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1.
Ch. Noonpudgee 《Chromatographia》1987,23(1):47-49
Summary A method is described for the determination of deoxynivalenol (DON) in maize and corn silage with a detection limit by UV of 0.2 ppm after a simple separation by means of connected reversed-phase columns. 相似文献
2.
Determination of deoxynivalenol (vomitoxin) by high-performance liquid chromatography with electrochemical detection 总被引:2,自引:0,他引:2
V L Sylvia T D Phillips B A Clement J L Green L F Kubena N D Heidelbaugh 《Journal of chromatography. A》1986,362(1):79-85
A rapid method for the analysis of deoxynivalenol (DON) was developed using high-performance liquid chromatography (HPLC) with reductive electrochemical detection (ED). Deoxynivalenol produced by Fusarium roseum growing on solid cornmeal and rice substrates and from naturally contaminated wheat was extracted and quantitated via ED. DON levels in wheat were verified by gas chromatography and structurally confirmed by mass spectrometry. DON was optimally resolved by HPLC employing a radially compressed octadecylsilane column and a mobile phase of deoxygenated methanol-40 mM borate buffer (35:65) at a flow-rate of 1.0 ml/min. Under these conditions DON exhibited an average retention time of 3.6 min. Reductive ED (-1.4 V) allowed a 12-fold increase in sensitivity and greater selectivity than classical UV absorption at 224 nm. A detection limit for DON of 25 pg/microliter was achieved under these conditions. The determination of DON in crude grain extracts was hindered by extractable interfering substances, whereas ED was more functional-group selective (i.e. reduction of the carbonyl moiety). ED permits a direct quantitation of DON from crude grain extracts and may facilitate the determination of this agent and associated metabolites in biological samples. 相似文献
3.
Analysis of zearalenone and α-zearalenol in animal feed using high-performance liquid chromatography
Different extraction and clean-up techniques used before HPLC analysis were compared in order to obtain a reliable method for the quantitative determination of zearalenone (ZEA) and α-zearalenol (α-ZOL) in animal feed. Immunoaffinity clean-up was compared to C18 and Florisil column clean-up. Extracted samples were analysed by reversed-phase HPLC with fluorescence detection (λex=274 nm, λem=440 nm). A mobile phase of acetonitrile:water (50:50 (v/v)) and a flow-rate of 1.0 ml min−1 resulted in a good separation between ZEA and α-ZOL. Using immunoaffinity clean-up the linear range was between 25 and 600 μg kg−1 for ZEA and α-ZOL in maize. Intra-laboratory coefficients of variation (CV) (under repeatability conditions) were 9.16% for ZEA and 2.18% for α-ZOL. Recoveries for spiked ZEA and α-ZOL samples ranged from 89 to 110% with CVs between 5.2 and 11.2% (under within-laboratory reproducibility conditions). Using C18 and Florisil solid-phase clean-up, matrix interference was too high. Therefore, naturally contaminated animal feed samples were analysed using the developed HPLC method coupled to the immunoaffinity clean-up. 相似文献
4.
Summary An efficient procedure for the extraction and analysis of ochratoxins A, B, C and α from buffered rumen fluid has been developed.
The samples have been cleaned up byliquid-liquid extraction and the separation of chratoxins was by isocratic elution on a
5μm C18 ODS-column which 0.083 M phosphoric acid/acetonitrile/isopropanol (55/35/10). 相似文献
5.
6.
E.F. Moazami 《Microchemical Journal》2009,93(1):25-28
In this first study performed in noodle samples consumed in Malaysia for the presence of deoxynivalenol (DON), a total of 135 sample of noodles, comprised of instant noodle, yellow alkaline noodle and white salted noodle, were randomly collected from food stores and analyzed for DON using high performance liquid chromatography (HPLC) with a PDA (photodiode array) detector at 218 nm. The objective of this study was to investigate the DON contamination levels in different types of wheat-based noodle consumed in Peninsular Malaysia. An acetonitrile:water (17:83 v/v) mixture was used as a mobile phase and clean-up was accomplished with a Mycosep 225 column. There was a high variation in the DON concentrations in all types of noodle group as well as between brands. Only one sample of instant and yellow alkaline noodle each were contaminated with DON, at concentrations of 1.003 and 1.243 ng/g, respectively. The minimum detectable concentration for the DON was 0.627 ng/g in instant noodle. In the case of white salted noodle, none of the samples contained any detectable amount of DON. The results indicate a low occurrence of DON mycotoxins in commercial noodle products in Malaysia. 相似文献
7.
Qiuhua Wu Yuqin Su Lihua Yang Jingci Li Jingjun Ma Chun Wang Zhengping Li 《Mikrochimica acta》2007,159(3-4):319-324
A method was developed for the determination of polyamines (PA) by high-performance liquid chromatography with chemiluminescence
detection. It is based on the unsaturated complex of PA with Cu(II) which had a strong catalytic effect on the luminol-H2O2 chemiluminescence reaction. The separation of PA was carried out on a reveres phase C18 column using methanol/water (25/75,
v/v) as a mobile phase. The method was applied to the analysis of putrescine and the total amount of spermine and spermidine
in apple leaves and strawberry fruit. The results indicated that the method is practical and useful. 相似文献
8.
Shen X Boswell CA Wong EH Weisman GR Anderson CJ Tomellini SA 《Biomedical chromatography : BMC》2006,20(1):37-47
The use of copper radioisotopes in imaging and therapy has prompted an increased interest in chelators which form stable copper complexes, such as Cu(II)-azamacrocyclic complexes. The effects of charge, stability and the size of the macrocyclic backbone of the Cu(II)-azamacrocyclic complexes on biological behavior have been evaluated. Here we report a reversed-phase high-performance liquid chromatography (HPLC) method to separate several Cu(II)-azamacrocyclic complexes, including Cu(II) complexes of 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid (TETA), 4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane (CB-TE2A) and 4,10-bis(carboxymethyl)-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane (CB-DO2A). Absorbance at 280 nm was used to monitor the complexes as they eluted from the reversed-phase column. The effects of the concentration of the buffer, the pH of the buffered mobile phase and the concentration of the organic modifier, methanol, on the separation were investigated. Separation of these copper complexes by ion-pair HPLC with the use of a mass spectrometry-compatible ion-pair reagent, triethylammonium acetate, in the mobile phase at pH 6.3 is also presented. The reversed-phase chromatographic conditions utilized also allow the pK(a)s of Cu-TETA and the log(k'w) values of Cu-CB-TE2A, Cu-TETA and Cu-CB-DO2A to be estimated. 相似文献
9.
S Borràs JG Ríos-Kristjánsson R Companyó MD Prat 《Journal of separation science》2012,35(16):2048-2053
An analytical method for the analysis of six fluoroquinolones (FQs) in animal feeds was developed. The sample treatment consists of a simple and rapid extraction of the analytes by manual shaking with an acetonitrile-water mixture containing hydrochloric acid without further sample cleanup. Matrix effects were minimized by diluting the extract with water. Determination was carried out by liquid chromatography using fluorimetric detection. The method was validated in-house in four different feed matrices (poultry, cow, pig, and lamb feed). Mean recoveries ranging from 80 to 105%, with relative standard deviations below 12%, were achieved from spiked animal feed samples on the 0.2-2.0 μg/g level. No relevant differences were observed between the studied feeds, this ensuring that the method was reliable for a wide variety of feed matrices. Decision limit and detection capability values are below 0.08 and 0.13 mg/kg, respectively, for most FQs. The results obtained demonstrate the feasibility of the analytical method developed for a routine use to control the illegal use of these substances in feeding stuffs. 相似文献
10.
The synthesis and evaluation of a molecularly imprinted polymer (MIP) used as a selective solid-phase extraction sorbent and
coupled to high-performance liquid chromatography (HPLC) for the efficient determination of sulfamerazine (SMR) in pond water
and three fishes are reported. The polymer was prepared using SMR as the template molecule, methacrylic acid as the functional
monomer and ethylene glycol dimethacrylate as the crosslinking monomer in the presence of tetrahydrofuran as the solvent.
The SMR-imprinted polymers and nonimprinted polymers were characterized by FT-IR and static adsorption experiments. The prepared
SMR-imprinted material showed a high adsorption capacity, significant selectivity and good site accessibility. The maximum
static adsorption capacities of the SMR-imprinted and nonimprinted materials for SMR were 108.8 and 79.6 mg g−1, respectively. The relative selectivity factor of this SMR-imprinted material was 1.6. Several parameters influencing the
solid-phase extraction process were optimized. Finally, the SMR-imprinted polymers were used as the sorbent in solid-phase
extraction to determine SMR in pond water and three fishes with satisfactory recovery. The average recoveries of the MIP-SPE
method were 94.0% in ultrapure water and 95.8% in pond water. Relative standard deviations ranging from 0.3% to 5.2% in MIP
were acquired. The results for the SMR concentrations in crucian, carp and wuchang fish were 66.0, 127.1 and 51.5 ng g−1, respectively. The RSDs (n = 5) were 3.51%, 0.53% and 5.08%, respectively. The limit of detection (LOD) for SMR was 1 ng g−1 and the limit of quantitation (LOQ) was 3.5 ng g−1. 相似文献
11.
A novel method has been developed for simultaneous analysis for three pairs of trans- and cis-isomers of 2-glucosyloxycinnamic acids, along with their biogenic metabolites (three coumarin derivatives including scopoletin, scoparone and ayapin) in a Chinese medicinal herb Dendrobium thyrsiflorum by using high-performance liquid chromatography (HPLC)-photodiode array detection (DAD)-electrospray ionization (ESI)-tandem mass spectrometry (MS). The method was carried out by using a Polaris C18 column with a gradient solvent system of 0.5% acetic acid aqueous solution-acetonitrile. Seven target analytes including isodensifloside, isothyrsifloside, densifloside, thyrsifloside, scoparone, ayapin and scopoletin were exclusively identified by comparing their retention behaviors, UV and MS spectra with the authentic standards, and their contents in D. thyrsiflorum were simultaneous determined by employing UV detection at 342 nm. In addition, another pair of isomers of 2-glucosyloxycinnamic acids was putatively elucidated mainly based on the MS fragmentation. The method was validated and found to be satisfactorily linear, selective and robust. Recoveries ranged from 95.56 to 97.94% for all compounds at three different spiking levels. The limits of detection (LOD) and quantitation (LOQ) ranged, respectively, from 0.02 to 0.13 μg mL−1 and 0.07 to 0.39 μg mL−1 depending on various compounds. The established quality evaluation method was successfully used for evaluating the quality of D. thyrsiflorum samples of different organs and collections. 相似文献
12.
Paweł Płocharz Anna Klimek-TurekTadeusz H. Dzido 《Journal of chromatography. A》2010,1217(29):4868-4872
Kinetic performance, measured by plate height, of High-Performance Thin-Layer Chromatography (HPTLC), High-Performance Liquid Chromatography (HPLC) and Pressurized Planar Electrochromatography (PPEC) was compared for the systems with adsorbent of the HPTLC RP18W plate from Merck as the stationary phase and the mobile phase composed of acetonitrile and buffer solution. The HPLC column was packed with the adsorbent, which was scrapped from the chromatographic plate mentioned. An additional HPLC column was also packed with adsorbent of 5 μm particle diameter, C18 type silica based (LiChrosorb RP-18 from Merck). The dependence of plate height of both HPLC and PPEC separating systems on flow velocity of the mobile phase and on migration distance of the mobile phase in TLC system was presented applying test solute (prednisolone succinate). The highest performance, amongst systems investigated, was obtained for the PPEC system. The separation efficiency of the systems investigated in the paper was additionally confirmed by the separation of test component mixture composed of six hormones. 相似文献
13.
A highly selective and sensitive detection method based on tris(2,2′-bipyridyl)ruthenium(II) [Ru(bpy)32+] electrogenerated chemiluminescence (ECL) has been developed for the quantitative determination of β-blockers in both pharmaceutical preparations and human urine samples. The ECL emission is based on the reaction between electro-oxidized Ru(bpy)33+ and the secondary amino groups on the β-blockers. The ECL intensities for the β-blockers were strongly dependent on the pH at which the ECL detections were conducted, with the maximum intensities being obtained at pH 9.0. Under the optimal condition, the detection limit for atenolol and metoprolol were almost 0.5 μM (50 pmol) and 0.08 μM (8 pmol), respectively, with S/N of 3 and a linear working range that extends four orders of magnitude with relative standard deviations below 5% for 10 replicate injected samples. The concentrations of atenolol and metoprolol were determined in pharmaceutical preparations using flow injection analysis with Ru(bpy)32+ ECL detection based on standard addition method. The determined values by the present method showed acceptable agreement with the stated values by manufacturers. The determination of the five β-blockers in human urine samples was performed using HPLC-Ru(bpy)32+ ECL detection. The resulting chromatogram was much simpler than that obtained with HPLC-UV absorbance detection. 相似文献
14.
15.
Formose sugar and formaldehyde (HCHO) were analyzed using high-performance liquid chromatography (HPLC) utilizing a CarboPac PA1 column (Dionex) and pulsed amperometric detection. This HPLC system was unsuitable for the analysis of formose sugar and HCHO and thus reducing sugars and unconverted HCHO were determined by endowing them with charges through a derivatization method using 2,4-dinitrophenylhydrazine. The separation and detection of compounds were performed by three Chromolith RP-C18 columns (Merck) and diode array detection, at a wavelength of 360 nm ultraviolet light, respectively. Lower sugars (except HCHO) showed some instabilities when the derivatized samples were kept for the extended periods of time. For C5 and consecutive higher sugars, a certain derivatization time was necessary. In the present case (formose reaction with partial HCHO conversion), approximately 18 h may be a reasonable compromise for the derivatization reaction. A derivatization agent to compound mole ratio of up to 100:1 was required to complete the derivatization of C4 and higher sugars. However, the analysis of C4 and consecutive higher sugars is problematic for example due to overlapping of peaks or branched-chain sugars. 相似文献
16.
Xianchuan Xie Fang Yao Yingxin Wu 《International journal of environmental analytical chemistry》2013,93(12):1417-1428
A simple and sensitive method has been developed and validated for the determination of abamectin B1a (ABA B1a), emamectin B1a (EMA B1a) benzoate and ivermectin H2B1a (IVM H2B1a) in soils. The avermectins (AVMs) residues were extracted from soils with acetonitrile/water (9?:?1, v/v) and then were purified on C18 solid-phase extraction (SPE) cartridge. After being derivatised by N-methylimidazole (N-MIM) and trifluoroacetic anhydride (TFAA), the residues of three AVMs were analysed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The method was validated in terms of system suitability, linearity, selectivity, precision, recovery, specificity and stability. There was a good linear relationship (R 2?>?0.99) for three AVMs ranged from 0.01 to 5?µg?mL?1. The LOD and LOQs of ABA B1a, EMA B1a benzoate and IVM H2B1a for standard solutions were 1.1–1.7 and 3.6–5.7?µg?L?1 respectively. The accuracy of AVMs in soils was from 83.7 to 115.5% with precision less than or equal to 12.4%. Using the developed method, 9 soil samples with 9.3–12806.3?µg?kg?1 of AVMs residues had been detected. 相似文献
17.
Anandamide (N-arachidonylethanolamine) is an endogenous cannabinoid receptor ligand that has been implicated in various physiological and pathophysiological functions. In the present study, a liquid-liquid extraction-based reversed-phase HPLC method with fluorometric detection was validated and applied for the analysis of anandamide in human plasma. Following derivatization with the fluorogenic reagent 4-(N,N-dimethylaminosulfonyl)-7-(N-chloroformylmethyl-N-methyl-amino)-2,1,3-benzoxadiazole (DBD-COCl), the analyte was separated using an acetonitrile-water gradient at a flow rate of 0.8 mL/min, and spectrophotometric detection at 560 nm with an excitation wavelength of 450 nm. The retention times for anandamide and R+-methanandamide (internal standard) were 27.1 and 30.7 min, respectively. The validated quantification range was 1-15 ng/mL. The developed procedure was applied to determine anandamide levels in human plasma following a 24 h incubation of human whole blood at 37 degrees C in the presence or absence of phenylmethylsulfonyl fluoride, an inhibitor of the anandamide-degrading enzyme fatty acid amide hydrolase. Anandamide levels determined under both conditions were within the validated concentration range with anandamide levels being 2.3-fold higher in plasma from PMSF-treated blood. 相似文献
18.
Estevinho BN Ferraz A Rocha F Alves A Santos L 《Analytical and bioanalytical chemistry》2008,391(4):1183-1188
The purpose of this work was to quantify glucose in aqueous solutions containing chitosan by high-performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD). Chitosan is a natural compound that is used alone or as an additive in several formulations. Microencapsulation of bioactive compounds such as glucose, by means of chitosan, is being explored, but difficulties arise when glucose needs to be determined in the presence of chitosan. HPLC is the technique most commonly used for glucose analysis, and ELSD may offer advantages (e.g. sensitivity and the possibility of operating in gradient mode) compared with other detectors. The influence of chitosan in the analysis of glucose by HPLC with ELSD was investigated at different pH values of the aqueous solutions. Isocratic elution with an acetonitrile/water mixture (80:20, v/v) and water washing between runs were the best options to avoid the mucoadhesive properties of chitosan, which are responsible for column degradation and variability of the retention time of glucose. The developed methodology was considered completely adequate for rapid glucose analysis in aqueous solutions with low pH (< 3), in the presence of chitosan. 相似文献
19.
Summary The feasibility of reversed-phase high-performance liquid chromatography for the separation of several metal complexes ofmeso-tetrakis(p-tolyl)porphine (TTP) is described. A combination of an octadecyl-bonded stationary phase with a non-aqueous polar mobile phase, such as an acetone-acetonitrile mixture, has proved effective for the separation. Thus, the TTP complexes of Mg, VO, Ni, Cu, Zn, and Pd and also TTP free acid were successfully separated in about 10min on a Li-Chrosorb RP-18 column (7m, 250×4mm i.d.) with a 7030 (vol/vol) mixture of acetone and acetonitrile at a flow-rate of 1 mlmin–1. 相似文献
20.
Summary Separation and determination ofFusarium trichothecenes: nivalenol, deoxynivalenol, fusarenone and 3-acetyldeoxynivalenol, were carried out by highperformance liquid chromatography with UV detection, and methanol—water (30/70) as mobile-phase on Lichrosorb RP-18 column. Detection limits were 2, 3, 3 and 5ng per injection of nivalenol, deoxynivalenol, fusarenone and 3-acetyldeoxynivalenol, respectively. The method appears to be adequate for detection of the above trichothecenes in contaminated corn and rice as well as in cultures ofFusarium spp. A preliminary TLC purification was necessary for detection of fusarenone in corn. 相似文献