anisotropic single-domain structure is successfully prepared by shearing-oriented hydroxypropyl cellulose (HPC) in poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) hydrogel network. This composite hydrogel can respond to ambient temperature and solar radiation in the visible and near-infrared light regions for smart window applications. By precisely controlling the component of the composite hydrogel, the cloud point temperature ( T cp ) of the smart window can be significantly tuned from a very high value to below the comfortable temperature for the human body. For example, with 10 wt.% PAMPS and 42 wt.% HPC, the crosslinking hydrogel demonstrates a stable single-domain structure and relatively low T cp . With the addition of NaCl, T cp can be further reduced to even below the human comfort temperature. The oriented composite hydrogel showed excellent durability, flexibility, and thermal radiation shielding under the sunlight simulator with tunable T cp . These properties make the HPC/PAMPS composite hydrogel have a broad application prospect in the realm of energy-efficient building smart windows and effectively improve the comfort of indoor environments with different demands.
研究领域:
材料科学
·
能源技术
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DOI
高影响因子
ANALYTICAL LETTERS
·
2024
·
IF 1.6
Yanli Yu,Guangming Zhou,Ziyi Huang
A novel method has been developed for accurately quantifying arsenic species, including As(III), As(V), and total inorganic arsenic, in drinking water. The technique combines ultraviolet-visible spectrophotometry with cloud point extraction (UV/CPE), ensuring high sensitivity and selectivity. The methodology relies on complex formation between As(III) and Pyronin B in the presence of tartaric acid. The resulting complex is efficiently extracted into the surfactant-rich phase consisting of 5.0% (v/v) Triton X-114. Under optimized conditions, a linear calibration relationship from 3 to 500 µg/L is obtained. The method offers low detection and quantification limits of 1.04 and 3.48 µg/L, respectively, with a corresponding relative standard deviation below 5% for 11 replicates. Furthermore, spiked samples demonstrated excellent recovery values from 95.1% to 102.3%. The accuracy was verified by the analysis of the standard reference material SRM 1643e (trace elements in water), revealing no significant differences at the 95% confidence level. The approach was successfully utilized for the quantification of As(III), As(V), and total inorganic arsenic in commercial and domestic drinking water.
研究领域:
分析化学
·
环境科学
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DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 90
·49028-49039
·
IF 3.708
Peng Liu,Jiexing Liang,Shen Chen,Hailiang Zhang
A series of thermo-responsive rod–coil diblock copolymers with well-defined molecular weights have been synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The rod–coil diblock thermo-responsive copolymer studied herein is poly(N-isopropylacrylamide)-b-poly[bis(N-hydroxyisopropyl pyrrolidone) 2-vinylterephthalate] (PNIPAm-b-PHIPPVTA), in which PHIPPVTA is a thermo-responsive rod-like polymer and exhibits an MW-dependent liquid crystalline (LC) phase behavior and MW-dependent thermo-responsive behavior. The bulk phase behaviors of the copolymers have been investigated by a combination of techniques including differential scanning calorimetry (DSC), polarized light microscopy (PLM), 1D and 2D wide-angle X-ray diffraction. The experiment results demonstrated that the phase structure of PNIPAm-b-PHIPPVTA is a hexatic columnar nematic phase when N43bHx and N151bHx with x ≥ 95 and 146, respectively. The thermo-responsive behaviors were investigated with turbidity measurements using UV-visible spectroscopy. The results showed that the cloud point of the diblock copolymers PNIPAm-b-PHIPPVTA can be adjusted by varying the length of the PHIPPVTA block. Only one phase transition temperature has been observed in the thermo-responsive rod–coil diblock copolymer PNIPAm-b-PHIPPVTA. Of special interest is the cloud point of block copolymers with longer flexible chain segment more strongly depending on the length of the semirigid segment compared to copolymers with shorter flexible chain segment.
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 16
·7695-7703
·
IF 3.925
Qi Wu,Changfeng Zhao,Qinzhong Wang,Jing Liu
This study proposes the efficient separation of Au(III)/Pd(II)/Pt(IV)/Rh(III) through the 2-mercaptobenzothiazole-functionalised ionic liquid ([C6mim][2MBT]) using a cloud point extraction system. Direct cloud point extraction of Au(III) (about 99.9%) was realised without involving any functionalised ionic liquids. A significant enhancement of the Pd(II) extraction performance was found by adding rationally constructed [C6mim][2MBT]. Consequently, a fairly high extraction percentage of about 99.4% was obtained. However, further advancement of the proposed cloud point extraction showed that it could not be applied for the preconcentration of Pt(IV) and Rh(III) without adding stannous chloride, which plays a critical role in the segregation and could be adjusted by changing the hydrochloric acid concentration. Under the optimised conditions, the Rh(III) extraction process shows a high yield percentage (ca. 83.0%), where the majority of Pt(IV) was enriched in the aqueous phase. In addition, the underlying possible extraction mechanism was investigated using UV-vis, FT-IR and TEM measurements, which indicated that TX-114 acted as a solvent for the extracted metals. The developed procedure reveals efficient direct Au(III)/Pd(II)/Pt(IV)/Rh(III) separation using [C6mim][2MBT] via cloud point extraction.
研究领域:
分析化学
·
环境科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Hong Zhang,Xiaoyu Yang,Zhaohui Liu,Yanzhao Yang
An arisen and environment-friendly method of cloud point extraction (CPE) which involved Octylphenoxypolyethoxyethanol (TX-114) as surfactant and 2-Mercaptobenzothiazole-functionalized ionic liquid as extractant was carried out to separate Ru(III) from aqueous phase to bottom surfactant phase for the first time. A host of variable ( e.g. , the extractant concentration, hydrochloric acid concentration, nitric acid concentration, TX-114 mass fraction, TX-114 volume and sodium chloride concentration) were evaluated and optimized to investigate the extraction behavior. At optimized experimental conditions, the extraction percentage of Ru(III) was found to be 82%, together with the enrichment factor of 40. A special complexation extraction mechanism of Ru(III) in CPE process was studied systemically and confirmed via job method, UV–vis spectrum and FT-IR spectrum in detail. Taking together, the rational-designed functional ionic liquid as a novel extractant exhibited superior extractability for Ru(III) in CPE system.
研究领域:
化学
·
环境科学
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DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2016
·Vol. 295
·期 2
·307-315
·
IF 1.89
Jong Kwanghyok,Ju Benzhi
Thermo-responsive polymers present great advantages in the targeted delivery and release of drugs. In this study, a novel type of thermo-responsive polymer called 2-hydroxy-3-(2-propynyloxy) propyl hydroxyethyl starch (PyHES) was synthesized via hydrophobic modification of hydroxyl groups in hydroxyethyl starch (HES) with 2- propynylglycidyl ether (PGE). Aqueous PyHES solutions with an appropriate degree of substitution (DS) of hydrophobic propynyl groups exhibited strong thermo-responsive properties as well as a cloud point temperature (Tcp) that could be tuned within a range of 31 to 48 °C by changing the DS or PyHES concentrations. Moreover, the Tcp decreased with increases in the DS or the concentration of PyHES. The Tcp of PyHES had a linear relationship with DS, and DLS characterizations indicated that PyHES can form thermo-responsive micellar nanoparticles in aqueous solutions. In addition, PyHES can be further functionalized via click reaction of the propynyl group.
研究领域:
材料科学
·
生物医学工程
·
药物递送系统
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DOI
高影响因子
Polymer Chemistry
·
2017
·Vol. 8
·期 37
·5749-5760
·
IF 5.375
Hongcan Zhang,Jian Zhang,Wenxue Dai,Youliang Zhao
The simple and straightforward construction of multi-responsive systems with tunable LCST and UCST dual phase transitions is a great challenge. This study affords an efficient route to tune cloud points via control over the chemical composition of hydroxyl and diethylamino bearing poly(amido thioether)s which were prepared by one-pot thiol–amine–acrylate polyaddition. Owing to the balance of inter/intrachain interactions, various copolymers could exhibit LCST (fOH < 0.84), LCST–UCST (fOH = 0.84–0.89) and UCST (fOH > 0.89) behaviors relying on the hydroxyl fraction in comonomer units. Meanwhile, the thermoresponsive behaviors of copolymer solutions could be efficiently tuned via switching the solvent and solution pH, applying CO2/N2 bubbling, and oxidation. The success of this study further paves the way for the robust synthesis and practical applications of smart polymers with double thermoresponsivity.
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
Journal of the Iranian Chemical Society
·
2013
·Vol. 11
·期 2
·415-422
·
IF 1.467
Zou Deqing,Qing Ye,Li Yingtang,Liu Mosheng,Yang Yaling
A highly sensitive method for the determination of manganese (VII), chromium (VI) and nickel (II) in medicinal herb samples is proposed. The method is based on analytes reacted with ammonium pyrrolidinedithiocarbamate (APDC) to give hydrophobic chelates (M–APDC), which were separated and enriched by cloud-point extraction (CPE) with non-ionic surfactant Tergitol TMN-6 as extractant. The surfactant-rich phase containing the chelates is determined with a high-performance liquid chromatography system. To achieve the best CPE method, the Box–Behnken design was used to study the concentration of Tergitol TMN-6, equilibrium temperature, equilibrium time as well as their interaction. What followed was the individual research for the pH of the sample solutions and the concentration of APDC. What is more, in the given optimized experimental conditions, calibration plots were found to be linear in the range of 0.0200–0.500 mg/L for Mn (VII) and Cr (VI), meanwhile 0.0500–1.00 mg/L for Ni (II), the linear correlation coefficients were between 0.996 and 0.999, the recoveries ranged from 91.8 to 97.8 % and the relative standard deviations were between 1.09 and 2.30 % ( n = 3). The limits of detection were 0.164 μg/L for Mn (VII), 0.562 μg/L for Cr (VI) and 5.12 μg/L for Ni (II), respectively. The proposed method was applied to determine manganese (VII), chromium (VI) and nickel (II) in medicinal herb samples with satisfactory results.
研究领域:
分析化学
·
药学
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DOI
高影响因子
SAUDI JOURNAL OF BIOLOGICAL SCIENCES
·
2017
·
IF 2.564
Xiupei Yang,Zhihui Jia,Xiaocui Yang,Gu Li,Xiangjun Liao
A cloud point extraction (CPE) method was used as a pre-concentration strategy prior to the determination of trace levels of silver in water by flame atomic absorption spectrometry (FAAS) The pre-concentration is based on the clouding phenomena of non-ionic surfactant, triton X-114, with Ag (I)/diethyldithiocarbamate (DDTC) complexes in which the latter is soluble in a micellar phase composed by the former. When the temperature increases above its cloud point, the Ag (I)/DDTC complexes are extracted into the surfactant-rich phase. The factors affecting the extraction efficiency including pH of the aqueous solution, concentration of the DDTC, amount of the surfactant, incubation temperature and time were investigated and optimized. Under the optimal experimental conditions, no interference was observed for the determination of 100 ng·mL −1 Ag + in the presence of various cations below their maximum concentrations allowed in this method, for instance, 50 μg·mL −1 for both Zn 2+ and Cu 2+ , 80 μg·mL −1 for Pb 2+ , 1000 μg·mL −1 for Mn 2+ , and 100 μg·mL −1 for both Cd 2+ and Ni 2+ . The calibration curve was linear in the range of 1–500 ng·mL −1 with a limit of detection (LOD) at 0.3 ng·mL −1 . The developed method was successfully applied for the determination of trace levels of silver in water samples such as river water and tap water.
研究领域:
分析化学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2016
·Vol. 34
·期 12
·1436-1447
·
IF 1.811
Fu Xiao-hui,Ma Yi-nan,Sun Jing,Li Zhi-bo
A series of poly( L -glutamate)s grafted with oligo(ethylene glycol) (OEG) side-chains through the thioether linkages (PALG
n
- g -EG
x
, x = 2, 3 and 4) were prepared by ring-opening polymerization (ROP) of γ-allyl- L -glutamate N -carboxyanhydride (ALG-NCA) and thiol-ene photoaddition. The chemical structures and physical properties were characterized by 1 H-NMR, Fourier transform infrared (FTIR), circular dichroism (CD), etc . The PALG
n
-g-EG
x
samples with x = 3 and 4 displayed lower critical solution temperature (LCST) in water due to the presence of OEG units. The clouding point (CP) of polypeptides can be finely tuned by changing the side chain structures, molecular weights and sample concentrations. In addition, the thioether linkages in the side chains offer additional redox-responsive properties. The influence of both OEG units and thioether linkages on the LCST behavior was systematically investigated. This work provides an efficient way to prepare multi-stimuli responsive materials with highly tunable properties.
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
Analytical Methods
·
2014
·Vol. 6
·期 10
·3285-3290
·
IF 1.938
Yingtang Li,Chao Yang,Jinyan Ning,Yaling Yang
In this work, cloud point extraction (CPE) was developed for the preconcentration and separation of bisphenol A (BPA), bisphenol AF (BPAF) and tetrabromobisphenol A (TBBPA) prior to high-performance liquid chromatography (HPLC) analysis. Firstly, alcohol ethoxylate (AEO9) was applied as the extractant and octanol worked as the cloud point revulsant and synergic reagent for extraction, which decreased the cloud point temperature (CPT) of AEO9 from 75 °C to 30 °C and assisted the subsequent extraction. The parameters influencing the CPE efficiency, such as AEO9 concentration, octanol volume, pH value, extraction time and temperature were systematically evaluated. Under the optimum conditions, the linear range of BPA, BPAF and TBBPA was from 0.05 to 25 mg L−1. All correlation coefficients of the calibration curves were more than 0.9988. The relative standard deviations (RSD, n = 5) were 1.6–4.7%. The limits of detection (LOD) were in the range of 0.27–0.32 μg L−1 and the limits of quantification (LOQ) were in the range of 0.71–0.98 μg L−1. The proposed method was successfully applied to the extraction of BPA, BPAF and TBBPA in river water samples as a rapid, simple, and sensitive method.
研究领域:
分析化学
·
环境科学
✓ 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）