SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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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
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医学检验
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DOI
PubMed
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
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环境科学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2022
·Vol. 46
·期 16
·7695-7703
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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
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
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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
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环境科学
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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
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药学
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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
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环境科学
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产品关联
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
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
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2014
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IF 1.178
Xiao-Lan Li,Dong-Ling Meng,Jiao Zhao,Ya-Ling Yang
This study aimed to establish a rapid analytical method to determine antioxidants in essence. A simple, efficient and practical, vortex-assisted, cloud-point extraction (VACPE) procedure is proposed for extracting and pre-concentrating four different of synthetic phenolic antioxidants (SPAs), propyl gallate (PG), tert -butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) in essence prior to high performance liquid chromatography (HPLC) analysis. The non-ionic surfactant, fatty alcohol polyoxyethylene ether-9 (AEO-9), was used as extractant and vortex-mixing was utilized to reduce extraction time and improve extraction efficiency. The effective parameters of the extraction process, such as volume of extraction solvent, pH, vortex-mixing time, equilibration temperature and time, were optimized. Under the optimum conditions, the linear range of PG, TBHQ, BHA and BHT was 8.0–800 ng/mL. All correlation coefficients of the calibration curves were higher than 0.996 and relative standard deviations (RSD, n = 5) were 2.36%–5.46%. The proposed method was successfully applied to the extraction and determination of antioxidants in essence samples with satisfactory relative recoveries of 89.4%–103.5%. The results confirmed the SPAs of essence could be effectively monitored by this method and also established good reference criteria for essence.
研究领域:
分析化学
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食品科学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHIC SCIENCE
·
2015
·Vol. 53
·期 7
·1169-1177
·
IF 1.363
Zhao Jiao,Wang Jun,Yang Yaling,Lu Yunhui
A simple efficient and practical separation/preconcentration coupled with HPLC method for the determination nitrate and low concentrations of nitrite in human urine and blood was investigated. The method is based on precolumn derivatization using the Griess reaction and cloud-point extraction (CPE) of nitrite anion and direct determination of nitrate using its UV absorbance by ion-pair HPLC. The chromatographic process with detection at two wavelengths (510 and 220 nm) allows the determination of nitrite and nitrate. Decolorization and protein precipitation of urine and blood was applied to overcome the interference of matrix and enhance the sensitivity. The method was validated for linearity, accuracy and precision. Under the optimum conditions, the linear range of nitrite from 10 to 1,000 ng/mL and nitrate from 0.1 to 10 µg/mL. Product recoveries ranged from 92.4 to 99.9%. The limits of detection were 1 ng/mL and 0.1 µg/mL for nitrite and nitrate, respectively. Therefore, the technique was simple and reliable, with potential application in biological sample analysis of nitrate and nitrite.
研究领域:
分析化学
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生物医学
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DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 80
·65321-65327
·
IF 3.84
Chunlei Fan,Shengxu Luo,Rong Liu
In this work, 2′,7′-di(2-benzothiazolyl)-fluorescein (BTF) was synthesized by using 2-(2′,4′-dihydroxyphenyl) benzothiazole (BT) and phthalic anhydride. BTF is colorful and its absorption maximum occurs at 559 nm. Interestingly, the introduction of Cu2+ affords a dramatic decrease of the absorbance at 559 nm, which is due to the spirolactonization of BTF induced by Cu2+. BTF shows high selectivity toward Cu2+ over other common metal ions in real samples, such as K+, Mg2+, Ca2+, Na+, Fe3+, Cd2+, Al3+, Co2+, Cr3+, Mn2+, Ni2+, La3+ and Zn2+. On this basis, a cloud point extraction (CPE) was developed for copper determination by a UV-vis method. The BTF–Cu2+ complex was explored for pre-concentration, and dissolved in a micellar phase composed by octylphenoxypolyethoxyethanol (Triton X-114). Under optimal experimental conditions, the decrease of the absorbance value (ΔA) at 559 nm is linear with Cu2+ concentration in the range from 0.03 to 2 μmol L−1 (1.90–127 μg L−1) with a limit of detection of 7.48 nmol L−1 (3σ). The method has been successfully applied for the determination of copper in tea and water samples.
研究领域:
分析化学
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环境科学
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产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2021
·
IF 4.821
Weiting Liu,Meiyi Xie,Xiaotang Hao,Qian Xu,Xun Jiang,Tiantian Liu,Mei Wang
A novel method was established for preconcentration and determination of the following five polar phenolic compounds: phenol, o -, m -, and p -cresol and 2,4-dimethylphenol. After separating and enriching the analytes by rapid synergistic cloud point extraction (RS-CPE), high performance liquid chromatography (HPLC) was carried out, and the components in surfactant-rich phase supernatant were detected fluorometrically. N-Pentanol, an alcohol with high polarity and rapid cloud point reduction effect, was used as the synergistic reagent, and the straight chain non-ionic surfactant Tergitol 15-S-7 was selected as the extractant. The pH, surfactant, salt concentration, revulsant and synergistic reagent were optimized. Under the optimum conditions, the correlation coefficients among target substances were all>0.998. The relative standard deviation range was 1.7%–5.0%, and the detection limit range was 0.061–0.166 μg/L. The proposed method is simple, economical, highly efficient and sensitive. It was successfully applied to the extraction and determination of polar phenolic compounds in environmental water samples, and the recoveries ranged from 85.6% to 108%.
研究领域:
分析化学
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环境科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Xin Ge,Weili Song,Xinzhi Chen,Chao Qian,Shaodong Zhou,Xuemin Liu
A tandem process of micellar catalysis and cloud point extraction (CPE) is developed for copper-catalyzed Ullmann C-S coupling reactions in water. The functional nonionic surfactant, amine terminated polyether M2070, affords nano-micelle environment in the aqueous system; the latter splits to two phases above the cloud point temperature (CPT). The nature of the micellar catalysis in M2070 aqueous was investigated by DLS, EDS, XPS, IR, TEM and 1 H NMR. M2070 was verified to provide nano-space for encapsulation and aggregation of the substrates. More importantly, the metallic micelle formed by M2070 chelating copper was identified. It is noteworthy that excellent productivity in pre-micellar catalysis of C-S coupling reactions was obtained with good tolerance of substrate. Finally, the water-micelle system was separated into two phases above the CPT thus to achieve the product separation. Furthermore, the M2070/water system can be recycled and reused.
研究领域:
化学工程
·
催化化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）