JOURNAL OF LIQUID CHROMATOGRAPHY & RELATED TECHNOLOGIES
·
2020
·
IF 0.992
Jian-Sha Li,Dan Huang,Hong-Mei Qiu,Qing-Song Jiang,Yong-Hong Liu,Ting-Ting Du,Xin-Hui Jiang
A high-performance liquid chromatography-electrochemical detection method was developed to determine the concentration of homocysteine and cysteine in the diabetes mellitus Sprague-Dawley male rats’ cortex and hippocampus. The cortex and hippocampus of control and diabetes model rats were collected. After pretreatment, the analysis of total homocysteine and cysteine were performed on a C8 column. Under the optimized analytical conditions, the linear correlation coefficients were higher than 0.999 in the concentration range from 0.148 to 22.193 μmol.L−1 with the limit of quantitation of 0.083 μmol.L−1. The extraction recoveries of Hcy and Cys from spiked samples were 90.87–100.25%, and the relative standard deviations (RSD %) were 1.56–9.13%. The established method is simple, accurate, sensitive, and suitable for the separation and determination of Hcy and Cys in biological samples. Compared with the control group, the concentrations of Hcy and Cys in the diabetes group were different in the cortex. The difference suggests that changes in the levels of the two substances may be associated with complications of diabetes mellitus.
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高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Jiangping Cao,Qilong Xie,Hongwei Di,Yongfeng Liang,Gui Ma,Zonghui Yi,Ping Zhang,Peng Fu,Jikai Li
A method for the simultaneous determination of eight phenolic compounds (PCs) with a wide polarity range in water samples has been developed and validated using molecular complex based dispersive liquid–liquid microextraction (MC-DLLME) followed by high-performance liquid chromatography. In this process, the molecular complex acted as the extractant, which was formed by tributyl phosphate (TBP) and 1-octanol through hydrogen bond interaction in situ, using a disposable polyethylene pipette for the extraction. The extraction mechanism was investigated by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), which demonstrated that a TBP-1-octanol complex formed via P O HO hydrogen bonding . Furthermore, the extraction mechanism in the dual extraction solvent system involves hydrogen bonding for polar PCs and physical extraction for weak polar and apolar ones. Under the optimum conditions, detection limits were in the range 0.4–5.51 ng/mL and recoveries for the real samples varied from 82.0% to 104.7%, with a relative standard deviation (RSD) of <9.1%. The developed method is simple, inexpensive and sensitive and was successfully applied to the extraction and determination of phenolic compounds in water samples.
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高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Tian Yao,Kaifeng Du
Four novel organic magnetic ionic liquids were synthesized and characterized. A new method of in-situ magnetic ionic liquid dispersive liquid-liquid microextraction coupled with HPLC was established to simultaneously separate, preconcentrate and determine trace amount of sulfonamides in milk samples for the first time. In this work, extraction procedure was free of volatile organic solvent. Extraction equilibrium was immediately achieved without further operation such as vortex shaking. Magnetic separation of two phases was effectively achieved by applying external magnetic field without need of centrifugation. Furthermore, only a very small amount of inorganic salts were generated. This is the first time to realize all these advantages in an analytical method. Under the optimal conditions, satisfactory enrichment factors, precisions, linear range and low limit of detection and quantitation were acquired. The validated method was successfully applied in the simultaneous analysis of 5 sulfonamides in real milk samples.
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高影响因子
FERROELECTRICS
·
2020
·
IF 0.669
Chen-Qi Zhang,Qiao-Hong Peng,Song Wang,Lin Guo,Hai-Lin Cong,You-Qing Shen,Bing Yu
High-performance liquid chromatography (HPLC) is one of the most widely used separations and analysis methods, which has become an indispensable part of the separation and detection of mixtures, qualitative and quantitative analysis and other scientific research and social production fields. Because of the decisive effect of the chromatographic column on analysis and separation, it has become the core of research in the chromatographic system. In the past decades, the research and development of new chromatographic column stationary phase have been highly concerned. Monodisperse polymer microsphere, because of its special large pore structure, has good permeability and high specific surface area, which can be used as special materials in various fields, such as adsorption materials in the separation process, HPLC column packing, catalyst carrier, preparation template of nanomaterials and nuclear fusion targeting materials. When it is used in HPLC, because of the good permeability of microspheres, it can effectively improve the separation efficiency and performance. In this article, based on the previous work, a number of new polymer microspheres were prepared, and the prepared microspheres were used for the separation and detection of HPLC, and their physical and chemical properties were studied.
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高影响因子
MICROCHEMICAL JOURNAL
·
2020
·
IF 3.594
Dan Wang,Yuanchen Liu,Zhigang Xu,Dandan Zhao,Yujian Liu,Zhimin Liu
Molecularly imprinted polymers (MIPs) usually show specific selectivity to a single template molecule and its structural analogs. But how about the selectivity is when multitemplates are used to obtain MIPs? Herein, ethyl p -hydrobenzoate (EP), bisphenol A (BPA) and dibutyl phthalate (DBP) were used as template molecules to synthesize triple-template MIP (TMIP). The adsorption properties of the TMIP for three types of endocrine disruptors (EDCs) in environmental water samples were then examined. For comparison, three single-template molecularly imprinted polymers (SMIPs), three dual-template molecularly imprinted polymers (DMIPs), and a non-imprinted polymer (NIP) were synthesized through the same procedure for TMIP synthesis. DMIP using EP and DBP as templates showed the best selectivity and extraction amounts for EDCs among all MIPs, including TMIP. It was successfully used for EDCs analysis in environmental water samples. The linear range of was 0.1–125 μg L −1 . The limit of detection was 0.03 μg•L −1 . The recovery ranged from 87% to 120%, and the RSD% ( n = 5) was less than 10%. Most importantly in the preparation of multitemplate MIPs, competition was observed between two or more template molecules and the monomer. Therefore, additional template molecules for multitemplate MIPs that do not weaken the previous template-monomer interactions might be considered.
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高影响因子
FERROELECTRICS
·
2021
·
IF 0.62
Qi Tang,Long-Xiang He,Xiao-Kun Chu,Bing Yu,Xiang-Ling Gu,You-Qing Shen,Hai-Lin Cong
A novel chiral selector polyacrylic acid-β-cyclodextrin (PAA-β-CD) was successfully prepared, then a facile synthesis of PAA-β-CD stationary phase based on diazotized silica was developed and characterized. Monodisperse silica microspheres were synthesized by a modified Stöber method. The obtained silica particles were functionalized by self-assembly positive charged photosensitive diazoresin (DR) and PAA-β-CD on the surface. The corresponding chiral stationary phase (CSP) was used in HPLC and the enantioseparation performance was investigated in both polar organic and reverse phase mode. Better separation abilities and excellent enantio-selectivities were obtained on PAA-β-CD CSP for antihistamine drugs in the acetonitrile and triethylammonium acetate buffer mobile phase. Abbreviations: AIBN: azodiisobutyronitrile; β-CD: b-cyclodextrin; β-CD-NH2: amino-β-CDcyclodextrin; β-CD-OTs: sulfonyl-b-cyclodextrin; CD: cyclodextrin; CSP: chiral stationary phase; DCC: dicyclohexyl carbimide; DR: diazoresin; MeOH: methanol; NMP: N-methyl pyrrolidone; PAA: polyacrylic acid; PAA-β-CD: polyacrylic acid-β-cyclodextrin; TEAA: triethylammonium acetate; TEOS: tetraethyl orthosilicate
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高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 2
·1-8
·
IF 5.479
Ding Hui,Wang Rongyu,Liu Wei,Cheng Supan,Ji Wenhua,Zheng Zhenjia,Wang Xiao
The authors describe a new spherical metal-organic coordination polymer (MOCP) for use as an adsorbent in solid-phase microextraction (SPME). By applying the ions Co(II), Fe(II), Cu(II), and Zn(II) in these polymers, MOCP with different morphology were obtained. The respective coatings for SPME display different extraction efficiency towards neonicotinoid insecticides (neo-nics). The Co(II)@MOCP coating displays an improved extraction capability for neo-nics when compared to the four commercially available coatings studied. Following extraction with the Co(II)@MOCP-coated fiber, the neo-nics were eluted using 1 mL of trifluoroacetic acid/acetonitrile solution and quantified by high performance liquid chromatography. The method, when applied to spiked honey samples, has good linearity (0.5–600 μg kg −1 ) and a low limit of detection (0.05–0.15 μg kg −1 ). The precision ( n = 6) for a single fiber was in the range of 3.6–8.3%. The reproducibility (for n = 5) from fiber-to-fiber ranges between 5.4 and 8.8%. The Co(II)@MOCP-coated fiber can be reused more than 80 times without any apparent reduction in its performance. In addition, the relative recoveries from spiked honey samples are very good (91.5%–103.5%).
A spherical metal-organic coordination polymer (MOCP) was synthesized under the regulation of Co(II) and used for the solid-phase microextraction (SPME) of neonicotinoid insecticides found in honey.
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高影响因子
MICROCHEMICAL JOURNAL
·
2019
·
IF 3.206
Lanyun Fang,Yumei Zhang,Beibei Lu,Li Wang,Xunping Yao,Ting Ge
The present paper proposed an analytical method for speciation analysis of inorganic antimony in inhalable particulate matter, PM2.5, using high performance liquid chromatography coupling with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). A new extraction method consisted of reducing extraction and oxidizing extraction using EDTA as the key component in the extractant has obtained better extraction yield and preserves stability of both species during the extraction process. Stability of Sb species in EDTA-saturated nitric or tartric acid solution and in aqueous solution were carefully investigated. Using the optimized conditions, the method allows for the determination of Sb(III) and Sb(V) in PM2.5 samples with limits of 0.10 and 0.06 ng m −3 , respectively. The precision, expressed as relative standard deviation (RSD), was always lower than 8.5% and 6.6% for Sb(III) and Sb(V), respectively. The spiked recovery rates of Sb species at three different concentration levels were in the range of 90.0–110.0%. The extraction yield of the sequential extraction process confirmed by analysis of a certified reference material of urban particulate matter, NIST1648a, furnished by National Institute of Standards and Technology was 60%. This method was applied to determine Sb(III) and Sb(V) in PM2.5 samples collected in urban area in Ningbo City, China. The results showed that both Sb(V) and Sb(III) were found in most of the samples analyzed, Sb(V) being the main one, which represents 69–87% of the total Sb extracted in the considered samples, whereas Sb(III) represents the remaining 13–31%.
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高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 6
·1-10
·
IF 5.479
Liu Zikai,Lin Xiwen,Liu Xinya,Li Jing,Zhou Wenfeng,Gao Haixiang,Zhang Sanbing,Lu Runhua
A magnetic sorbent was fabricated by covalently grafting hyperbranched polyamidoamine onto the surface of Fe 3 O 4 nanoparticles. The sorbent was used in the magnetic solid-phase extraction (MSPE) of benzoylurea insecticides (BUs) from environmental water samples. It is perceived that hydrogen bonding interactions and hydrophobic interactions are the main mechanisms for the adsorption of BUs. The sorbent was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, elemental analysis, Brunauer-Emmett-Teller measurement, X-ray photoelectron spectroscopy, vibrating sample magnetometry and X-ray diffraction. Various experimental parameters affecting the MSPE were optimized. Following elution with acetonitrile, the BUs were quantified by HPLC with diode array detection. The method based has a wide linear response range (2.5–500.0 ng mL −1 ), satisfactory coefficient of determination (0.9922–0.9976), high enrichment factors (62.8–74.4), acceptable limits of quantitation (2.5 ng mL −1 ) and low limits of detection (0.39–0.72 ng mL −1 ). The intra-day precision at concentration levels of 5.0, 50.0 and 250.0 ng mL −1 ranged from 2.3–6.4% and the inter-day precision was between 1.0 and 5.5%. The sorbent can be re-used at least 15 times. It was applied to the extraction of BUs from genuine water samples where it showed satisfactory relative recoveries (75.1–111.4%) and precision (1.0–9.1%).
Schematic presentation of magnetic nanoparticles modified with hyperbranched polyamidoamine and their application for extraction of benzoylurea insecticides.
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高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Si-Jin Liu,Juan-Juan Xu,Chang-Lu Ma,Chun-Feng Guo
The six biogenic amines in sausage and cheese were analyzed by HPLC with UV detection after off-line derivatization with dansyl chloride, 9-fluorenylmethoxycarbonyl chloride, benzoyl chloride and dabsyl chloride, respectively. The results showed that both the off-line 9-fluorenylmethoxycarbonyl and dabsyl derivatization were not suitable for HPLC analysis of biogenic amines when batch injection was used because the derivatives were instable, whereas both the off-line dansyl and benzoyl derivatization were suitable for HPLC analysis of biogenic amines when batch injection was used, but the latter needed to maintain the derivatives at 4 °C to ensure that benzoylated tyramine was not degraded when waiting for the analysis. The off-line dansyl derivatization had an obvious advantage in the analysis of biogenic amines in sausage and cheese samples by HPLC combined with batch injection because the method has a wider linear range and higher sensitivity, accuracy, precision and stability of the derivatives.
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高影响因子
TALANTA
·
2018
·
IF 4.244
Xiao Sun,Jing Li,Li Xu
In the present study, the narrow-dispersed penetrable poly(methacrylic acid- co -ethylene glycol dimethacrylate) (poly(MAA- co -EDMA)) microspheres were successfully synthesized based on the sacrificial support method. The poly(MAA- co -EDMA) microspheres mirrored the porous structure of the sacrificial support, i.e. penetrable silica, characteristic of copious mesopores and throughpores. In addition, they possessed large surface area, adjustable hydrophobicity and the cation-exchange ability. Owing to their multi functionalities, they were applied as chromatographic stationary phase to separate proteins in different separation modes, including reversed phase, hydrophobic interaction and weak cation exchange. Moreover, thanks to their throughpores, fast separation at low column backpressure could be achieved in these three modes. Both protein recovery and column stability were satisfactory. The penetrable poly(MAA- co -EDMA) microspheres were potential stationary phase matrix for fast protein separation.
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高影响因子
CHROMATOGRAPHIA
·
2013
·Vol. 76
·期 7
·409-417
·
IF 1.437
Li Chenyu,Chen Ligang
A simple and fast method based on magnetic separation for extraction of pyrethroid pesticides including beta-cyfluthrin, cyhalothrin and cyphenothrin from environmental water samples has been established. Magnetic titanium dioxide was used as sorbent, which was synthesized by coating TiO 2 on Fe 3 O 4 in liquid-state co-precipitation method. The sorbent has been characterized by scanning electron microscopy and Fourier-transform infrared spectrometry, and the magnetic properties were investigated with physical property measurement system. Various parameters affecting the extraction efficiency were evaluated to achieve optimal condition and decrease ambiguous interactions. The analytes desorbed from the sorbent were detected by high performance liquid chromatography. Under the optimal condition, the linearity of the method is in the range of 25–2,500 ng L −1 . The detection limits and quantification limits of pyrethroid pesticides are in the range of 2.8–6.1 ng L −1 and 9.3–20.3 ng L −1 , respectively. The relative standard deviations of intra- and inter-day tests ranging from 2.5 to 7.2 % and from 3.6 to 9.1 % were obtained. In all three spiked levels (25, 250 and 2,500 ng L −1 ), the recoveries of pyrethroid pesticides were in the range of 84.5–94.1 %. The proposed method was successfully applied to determine pyrethroids in three water samples. Cyphenothrin was found in one river water near farmlands, and its concentration was 52 ng L −1 .
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高影响因子
危险品化学品经营许可证（带存储）