Mousheng Liu

Kunming University of Science and Technology, Yün-nan, Yunnan, China

Are you Mousheng Liu?

Claim your profile

Publications (22)30.18 Total impact

  • Xuan Zhou · Yu Zhao · Shuangqiao Ju · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: A safe, rapid, simple and environmentally friendly method based modified corn silk fiber (MC), chemical modified with succinic anhydride (C4H4O3), was developed for the extraction and preconcentration of As(III) in food additives soil alkali sample prior to graphite furnace atomic absorption spectrometry (GFAAS) analysis. The structure and properties of VC (unmodified corn silk fiber) and MC were analyzed and discussed by means of FTIR, SEM and TG, and the effect of adsorbent amount, pH, soil alkali solution concentration, adsorption time and adsorption temperature were carefully optimized. Under the optimum conditions, the relative standard deviations (RSD, n=6) were1.27-3.05%, the calibration graph was linear in the range of 0-100ug/L and the limits of detection (LOD) was 0.13 mu g/L. The surface of MC became loose and porous which increased the adsorption area. Comparing with VC, carboxy groups were measured in MC and the increase of negative electron group in fiber molecular made its coordination combining ability with As(III) enhanced; In comparison with the removal arsenic rate of VC, MC's significantly increased by 2.86 fold. The recovery rate of soil alkali, treated by VC and MC, reached to 96.85% and 94.32%, and it did not affected the function of soil alkali.
    No preview · Article · Oct 2015 · Journal- Chemical Society of Pakistan
  • Shuangqiao Ju · Mousheng Liu · Yaling Yang

    No preview · Article · Sep 2015 · Analytical Letters
  • Xuan Zhou · Pingyan Wang · Yu Zhao · Shuangqiao Ju · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: A simple, safe and rapid method on the basis of cloud point extraction(CPE) with tergitol TMN-6 had been used for the preconcentration and extraction of gold(Au) ion in selenium reduction solution sample prior to flame atomic absorption spectrometry (FAAS). Pyrrolidine dithio fromic acid salt(PDFAS)which was regarded as a selective complexing agent could formed stable Au-complex with Au ion, and Au-complex could be extracted by TMN-6 at a short time. Some influencing factors such as sample pH, concentration of TMN-6, concentration of PDFAS and the effect of foreign ions were further researched. Under the optimum conditions, the limit of detection(LOD) was 1.3μg L-1, the calibration graph was linear in the range of 0-500μg/L and the relative standard deviation(RSD%) was 2.0%(n=8). The CPE method had been shown to be a useful and effective methodology for the separation of Au, with a preconcentration factor of 30. The recoveries of the spiked Au(□) ions were got in the range 95-103%.
    No preview · Article · Aug 2015 · Journal- Chemical Society of Pakistan
  • [Show abstract] [Hide abstract]
    ABSTRACT: Multiwalled carbon nanotubes were modified by Fe3O4 nanoparticles with application for the preconcentration of metals. The modified materials were characterized by infrared spectroscopy, transmission electron microscopy, and X-ray diffraction. The Fe3O4 nanoparticle modified multiwalled carbon nanotubes were used as sorbents for the extraction of cadmium and lead from maca prior to analysis by flame atomic absorption spectrometry. The amount of nanoparticles, pH, adsorption time, coexisting ions, eluent solution, and reuse of the material were characterized to optimize the recoveries of the analytes. Under the optimum conditions, the calibration curves were linear from 0.05 to 20 milligrams per liter for cadmium and from 0.05 to 25 milligrams per liter for lead. The limits of detection were 0.32 and 0.57 micrograms per liter while the relative standard deviations were 2.1 and 1.9 percent, respectively. The method was employed for the determination of cadmium and lead in maca and recoveries between 94.8 and 105.6 percent were obtained.
    No preview · Article · Jul 2015 · Analytical Letters
  • Shuangqiao Ju · Yaling Yang · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: A method for magnetic solid-phase extraction was developed for the preconcentration of bisphenol A, bisphenol AF, tetrabromobisphenol A, and 4-tert-octylphenol from food containers and packaging materials. Cetyltrimethylammonium bromide was added to a solution of magnetic nanoparticles to enhance adsorption of the analytes prior to high-performance liquid chromatography. The effects of the amount of surfactant, the amount of magnetic nanoparticles, the pH, the adsorption time, the desorption solution, and the reuse of the extractant were optimized. The linear dynamic ranges were from 0.05 to 25 milligrams per liter. The limits of detection were between 1.21 and 2.48 micrograms per liter, the limits of quantification were from 4.03 to 8.27 micrograms per liter, and the relative standard deviations were between 2.2 and 4.1 percent. This magnetic solid-phase extraction approach was successfully employed for the analysis of plastics with recoveries from 88.0 to 101.1 percent and relative standard deviations between 2.3 and 5.4 percent.
    No preview · Article · May 2015 · Analytical Letters
  • Tao Luo · Yingtang Li · Chang Liu · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: A simple, safe, environmentally friendly, rapid and inexpensive method based on supramolecular dispersive liquid-liquid microextraction (SM-DLLME) was developed for the preconcentration and separation of copper in water samples prior to flame atomic absorption spectrometry analysis. The 1-(2-thiazolylazo)-naphthol was selected as chelating reagent to react with copper, and the supramolecular solvent which was proposed for dispersing and extracting solvent was made up of nonanoic acid, tetrahydrofuran and water. Some influential factors affecting the analytical performance were studied. Under the optimum conditions, the calibration graph was linear in the range of 10-800 ìg L-1, the limit of detection (LOD) was 0.3 μg L-1for copper, the relative standard deviations (RSD, n = 6) was 2.6 %, respectively. The satisfactory relative recoveries (93.5-101.5 %) were achieved after the determination of copper in water samples.
    No preview · Article · Aug 2014 · Asian Journal of Chemistry
  • Zonghao Li · Jiaxi Chen · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A new method based on ultrasound-assisted cloud point extraction (UA-CPE) using the mixture of non-ionic surfactant alkylphenol ethoxylate NP-7 and alkylphenol ethoxylate NP-9 for the preconcentration of trace amounts of lead (Pb) and cadmium (Cd) in water samples prior to determination by FAAS has been developed. In this method, Pb and Cd react with ammonium pyrrolidinedithiocarbamate (APDC), yielding hydrophobic complexes, which then are extracted into the surfactant-rich phase. Compared with the traditional CPE, faster phase separation and higher recovery were obtained using the ultrasound-assisted process and a series of non-ionic nonyl phenol ethoxylate surfactants in the present UA-CPE. Variable parameters affecting the CPE procedure were evaluated and optimized. Under the optimized conditions, the calibration graph was linear in the range of 10-500 μg L−1 for Pb and Cd. The detection limits were 0.5 μg L−1 and 0.28 μg L−1 with relative standard deviations of 2.6% and 3.4% for Pb and Cd, respectively. The enrichment factors were 57 and 63 for Pb and Cd, respectively, for 10 mL of preconcentrated solution. The method was successfully applied to the determination of Pb and Cd in water samples.
    No preview · Article · May 2014 · Analytical methods
  • Zonghao Li · Jiaxi Chen · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A supramolecular solvent made up of reverse micelles of nonanoic acid, dispersed in a continuous phase of tetrahydrofuran (THF) and water, is proposed for the simple, rapid and efficient microextraction of copper (Cu) and lead (Pb) in water samples prior to flame atomic absorption spectrometry determination. A new Schiff base was synthesized and used as the chelating agent in this study. Some important extraction parameters such as the pH, Schiff base concentration, the composition and volume of the supramolecular solvent and vortex time are evaluated, obtaining the most favorable results. Under the optimized conditions, the calibration curves were linear in the range of 10-800 μg L−1 for Cu and 10-500 μg L−1 for Pb, respectively. The limits of detection (LOD) were 0.29 μg L−1 and 0.45 μg L−1, with the enrichment factors of 27 and 22 for Cu and Pb, respectively. Recoveries of Cu and Pb spiked in water samples were in the range of 91.2-102.1%. The results show that the proposed method is suitable for the determination of Cu and Pb in water samples.
    No preview · Article · Apr 2014 · Analytical methods
  • Qinghai Xia · Yaling Yang · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: The present work describes a simple and rapid extraction approach based on vortex-assisted acid-induced anionic surfactant sodium dodecyl sulfate-mediated extraction (vortex-assisted acid-induced cloud point extraction) prior to spectrofluorometry for the determination of four fluoroquinolones, including norfloxacin, ciprofloxacin, sarafloxacin, and gatifloxacin, in water samples (hospital wastewater, river water, lake water, and water from the inlet of a wastewater treatment plant). Sodium dodecyl sulfate and concentrated hydrochloric acid (12 mol/L) were used as extractants. The four fluoroquinolones were concentrated in the surfactant-rich phase after phase separation and were determined by a spectrofluorophotometer. Some parameters affecting the extraction efficiency, such as the type and amount of surfactant, the amount of acid, vortex treatment, and centrifugation, were optimized systematically. Under the optimized conditions, the proposed method showed good analytical features with linearity for all analytes in a wide range of 0.045–0.90 µg/mL and coefficients of determination no less than 0.9901. The limits of detection (S/N = 3) were 0.007, 0.010, 0.009, and 0.013 µg/mL for norfloxacin, ciprofloxacin, sarafloxacin, and gatifloxacin, respectively; good precisions expressed as the relative standard deviations were in the range of 0.9–3.7% (n = 6); and average recoveries at three spiking levels ranged from 83.0% to 96.7%. The results of the proposed method are comparable to those obtained from the high-performance liquid chromatography method (t-test, p = 0.05) and are reliable for determination of fluoroquinolones in environmental water samples.
    No preview · Article · Mar 2014 · Spectroscopy Letters
  • Zhigang Tai · Yingtang Li · Mousheng Liu · Xujia Hu · Yaling Yang · Benkui Qin
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper describes a sensitive and simple method for the detection of bisphenol A (BPA) and bisphenol AF (BPAF) in vinegar samples using two-component mixed ionic liquid dispersive liquid-liquid microextraction coupled with high performance liquid chromatography. In this work, BPA and BPAF were used as the target analytes, and two-component mixed ionic liquid included 1-butyl-3-methylimidazolium hexafluorophosphate ([C4Mim]PF6) and 1-hexyl-3-methyl-imidazolium hexafluorophosphate ([C6Mim]PF6) was used as the extraction solvent for the first time here. Parameters affecting the extraction efficiency were investigated. Under optimum conditions, better linear relation were discovered in the scope of 1.0-100 μg/L for BPA and 2.0-150 μg/L for BPAF, respectively. Detection limits of this method based on the signal-noise ratio (SNR=3) ranged from 0.15 to 0.38 μg/L. The efficiencies of proposed method have also been demonstrated with spiked real vinegar samples. The result show this method/procedure to be a more efficient approach for the determination of BPA and BPAF in real vinegar, presenting average recovery rate of 89.3-112 % and precision values of 0.9-13.5% (RSDs, n = 6). In comparison with traditional solid phase extraction procedures this method results in lower solvent consumption, low pollution levels, and faster sample preparation.
    No preview · Article · Feb 2014 · Journal- Chemical Society of Pakistan
  • Hui Qin · Xiaoyan Qiu · Jiao Zhao · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: Glucocorticoids contamination has become a big environmental issue in China and other developing countries, due to increasing needs in medical prescription and farming. However, no highly sensitive and precise methods have been reported to quantify glucocorticoids so far. In the past several years, supramolecular solvent-based vortex-mixed microextraction (SS-BVMME) has been shown to be effective. However, the mechanism of SS-BVMME is still unknown. In this report, a novel method has been proposed for rapid quantification of trace amount of glucocorticoids, beclomethasone dipropionate (BD), hydrocortisone butyrate (HB) and nandrolone phenylpropionate (NPP) in water samples from the Green Lake. This method is simple, safe and cost effective. It contains two steps: supramolecular solvent-based vortex-mixed microextraction (SS-BVMME) technique and high performance liquid chromatography (HPLC) analysis. First, ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and n-butanol were mixed to form the supramolecular solvent. After mixing the supramolecular solvent with an aqueous sample to test, a homogenous mixture was formed immediately. BD, HB and NPP were then extracted based on their binding interactions, particularly hydrogen bond formed between their hydroxyl group and the supramolecular solvent. The overall process of sample preparation took only 20min and more than 5 samples could be simultaneously prepared. The minimum detectable concentrations of samples in this method were 0.09925, 0.5429 and 2.428ngmL(-1) for BD, HB and NPP, respectively. Product recoveries ranged from 88% to 103% with relative standard deviations from 0.6% to 4%. For the first time, we report that hydrogen bond plays a key role in SS-BVMME. We also improve the sensitivity significantly to quantify glucocorticoids, which may greatly benefit environmental safety management in China.
    No preview · Article · Aug 2013 · Journal of Chromatography A
  • Qinghai Xia · Yang Jiao · Wei Xiong · Yaling Yang · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: In this work, a 4-chloro-7-nitrobenzodioxazole (NBD-Cl) derivatization coupled with the ultrasound-assisted cloud point extraction (UACPE) method prior to high-performance liquid chromatography with fluorescence detection (HPLC-FLD) analysis was developed for the determination of four widely used fluoroquinolones (FQs) including norfloxacin (NOR), ciprofloxacin (CIP), sarafloxacin (SAR), and gatifloxacin (GAT) in eggs. The derivatives of FQs with NBD-Cl were extracted into the Triton X-114 surfactant-rich phase, which was analyzed by reversed-phase HPLC-FLD. Ultrasound was applied to accelerate the phase separation in extraction and enhance the extraction efficiency of target analytes. Variable parameters affecting the derivatization and UACPE procedure were systematically evaluated and optimized. Under the optimum conditions, four FQs were successfully separated within 30 min through an Agilent TC-C18 column. Good recoveries of 86.2–103.5 %, which were calculated using a range of spiked samples at three concentrations, were obtained by UACPE. The calibration graphs were linear over the range of 1.2–73.0 μg kg−1 for four FQs with correlation coefficients (R) no less than 0.9957. The limits of detection were 0.2, 0.5, 0.3, and 0.4 μg kg−1 for NOR, CIP, SAR, and GAT, respectively. The precisions indicated by relative standard deviations ranged from 0.6 to 4.3 % for both intraday and interday analysis. The proposed method proved to be a selective, sensitive, and eco-friendly approach which was successfully applied to analyze FQs in eggs at the local farmers market, and none of the target analytes were detected in these samples.
    No preview · Article · May 2013 · Food Analytical Methods
  • Qinghai Xia · Yaling Yang · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: A simple and sensitive spectrofluorimetric method was developed for the determination of four fluoroquinolone antibacterials namely norfloxacin (NOR), ofloxacin (OFL), ciprofloxacin (CIP) and gatifloxacin (GAT) in honey through charge transfer (CT) complex formation with 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and then the inclusion complexes of FQs-DDQ with β-cyclodextrin (β-CD) were formed, which resulted in drastic fluorescence enhancement. The effect of several parameters including the concentration of reactants, reaction temperature, time and ultrasonic treatment on the efficiency of the proposed method involving CT reaction and inclusion interaction was systematically investigated. Under the optimum conditions, the limits of detection (LODs) for four FQs in honey varied from 11.6 to 15.4 μg/kg (signal-to-noise ratio (S/N) = 3). The intra- and interday relative standard deviations (RSDs) were 1.6-4.0 % (n = 5) for four FQs. The calibration graph was linear from 42.8 to 1346.8 μg/kg with correlation coefficients not less than 0.9905. The recoveries of four FQs at three different spiked concentrations in honey samples ranged from 80.9 % to 92.8 %. The results indicated that the method was successfully applied for analyzing FQs in honey.
    No preview · Article · Mar 2013 · Journal of Fluorescence
  • Miao Chen · Xujia Hu · Zhigang Tai · Hui Qin · Huinan Tang · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A cloud-point extraction (CPE) method using Tergitol TMN-6 (TMN-6) non-ionic surfactant was developed for the extraction and preconcentration of propyl gallate (PG), tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in edible oils. The optimum conditions of CPE were 1.5 % (v/v) Tergitol TMN-6, 1 % (w/v) NaCl, ultrasound-assist 15 min at 49 KHz, 20 min equilibrated at 45 °C, and centrifugation for 10 min at 3,000 rpm. The surfactant-rich phase was then analyzed by reversed-phase high-performance liquid chromatography (HPLC) with ultraviolet detection at 280 nm, under gradient separation, using methanol and 1.5 % (v/v) acetic acid. Under the study conditions, four synthetic phenolic antioxidants (SPAs) were successfully separated within 24 min. Limits of detection in the studied edible oils were in the range of 1.6 to 9.0 ng mL−1. The high recoveries of the spiked edible oils were obtained in the range 90–98 %. The CPE method has been shown to be a potentially useful methodology for the preconcentration of the target analytes, with a preconcentration factor of 25. This method was compared with cloud point extraction (using Triton X-114) and liquid–liquid extraction (using methanol).
    No preview · Article · Feb 2013 · Food Analytical Methods
  • Zonghao Li · Gong Yu · Jun Song · Qi Wang · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A new, simple and rapid method based on dispersive liquid-liquid microextraction (DLLME) was developed for extracting and preconcentrating copper (Cu), nickel (Ni), lead (Pb) and cadmium (Cd) in water samples prior to flame atomic absorption spectrometry (FAAS) analysis. 1-(2-thiazolylazo)-naphthol (TAN) was used as chelating reagents, and non-ionic surfactant Triton X-114 and CCl(4) as disperser solvent and extraction solvent, respectively. Some influential factors relevant to DLLME, such as the concentration of TAN, type and volume of disperser and extraction solvent, pH and ultrasound time, were optimized. Under the optimal conditions, the calibration curve was linear in the range of 10-800 μg L(-1) for Cu and Ni, 10-500 μg L(-1) for Pb, and 10-1,000 μg L(-1) for Cd, respectively. The limits of detection for the four metal ions were below 0.5 μg L(-1), with the enhancement factors of 105, 66, 28 and 106 for Cu, Ni, Pb and Cd, respectively. The relative standard deviations (RSD, n = 6) were 2.6-4.1%. The proposed method was applied to determination of Cu, Ni, Pb and Cd in water samples and satisfactory relative recoveries (93.0-101.2%) were achieved.
    No preview · Article · Nov 2012 · Water Science & Technology
  • Qinghai Xia · Yaling Yang · Mousheng Liu
    [Show abstract] [Hide abstract]
    ABSTRACT: An aluminium sensitized spectrofluorimetric method coupled with salting-out assisted liquid-liquid ultrasonic extraction for the determination of four widely used fluoroquinolones (FQs) namely norfloxacin (NOR), ofloxacin (OFL), ciprofloxacin (CIP) and gatifloxacin (GAT) in bovine raw milk was described. The analytical procedure involves the fluorescence sensitization of aluminium (Al(3+)) by complexation with FQs, salting-out assisted liquid-liquid ultrasonic extraction (SALLUE), followed by spectrofluorometry. The influence of several parameters on the extraction (the salt species, the amount of salt, pH, temperature and phase volume ratio) was investigated. Under optimized experimental conditions, the detection limits of the method in milk varied from 0.009μg/mL for NOR to 0.016μg/mL for GAT (signal-to-noise ratio (S/N)=3). The relative standard deviations (RSD) values were found to be relatively low (0.54-2.48% for four compounds). The calibration graph was linear from 0.015 to 2.25μg/mL with coefficient of determinations not less than 0.9974. The methodology developed was applied to the determination of FQs in bovine raw milk samples. The main advantage of this method is simple, accurate and green. The method showed promising applications for analyzing polar analytes especially polar drugs in various sample matrices.
    No preview · Article · May 2012 · Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy
  • Source
    Yan Zou · Yanhua Li · Hua Jin · Deqing Zou · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: Desenvolveu-se um procedimento de microextração por emulsificação assistida por ultrassom e aperfeiçoada por surfactante (UASEME) combinado com cromatografia líquida de alta eficiência com detector de arranjo de diodos para a determinação de 17b-estradiol (βE2), estrona (E1) e dietilestilbestrol (DES) em água. Ultrassom foi aplicado para auxiliar a emulsificação e Triton X-100 foi usado como dispersor e emulsificante. Tetracloreto de carbono foi usado como solvente extrator. Empregando otimização global, o procedimento foi caracterizado por um intervalo linear aceitável de 10 a 1000 ng mL-1 para βE2, E1 e DES (r > 0,997), exatidão e precisão validadas (RSD 0,85-1,28% (n = 5)) e alta sensibilidade com limites de detecção de 0,200, 0,100 e 0,125 ng mL-1 para βE2, E1 e DES, respectivamente. O procedimento foi aplicado para a análise de amostras típicas de água, com fatores de enriquecimento de 85,29, 173,45 e 97,05 para βE2, E1 e DES, respectivamente, e boas recuperações (≥ 89,82%). De maneira geral, o procedimento desenvolvido foi simples e confiável, com potencial de aplicação em larga escala para análises da água.
    Preview · Article · Apr 2012 · Journal of the Brazilian Chemical Society
  • Miao Chen · Zhigang Tai · Xujia Hu · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A spectrofluorimetric method is presented for the determination of 2 synthetic phenolic antioxidants (SPAs), butylated hydroxyanisole (BHA), and propyl gallate (PG) in foodstuffs. The proposed method is based on the derivatization of SPAs with 4-chloro-7-nitrobenzofurazan (NBD-Cl) in phosphate buffer of pH 9.0 to yield a highly fluorescent brown product. The optimum experimental conditions have been studied carefully. Linear calibration curves were obtained over the concentration range of 0.20 to 40 μg mL−1 for BHA, and 0.80 to 50 μg mL−1 for PG, using NBD-Cl reagent. The detection limits were 18 ng mL−1 for BHA, 55 ng mL−1 for PG. Intra-day and inter-day relative standard deviations at 3 different concentrations were determined. The high recovery values indicate the accuracy of the proposed methods, and low relative standard deviation values indicate good precision. The results presented in this report show that the applied spectrofluorimetric method is acceptable for the determination of the 2 SPAs in the foodstuffs. Other SPAs, tertiary butyl hydroquinone and butylated hydroxytoluene in foodstuffs do not interfere with the proposed method. Practical Applications: In this spectrofluorimetric method, NBD-Cl as a derivation agent is used to detect synthetic phenolic antioxidants. The method specificity has been greatly improved; there was no interference from other commonly used phenolic substances.
    No preview · Article · Mar 2012 · Journal of Food Science
  • Yan Zou · Yanhua Li · Hua Jin · Huinan Tang · Deqing Zou · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: A novel and efficient analytical methodology is proposed for extracting and preconcentrating three kinds of estrogens (17β-estradiol (βE2), estrone (E1), and diethylstilbestrol (DES)) in human urine prior to high-performance liquid chromatography (HPLC) analysis. It is based on the induction of micellar organized medium by using a nonionic surfactant (Tergitol TMN-6) to extract the target estrogens. Ultrasound was applied to enhance the extraction efficiency. Parameters affecting the extraction of target analytes including the concentration of surfactant, temperature, extraction time, sample pH, ionic strength, and centrifuging time were investigated. Under the optimum conditions, the linear range of βE2, E1, and DES was from 5.0 to 1000 ng/ml. All correlation coefficients of the calibration curves were higher than 0.997. The relative standard deviations (RSD, n=5) were 2.36-5.27% and the limits of detection (LOD) were 0.1, 0.2, and 0.1 ng/ml for βE2, E1, and DES in human urine, respectively. The results indicated that the method was successfully applied for analyzing βE2, E1, and DES in human urine.
    No preview · Article · Feb 2012 · Analytical Biochemistry
  • Yan Zou · Weidong Geng · Mousheng Liu · Yaling Yang
    [Show abstract] [Hide abstract]
    ABSTRACT: In presence of the HOAc-NaOAc buffer solution and heating condition, leucomalachite green (LMG) can reacts with I3- to form an ionassociation complex. It made a significant enhancement of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS). The increments of scattering intensity (DI) were directly proportional to the concentration of leucomalachite green in a certain range. The detection limits were 1.2 ng mL-1 for resonance Rayleigh scattering method, 1.5 ng mL-1 for second-order scattering method and 1.5 ng mL-1 for frequency doubling scattering method, respectively. This result indicates that these methods exhibited high sensitivities. And they were simple and feasible. Three new highly sensitive and simple methods of determination leucomalachite green have been developed. With the reducing action of potassium borohydride, over 85 % of malachite green (MG) can be converted to leucomalachite green. So these can be applied to determine the malachite green in aquatic products.
    No preview · Article · Dec 2011 · Asian Journal of Chemistry