Zilin Chen

Hubei University of Chinese Medicine, Shih-yen, Hubei, China

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Publications (87)196.13 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: A gas chromatographic–mass spectrometric method with monolithic material sorptive extraction (MMSE) pretreatment was developed to determine the breath gas composition in lung cancer patients. MonoTrap silica monolithic and hybrid adsorbent was selected as the extraction medium during MMSE, given its strong capacity to extract volatile organic compounds (VOC) from exhaled gas. Under the appropriate conditions, high extraction efficiency was achieved. Using the selected ion-monitoring mode, the limit of detection (signal-to-noise ratio 3) for the benzene series was 0.012–2.172 ng L−1. The limit of quantitation (signal-to-noise ratio, 10) was 0.042–7.24 ng L−1. The linearity range of the method was 4–400 ng L−1. Average recovery of the benzene series at lower concentrations was 65–74% (20 ng L−1). The relative standard deviation of benzene series contents determined within the linear range of detection was <10% of the mean level determined. Our proposed method is simple, rapid and sensitive, and can be competently applied to determine the breath gas composition of lung cancer patients. Copyright © 2014 John Wiley & Sons, Ltd.
    Biomedical Chromatography 11/2014; · 1.95 Impact Factor
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    ABSTRACT: In this work, we interestingly happened to observe the adsorption of stainless steel sample loop of HPLC. The adsorptive behaviors of the stainless steel loop toward different kinds of compounds were studied, including polycyclic aromatic hydrocarbons (PAHs), halogeno benzenes, aniline derivatives, benzoic acid derivatives, phenols, benzoic acid ethyl ester, benzaldehyde, 1-phenyl-ethanone and phenethyl alcohol. The adsorptive mechanism was probably related to hydrophobic interaction, electron-rich element-metal interaction and hydrogen bond. Universal adsorption of stainless steels was also testified. Inspired by its strong adsorptive capability, bare stainless steel loop was developed as a modification-free in-tube device for solid-phase microextraction (SPME), which served as both the substrate and sorbent and possessed ultra-high strength and stability. Great extraction efficiency toward PAHs was obtained by stainless steel loop without any modification, with enrichment factors of 651-834. By connecting the stainless steel loop onto a six-port valve, an online SPME-HPLC system was set up and an SPME-HPLC method has been validated for determination of PAHs. The method has exceptionally low limits of detection of 0.2-2pg/mL, which is significantly lower than that of reported methods with different kinds of sorbents. Wide linear range (0.5-500 and 2-1000pg/mL), good linearity (R(2)≥0.9987) and good reproducibility (RSD≤2.9%) were also obtained. The proposed method has been applied to determine PAHs in environmental samples. Good recoveries were obtained, ranging from 88.5% to 93.8%.
    Journal of Chromatography A 09/2014; · 4.61 Impact Factor
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    Haiyan Zhao, Zilin Chen
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    ABSTRACT: A transverse diffusion mediated capillary microanalysis method has been developed for screening of neuraminidase inhibitors from traditional Chinese medicine. The enzyme, substrate and inhibitors were sequentially injected, mixed efficiently by transverse diffusion of laminar flow profiles, then incubated and separated in the same capillary. To enhance the mixing efficiency of reactants, running buffer was injected by alternately applying þ5 kPa and À5 kPa at the capillary inlet and the procedure was repeated three times. The capillary electrophoresis (CE) separation conditions and reactants mixing conditions were optimized. Dual-wavelength detection was employed to eliminate the interference with natural compounds. The method has been applied to determine the kinetics constant of neuraminidase and screen 12 compounds from traditional Chinese medicine. Four compounds have been found to be positive for enzyme inhibition. The results are in good agreement with those reported in the literature. The method realized the mixing of substrate and enzyme with identical electrophoretic mobility. This novel CE method was simple, rapid, economic, and fully automated. Therefore, it was appropriate for neuraminidase inhibitors screening and could be extended to other high-throughput screening of active components from traditional Chinese medicine.
    Biomicrofluidics 08/2014; 8. · 3.39 Impact Factor
  • Wenpeng Zhang, Wei Zhou, Zilin Chen
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    ABSTRACT: Determination of bioactive compounds in traditional Chinese medicines and biological samples is usually interfered by co-existing components in matrices. In this work, we prepared novel multilayer functional graphene/polydopamine-modified polytetrafluoroethylene microtube for selective solid-phase microextraction of three bioactive compounds in Fructus Psoraleae. Functional graphene/polydopamine-modified polytetrafluoroethylene microtube showed good extraction efficiency towards bavachin, isobavachalcone and bavachinin; enrichment from 357- to 737-fold was obtained for these compounds. For qualitative analysis, an online solid-phase microextraction with high-performance liquid chromatography method was developed, which showed low limits of detection of 0.02 ng/mL by using UV detection, which is significantly more sensitive than previously reported methods. The proposed method has been used to determine bavachin, isobavachalcone and bavachinin in Fructus Psoraleae, the contents of three compounds were quantified to be 64.0, 324.0 and 384.5 (μg/g); recoveries were 93.4–101.1%. The proposed method has also been applied to determine bavachin, isobavachalcone and bavachinin in rat plasma samples after oral administration of Fructus Psoraleae.This article is protected by copyright. All rights reserved
    Journal of Separation Science 08/2014; · 2.59 Impact Factor
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    ABSTRACT: Stainless steel wire is a good substrate for jacket-free stir bar sorptive extraction (SBSE). In this work, we present the first example of chemical modification of graphene on stainless steel wire (SSW) for SBSE. Bio-inspired polydopamine was firstly modified on the SSW covalently; then graphene oxide was introduced and reacted with amino groups of polydopamine layer. The modification of polydopamine and graphene can be repeated by a layer-by-layer strategy, resulting in control of the thickness of graphene layer and increase of extraction capability. The prepared covalently immobilized graphene-stainless steel wire (G-SSW) exhibited good stability under stirring, ultrasonication and treatment with commonly used organic solvents, basic and acidic solutions. Application as stir bar for SBSE, G-SSW was found to possess good extraction efficiency towards pollutant polyaromatic hydrocarbons (PAHs), with enrichment factors from 10086 to 16896. After optimization of conditions, G-SSW based SBSE was coupled HPLC for determination of PAHs in environmental and food samples. The quantitative method has low limits of detection of 0.2-50pg/mL, which is better than some reported SBSE-HPLC methods. The method shows wide linear range (200-5000, 10-1000 and 1-1000pg/mL), good linearity (r≥0.9950) and good reproducibility (RSD≤4.97%). The method has been applied to soil and food samples, with good selectivity and good recoveries ranging from 88.5-113.6%.
    Journal of chromatography. A. 05/2014;
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    ABSTRACT: In this work, we fabricated a novel graphene-based capillary column for open tubular capillary electrochromatography (OT-CEC) by a layer-by-layer strategy. To immobilize graphene onto the inner surface of silica capillary, a bio-inspired method was first used to functionalize the capillary surface with a layer of polydopamine (PDA). Graphene oxide (GO) was then introduced and can covalently react with polydopamine, realizing immobilization of graphene as a result. To enhance the modification efficiency of polydopamine, a conductive polymer, polyaniline (PANI) was introduced to be a sub-layer; polydopamine was then introduced following with GO, to generate a multilayer GO-PDA-PANI@capillary. Interestingly, separation efficiency of the graphene-based capillary was enhanced significantly by using conductive PANI as a sub-layer. The morphology of different layers modified on the capillary column was characterized by scanning electron microscopy (SEM). The electroosmotic flow (EOF) characteristics of capillaries modified with different layers were also investigated by varying the pH value of mobile phase. GO-PDA-PANI@capillary showed good separation efficiency towards alkylbenzenes by OT-CEC mode, with theoretic plate numbers up to 133918 for benzene. The separation was found to follow a reversed-phase chromatographic retention mechanism. Repeatability of the GO-PDA-PANI@capillary was studied, with relative standard deviations for intra-day and inter-day runs less than 2.89%, and column-to-column runs less than 6.17%. The separation performance of GO-PDA-PANI@capillary was also compared with that of the reported graphene modified capillary.
    Journal of Chromatography A 04/2014; · 4.61 Impact Factor
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    Haiyan Zhao, Zilin Chen
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    ABSTRACT: A simple and effective neuraminidase-immobilized capillary microreactor was fabricated by glutaraldehyde cross-linking technology for screening the neuraminidase inhibitors from traditional Chinese medicines. The substrate and product were separated by CE in short-end injection mode within 2min. Dual-wavelength ultraviolet detection was employed to eliminate the interference from the screened compounds. The parameters relating to the separation efficiency and the activity of immobilized neuraminidase were systematically evaluated. The activity of the immobilized neuraminidase remained 90% after 30 days storage at 4°C. The immobilized NA microreactor could be continuously used for more than 200 runs. The Michaelis-Menten constant of neuraminidase was determined by the microreactor as 136.6±10.8μM. In addition, six in eighteen natural products were found as potent inhibitors and the inhibition potentials were ranked in the following order: bavachinin>bavachin>baicalein>baicalin>chrysin and vitexin. The half-maximal inhibitory concentrations were 59.52±4.12, 65.28±1.07, 44.79±1.21 and 31.62±2.04 for baicalein, baicalin, bavachin and bavachinin, respectively. The results demonstrated that the neuraminidase-immobilized capillary microreactor was a very effective tool for screening neuraminidase inhibitors from traditional Chinese medicines.
    Journal of Chromatography A 03/2014; · 4.61 Impact Factor
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    Liping Ren, Haiyan Zhao, Zilin Chen
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    ABSTRACT: A fast and simple liquid chromatography-mass spectrometry method for the determination of lycorine in mice plasma and tissues was developed and well used in the pharmacokinetic and tissue distribution study of lycorine after tail vein injection and intraperitoneal administration. Biological samples were processed with ethyl acetate by liquid-liquid extraction, and evodiamine was used as the internal standard. Chromatographic separation was performed on an Amethyst C18 column (4.6×150mm) with a mobile phase consisting of methanol and water. Quantification was performed by selected ion monitoring with m/z 288 [M+H](+) for lycorine and m/z 304 [M+H](+) for the internal standard. Good linearity was observed over the concentration ranges. Limits of quantification were low up to 10.0ng/mL in plasma samples, 9.0ng/g for lung, 12.0ng/g for heart, 18.0ng/g for spleen and 6.5ng/g for other tested tissues. The intraday accuracy and precision in plasma and tissues ranged from -7.4% to 9.1%. Recoveries in plasma and tissue were more than 80%. The method was rapid, accurate and fully validated. It was successfully applied to the investigation of the pharmacokinetics and tissue distribution of lycorine in mice.
    Talanta 02/2014; 119C:401-406. · 3.50 Impact Factor
  • Xiaoli Mou, Wenpeng Zhang, Zilin Chen
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    ABSTRACT: Selective extraction of bioactive compounds in natural products and traditional medicines is difficult but necessary for drug analysis and new drug development. In this study, baicalin-imprinted polymer particles were prepared for selective recognition and extraction of baicalin from herbs and traditional Chinese medicines. The molecularly imprinted polymer (MIP) was synthesized by co-polymerization of 4-vinylpridine and ethylene glycol dimethacrylate in the presence of baicalin with a ratio of 8 : 40 : 1, where N,N-dimethyl formamide/acetonitrile served as porogen. The prepared MIP particles showed good selectivity by comparing with non-imprinted polymer and possessed an imprinted factor of 2.17; selectivity to other molecules was also tested by extracting an analogue, naringin. The performances of the MIP particles were systematically investigated, including adsorption kinetics, isotherm experiment, and Scatchard analysis. The imprinted particles were also applied to extract baicalin from natural herb Plantago asiatica L, and traditional Chinese medicine Longdanxiegan bolus. The results showed that baicalin in these complex matrixes could be selectively extracted and well isolated with other components. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1873–1878, 2013
    Journal of Applied Polymer Science 11/2013; 130(3). · 1.40 Impact Factor
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    ABSTRACT: A novel capillary with hydroxyapatite (HAP) as the stationary phase was prepared for open-tubular capillary electrochromatography (OT-CEC). To immobilize HAP, a mussel-inspired polydopamine method was utilized to modify the capillary firstly, generating a polydopamine layer; and then a layer of HAP would be formed on the polydopamine layer by a biomineralization process, to produce a HAP-modified capillary (HAP@capillary). Scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS) provided evidence of nanostructured HAP grown on the surface of the capillary wall. The electroosmotic flow (EOF) characteristic of the HAP@capillary was investigated by varying the percentage of acetonitrile and pH value of the buffer with thiourea as a marker, and a pH-dependent EOF from anode to cathode was observed. The HAP@capillary exhibits high column efficiency for methylbenzene, up to 151 138 plates per meter. Different kinds of compounds including alkylbenzenes, phenols and amines have been successfully separated by the HAP@capillary in CEC mode. The HAP@capillary also possessed good separation ability in capillary liquid chromatography (CLC) mode because of the relatively large ratio of HAP in the capillary; however, the separation efficiency was not as good as that in CEC mode. The reproducibilities of the HAP@capillary were evaluated, and the relative standard deviations were found to be lower than 5%.
    The Analyst 11/2013; · 4.23 Impact Factor
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    ABSTRACT: Sarcosine, a potential biomarker of prostate cancer, has drawn great attention in recent years. However, controversial research keeps arising about its role as a biomarker that might come from the two isomers (α-alanine and β-alanine) of sarcosine due to their same molecular weight and similar properties, which could interfere with the accurate detection of sarcosine. In this study, a simple and sensitive method was developed for the detection of sarcosine and the two isomers by LC with ion-trap MS through a novel derivatization reagent N,N'-dicyclohexylcarbodiimide. N,N'-Dicyclohexylcarbodiimide is usually considered as a condensation reagent, however, it was directly used as a derivatization reagent through a rearrangement side reaction in this study. The proposed method not only improved the chromatographic retention behavior of sarcosine and its two isomers, which was a benefit to their separation, but also dramatically enhanced the detection sensitivity of sarcosine, which was more favorable for real sample analysis. The factors affecting the productivity of the derivatization reaction, such as reaction time and amount of derivatization reagent, were systematically optimized. The method shows good linearity (R(2) > 0.99), sensitivity with LODs of sarcosine as low as 1 ng/mL, and repeatability with the RSD < 6.07%. The developed method was applied to the analysis of urine.
    Journal of Separation Science 11/2013; · 2.59 Impact Factor
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    ABSTRACT: A novel method for analysis of three active components curcumin, demethoxycurcumin and bisdemethoxycurcumin in Curcuma longa L. was developed by HPLC coupled with electrochemical detection. Three curcuminoids were well separated on C18 column and detected with high sensitivity. A mobile phase containing acetonitrile and 10 mM Na2HPO4 - H3PO4 (pH 5.0) (50:50, v/v) was used. Good linearity was obtained in the range of 0.208–41.6, 0.197–39.4, 0.227–114 μM for curcumin, demethoxycurcumin and bisdemethoxycurcumin. The limit of detection reached up to 10−8 M, which was lower than that by UV detection. The relative standard deviations (RSDs) were ranged from 1.06% to 1.88% for intra-day precision and from 4.30% to 5.79% for inter-day precision, respectively. The proposed method has been applied in real herb sample and recoveries ranged from 86.3% to 111% were obtained.
    Journal of Pharmaceutical Analysis. 11/2013;
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    ABSTRACT: Catharanthus roseus is an important dicotyledonous medicinal plant that produces anticancer compounds. The active alkaloids vinblastine, vindoline, ajmalicine, catharanthine, and vinleurosine were identified by direct-injection ion trap-mass spectrometry (IT-MS) for collecting MS(1-2) spectra. The determinations of five alkaloids were accomplished by liquid chromatography (LC) with UV and MS detections. The analytes provided good signals corresponding to the protonated molecular ions [M+H](+) and product ions. The precursor ions and product ions for quantification of vinblastine, vindoline, ajmalicine, catharanthine, and vinleurosine were m/z 825→807, 457→397, 353→144, 337→144 and 809→748 by LC-IT-MS, respectively. Two methods were used to evaluate a number of validation characteristics (repeatability, LOD, calibration range, and recovery). MS provided a high selectivity and sensitivity for determination of five alkaloids in positive mode. After optimisation of the methods, separation, identification and quantification of the five components in C. roseus were comprehensively accomplished by HPLC with UV and MS detection.
    Food Chemistry 08/2013; 139(1-4):845-52. · 3.33 Impact Factor
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    ABSTRACT: Graphene is a new kind of two-dimensional carbon nanomaterial with excellent properties and is promising for solid-phase microextraction (SPME). Plastic micro-tubes such as polytetrafluoroethylene (PTFE) and poly(ether ether ketone) are ideal substrates for in-tube SPME. However, immobilization of graphene layers onto these materials is still a problem due to their nature of chemical resistance. In order to solve the problem, we proposed a novel method based on universal mussel inspired polydopamine (PD) and layer-by-layer assembly of graphene in this work. To make a graphene assembly layer inside PTFE, the strategy includes two major steps. First, a universal mussel inspired polydopamine layer is made on the PTFE surface by non-covalent interaction. Second, multilayer graphene is assembled on PD layer by covalent interaction. By repeating above two steps, a reduced graphene oxide (RGO)-modified PTFE tube with controllable number of layer can be obtained. The morphology of multilayer structure of graphene has been confirmed by scanning electronic microscopy (SEM). The formation of covalent layer has also been characterized by FT-IR and X-ray photoelectron spectroscopy (XPS). It is very interesting that (RGO-PD)3-PTFE shows exceptional efficiency for SPME. Enrichment folds from 1082 to 2331 were achieved for six polyaromatic hydrocarbons (PAHs). An online SPME-HPLC-fluorescent detection method has been developed on the basis of (RGO-PD)3-PTFE. For qualitative analysis of PAHs, the method has low limits of detection of 0.05-0.1 pg/mL, which is significantly lower (up to 1000 times) than that reported in literatures. The method shows wide linear range (0.3-200 pg/mL), good linearity (R2 ≥ 0.9968) and good reproducibility (RSD < 3.4%). The method has been applied to determine PAHs in environmental samples. Good recoveries were obtained, ranging from 85.1 to 96.7%.
    Analytical Chemistry 06/2013; · 5.82 Impact Factor
  • Wen Ma, Shuai Fu, Yuki Hashi, Zilin Chen
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    ABSTRACT: A GC/MS method with monolithic material sorptive extraction (MMSE) pretreatment was developed to determine contents of the enantiomers of jasmonic acid and methyl jasmonate in flowers. To optimize MMSE extraction, several MMSE parameters were investigated, including extraction temperature, extraction time, and extraction solvent. Under the optimal conditions, extraction efficiency was good. Using the selected-ion monitoring mode, the limit of detection (LOD, S/N = 3) for methyl jasmonates was 0.257 ng/mL. The limit of quantitation (LOQ, S/N = 10) was 0.856 ng/mL. The linearity range was 1-100 ng/mL. The average recovery of methyl jasmonate at lower concentration was 116.8% (2 ng/mL). The relative standard deviation of methyl jasmonate contents determined within the linear range of detection was less than or equal to 15% of the mean determined level. The proposed method is rapid, sensitive, and competently applied to the determination of jasmonic acid and methyl jasmonate enantiomers in flowers.
    Journal of Agricultural and Food Chemistry 06/2013; · 3.11 Impact Factor
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    ABSTRACT: As a transcellular messenger molecule, nitric oxide (NO) is involved in many physiological and pathological processes. The accurate quantitative detection of NO in vivo is particularly important. In this work, a novel electrochemical NO sensor was fabricated via electro-polymerization of ethylenediamine (EDA) on multi-walled carbon nanotubes (MWNTs) film. The sensor combined the porous structure and good conductivity of MWNTs with the good electro-catalytic ability of p-EDA film. For the detection of NO, it has a linear range from 95nM to 11μM and the limit of detection reaches 95nM with excellent reproducibility. So it was successfully applied to monitor NO release from rat liver sample for investigating the inhibition or promotion effect of drugs including oleanolic acid (OA), baicalin and Nω-nitro-l-arginine methyl ester (l-NAME) on nitric oxide synthase (NOS). The results showed that OA could promote NO release and the amount of NO increases about 1.9 times, but baicalin and l-NAME could inhibit the release of NO and the amount of NO decreased by two-thirds and 37.5%, respectively.
    Biosensors & Bioelectronics 06/2013; 50C:57-61. · 6.45 Impact Factor
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    Haiyan Zhao, Zilin Chen
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    ABSTRACT: An electrophoretically mediated microanalysis method with partial filling technique was developed for screening aromatase inhibitors in traditional Chinese medicine. The in-capillary enzymatic reaction was performed in 20 mM sodium phosphate buffer (pH 7.4) and sodium phosphate buffer (20 mM, pH 8.0) was used as a background electrolyte. A long plug of coenzyme reduced β-nicotinamide adenine dinucleotide 2'-phosphate hydrate dissolved in the reaction buffer was hydrodynamically injected into a fused silica capillary followed by the injection of reaction buffer, enzyme and substrate solution. The reaction was initiated with a voltage of 5 kV applied to the capillary for 40 s. The voltage was turned off for 20 min to increase the product amount and again turned on at a constant voltage of 20 kV to separate all the components. Direct detection was performed at 260 nm. The enzyme activity was directly assayed by measuring the peak area of the produced β-nicotinamide adenine dinucleotide phosphate and the decreased peak area indicated the aromatase inhibition. Using the Lineweaver-Burk equation, the Michaelis-Menten constant was calculated to be 50 ± 4.5 nM. The method was applied to the screening of aromatase inhibitors from fifteen natural products. Seven compounds were found to have potent aromatase inhibitory activity. This article is protected by copyright. All rights reserved.
    Journal of Separation Science 06/2013; · 2.59 Impact Factor
  • Ying Chen, Zilin Chen
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    ABSTRACT: In the present work, a pre-column fluorescent derivatization reagent, fluorescein-core piperazine (FCP) was prepared for labeling jasmonic acid (JA). Based on the enhanced fluorescence after derivatization, a simple and sensitive method was developed for determination of JA by high performance liquid chromatography with fluorescence detection (HPLC/FD). Several key derivatization conditions were examined. The results indicated that FCP labeled JA could be well separated from FCP in the sample within 13 min on a C18 reversed-phase column using a mobile phase of methanol–water (55:45, v/v) with fluorescence detection at excitation and emission wavelength of 507 nm and 526 nm, respectively. The detection limit obtained was 0.4 nM (signal to noise ratio of 3), which was lower than most of the existing methods. The method is reproducible and yields single peak for JA regardless of isomer. The specificity of the proposed method was confirmed by high-performance liquid chromatography-ion trap mass spectrometry (HPLC/IT-MS). Finally, it has been demonstrated that the proposed HPLC/FD method can be applied to the assay of JA in plant samples.
    Analytical methods 03/2013; 5(7):1733-1738. · 1.86 Impact Factor
  • Ying Chen, Zilin Chen
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    ABSTRACT: Jasmonic acid (JA) conjugates with amino acids (AAs) are a group of plant hormone in the family of jasmonates. The separation of stereoisomers of JA-AA conjugates is a very challenging work since these stereoisomers have similar chromatographic and electrophoretic behavior. Simultaneous separation of ten (±)-JA conjugates with five AAs including l-Tyr (tyrosine), l-leucine, l-Ile (isoleucine), l-valine, and l-phenylalanine and their stereoisomers has been achieved by MEKC with diode array detector in this work. Optimum separation of the analytes was obtained on a 61.5 cm × 75 μm id capillary using a running buffer containing 80 mM SDS and 50 mM phosphates (pH 7.0) at +18 kV applied voltage and capillary temperature of 35°C. Ten stereoisomers of JA conjugates with five AAs are completely separated in 13 min. The RSDs of the migration times and peak areas of the ten stereoisomers were in the range of 0.48-1.03% and 1.03-2.07%, respectively. In the tested concentration range, good linear relationships (correlation coefficients above 99%) between peak areas and concentrations of the analytes were observed. The proposed method has been successfully applied to the analysis of spiked rice floret sample and original reaction solution of (±)-JA-Ile conjugate and (±)-JA-Tyr conjugate. The recoveries ranged from 91.7 to 107.6% for the rice floret sample and 92.9 to 107.2% for the original reaction solution.
    Journal of Separation Science 03/2013; 36(5):892-897. · 2.59 Impact Factor
  • Haiyan Zhao, Zilin Chen
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    ABSTRACT: A sensitive HPLC-ESI-MS method for the simultaneous determination of loureirin A (LA) and loureirin B (LB) in rat plasma and tissues was developed, and the pharmacokinetic and tissue distribution characteristics of LA and LB were investigated after gavage administration. The samples were pretreated by protein precipitation with ethyl acetate and then separated on a Welch Ultimate XB-C18 column with water-acetonitrile (42:58, v/v) containing 0.1% glacial acetic acid as the mobile phase. The analytes were detected with no interference in multiple reaction monitoring (MRM) mode on an electrospray ionization ion trap mass spectrometer. The analytes showed good linearity over a wide concentration range and the lowest limit of quantification (LLOQ) was 5ng/mL for LA and 2ng/mL for LB in matrices. The pharmacokinetic curves of both analytes were best fitted to one-compartment model. It suggested that the analytes absorbed and distributed very quickly in rats. Tissue distribution results showed that the analytes had a wide distribution in tissues and the high levels for LA and LB were observed in liver followed by kidney, lung, spleen, heart and cerebrum. This work provided the pharmacokinetics and tissue distribution characteristics of LA and LB, which would be instructive for their clinical regiment design.
    Fitoterapia 02/2013; · 2.23 Impact Factor

Publication Stats

528 Citations
196.13 Total Impact Points

Institutions

  • 2013
    • Hubei University of Chinese Medicine
      Shih-yen, Hubei, China
  • 2006–2013
    • Wuhan University
      • • School of Pharmaceutical Sciences
      • • Department of Pharmaceutical Analysis and Screening
      • • Department of Chemistry
      Wuhan, Hubei, China
  • 2005–2007
    • University of Notre Dame
      • Department of Chemical and Biomolecular Engineering
      United States
  • 1998–2004
    • Tokyo Metropolitan University
      • Department of Applied Chemistry
      Tokyo, Tokyo-to, Japan