scholarly journals Determination of fumonisins B1 and B2 in beer

2011 ◽  
Vol 23 (No. 1) ◽  
pp. 20-26 ◽  
Author(s):  
Ľ. Daško ◽  
D. Rauová ◽  
E. Belajová ◽  
M. Kováč

The aim of this study was to investigate the contamination of beer of Slovak origin with fumonisins. A suitable analytical procedure was suggested &ndash; the limit of detection at the level close to 1 &micro;g/l was achieved for both fumonisins B<sub>1</sub> and B<sub>2</sub>. The recovery was determined at 93% for fumonisin B<sub>1 </sub>and at 78% for fumonisin B<sub>2</sub>. Fluorescence detection was used after derivatisation with a mixture of o-phthaldialdehyde and 2-mercaptoethanol. Phosphate buffer usually applied resulted in a poor separation of derivatised fumonisins. Peak splitting was observed depending on the pH of the eluent. The pH value of 2.6 was found suitable for the peak splitting elimination. A convenient gradient elution metod was suggested avoiding the possible interference in fumonisin contents determination. For the preparation of samples, immunoaffinity cleaning procedure was applied. Beer samples from all domestic producers were analysed. The content of fumonisins determined was under the limit of detection in all cases. All the beers tested were produced from the barley grown in 2003. &nbsp;

1997 ◽  
Vol 80 (4) ◽  
pp. 751-755 ◽  
Author(s):  
Theresa A Gehring ◽  
Larry G Rushing ◽  
Harold C Thompson

Abstract Fourteen sulfonamides—sulfanilamide, sulfadiazine, sulfathiazole, sulfapyridine, sulfam- erazine, sulfamethazine, sulfamethizole, sulfamethoxypyridazine, sulfachloropyridazine, sulfamonomethoxine, suļfadoxine, sulfamethoxazole, sulfadimethoxine, and sulfaquinoxoline—residues of which could be found in aquacultured species, were separated in &lt;25 min by reversed-phase (C18) liquid chromatography (LC) with gradient elution. Analytes were extracted from edible salmon tissue (muscle and adhering skin) with acetonitrile—2% aqueous acetic acid, isolated with 2 liquid-liquid partitionings, and derivatized with fluorescamine after eluting from the column. The derivatives were detected by fluorescence. Recoveries (n = 4) from coho salmon fortified with sulfonamides at 5,10, and 20 ng/g tissue averaged 79.7± 7.3, 84.6 ± 7.7, and 88.2 ± 7.1%, respectively. Limits of quantitation were 5 ng/g tissue, for sulfanilamide, sulfamethoxypyridazine, and sulfaquinoxoline and 1 ng/g tissue for the remaining sulfonamides.


2000 ◽  
Vol 83 (4) ◽  
pp. 784-788 ◽  
Author(s):  
Kieran McCarthy ◽  
Claudia Hischenhuber ◽  
Neil Joyce ◽  
G Cherix ◽  
C Hischenhuber ◽  
...  

Abstract A liquid chromatographic (LC) method for the determination of total taurine in pet foods was evaluated in a collaborative study. Ten laboratories assayed 6 blind duplicate pairs of wet and dry pet foods. The taurine in the 6 sample pairs ranged from low (170 mg/kg) to high (2250 mg/kg) concentrations as is. Collaborators also assayed a sample of known taurine concentration for familiarization purposes. Samples were hydrolyzed to release bound taurine, which was subsequently converted to the dansyl derivative and quantitated by gradient-elution LC with fluorescence detection. Repeatability relative standard deviations, RSDr, ranged from 3.2 to 10.0%; reproducibility relative standard deviations, RSDR, ranged from 6.1 to 16.1%. The method has been adopted Official First Action status by AOAC INTERNATIONAL.


1986 ◽  
Vol 69 (5) ◽  
pp. 894-898 ◽  
Author(s):  
Renee W Bagneris ◽  
Jean A Gaul ◽  
George M Ware

Abstract A liquid chromatographic (LC) method was developed for the determination of zearalenone and zearalenol in grains and mixed animal feeds. Samples are extracted with chloroform and purified by a baseacid liquid-liquid partition. Zearalenone and zearalenol are separated by reverse phase LC and determined by fluorescence detection, excitation wavelength 236 nm with a 418 nm cutoff filter. The method was applied to the determination of zearalenone and zearalenol in 395 survey samples of corn, oats, barley, sorghum, silage, and finished feeds. The limit of detection is 10 ng/g for both toxins. The range of naturally occurring toxins found was 10-4000 ng/g. Average recoveries were 84% for zearalenone and 69% for zearalenol. Coefficients of variation were 24.6% for zearalenone and 30.8% for zearalenol for crop year 1980, and 28.3% for zearalenone and 22.0% for zearalenol for crop year 1981.


2021 ◽  
Vol 11 (1) ◽  
pp. 31530.1-31530.9
Author(s):  
Maryam Akhgari ◽  

Background: Drug abuse is spreading rapidly all over the world. Methadone and tramadol are among not only the most abused opioids but also important from the forensic point of view. Therefore, we need to devise a simple and sensitive method for the sample preparation and identification of abused drugs in postmortem specimens. Methods: A simple and rapid Dispersive Liquid-Liquid Microextraction (DLLME) technique coupled with Ultrahigh Performance Liquid Chromatography (UHPLC) was developed for the extraction and analysis of methadone and tramadol from postmortem vitreous humor samples. Different parameters affecting the extraction recovery, such as the type and volume of extraction and dispersion solvents, pH value, sensitivity, and specificity, were optimized and studied. Results: Under optimized conditions, the recovery ranges were 82.3%-89.6% and 85.4%-87.1% for methadone and tramadol, respectively. The linear range was 25-100 ng/mL for both methadone and tramadol with a correlation coefficient (R2) of more than 0.98. Limit of Detection (LoD) and Limit of Quantification (LoQ) were 3 and 8 ng/mL for methadone and 6 and 16 ng/mL for tramadol. The accuracy level of the methods for methadone and tramadol detection were 99.4%-100% and 99.7%-99.9%, respectively. The method was specific enough for the qualitative and quantitative determination of methadone and tramadol. Conclusion: The obtained results showed that DLLME combined with UHPLC is a fast and straightforward method for determining methadone and tramadol in postmortem vitreous humor specimens.


2017 ◽  
Vol 60 (4) ◽  
Author(s):  
Guadalupe Pérez-Caballero ◽  
Nancy Muro-Hidalgo ◽  
Elvia Adriana Morales-Hipólito ◽  
Alma Villaseñor ◽  
Raquel López-Arellano

A reversed phase high-performance liquid chromatography (RP-HPLC) method for determination of Thimerosal (TMS) in topical creams was optimized and validated according to the ICH guidelines which include accuracy, precision, selectivity, robustness, limit of detection (LOD), limit of quantification (LOQ), linearity and range. For topical creams, sample treatment is often an overwhelming step essentially due to its oily nature. For the first time a simple and robust extraction procedure for TMS using phosphate buffer (pH 5.5, 0.2M) was successfully developed. This method describes the TMS quantitation by HPLC in a topical product containing 0.01% fluocinolone acetonide (FLA) as the active molecule. The HPLC separation was achieved on a Column Symmetry® and a methanol: phosphate buffer (pH 2.5, 0.05M) 70:30 v/v mobile phase and wavelength 218 nm. Results from both standards and samples showed adequate validation parameters. Noteworthy, linearity was within the range 1.2 - 2.8 μg/mL. Additionally, robustness and TMS stability were established after sample extraction. The method provides an efficient and safe quality control tool for determination of TMS in topical creams.


Author(s):  
Mohamed M.A. Hamdy ◽  
Mona M. Abdel Moneim

AbstractTramadol, a strong pain killer known for its addictive problems is either co-administrated or co-formulated with other analgesics or muscle relaxants. The power of fluorescence detection in HPLC is tested to resolve such mixtures in plasma matrix to reach the required sensitivity with simple sample treatment using just protein precipitation. The aim of this work was to develop an eco-friendly and sensitive HPLC method with fluorimetric detection for analysis of Tramadol in its two binary mixtures with Ibuprofen (mixture 1) and Chlorzoxazone (mixture 2) in two combined dosage forms and spiked plasma. Separation was done using a C18 column with mobile phase of acetonitrile and water (pH 3.5) in gradient elution and 1 mL/min flow rate. Detection was carried out with λ excitation/λ emission of 220 and 307 nm, respectively. The method was applied to detect the two binary mixtures in real plasma samples after invivo application to rats, to assure that the drugs’ metabolites do not affect the sensitivity or selectivity of the assay. Evaluation of greenness of the proposed method was done using semi-quantitative Eco‐Scale and new Green Analytical Procedure Index which showed that this method can be a greener alternative with higher sensitivity for analysis of both mixtures. The method (15 min-assay) was linear over concentrations of 0.1–10 μg/mL and 0.1–33 μg/mL in plasma. In addition, the proposed method was validated per ICH as well as FDA bioanalytical methods’ validation guidelines.


Author(s):  
Biljana Stojanovska-Dimzoska ◽  
Zehra Hajrulai-Musliu ◽  
Elizabeta Dimitrieska-Stojkovic ◽  
Risto Uzunov ◽  
Pavle Sekulovski

Liquid chromatography with fluorescence detection using immunoaffinity column clean-up was a method described for determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2) in peanuts and peanut based products. The validation of the procedure was performed. Good coefficient of correlation was found for all aflatoxins in the range of 0.9993-0.9999. Limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.003-0.005 mg/kg and 0.009-0.023 mg/kg, respectively, which was acceptable. The mean recovery for total aflatoxins was 88.21%. The method also showed acceptable precision values in the range of 0.171-2.626% at proposed concentration levels for all four aflatoxins. RSDR values (within laboratory reproducibility) calculated from the results showed good correlation between two analysts for all aflatoxins and they ranged from 4.93-11.87%. The developed method was applied for the determination of aflatoxins in 27 samples of peanuts and peanut based products. The results showed that 21 peanut samples (77.7%) were below LOD of the method. Three samples had positive results over the MRL. There was one extreme value recorded for the total aflatoxins in peanut (289.2 mg/kg) and two peanut based products, peanut snack and peanut, with total content of aflatoxins being 16.3 mg/kg and 8.0 mg/kg, respectively. The obtained results demonstrated that the procedure was suitable for the de?termination of aflatoxins in peanuts and peanut based products and it could be implemented for the routine analysis.


2002 ◽  
Vol 48 (7) ◽  
pp. 1049-1058 ◽  
Author(s):  
Jifeng Liu ◽  
Weidong Cao ◽  
Haibo Qiu ◽  
Xiuhua Sun ◽  
Xiurong Yang ◽  
...  

Abstract Background: Capillary electrophoresis (CE) with tris(2,2′-bipyridyl)ruthenium(II) [Ru(bpy)32+]-electrogenerated chemiluminescence (ECL) detection is a promising method for clinical analysis. In this study, a method combining CE with Ru(bpy)32+ ECL (CE-ECL) detection that can be applied to amine-containing clinical species was developed, and the performance of CE-ECL as a quantitative method for determination of sulpiride in human plasma or urine was evaluated. Methods: Sulpiride was separated by capillary zone electrophoresis in uncoated fused-silica capillaries [50 cm × 25 μm (i.d.)] filled with phosphate buffer (pH 8.0) and a driving voltage of +15 kV, with end-column Ru(bpy)32+ ECL detection. A platinum disc electrode was used as working electrode. Sulpiride in human plasma or urine samples (100 μL) was extracted by a double-step liquid-liquid extraction procedure, dried under nitrogen at 35 °C in a water bath, and reconstituted with 100 μL of filtered water. The extraction solvent was ethyl acetate–dichloromethane (5:1 by volume). Results: Under optimum conditions (pH 8.0 phosphate buffer, injection for 6 s at 10 kV, and +1.2 V as detection potential), separation of sulpiride was accomplished within 4 min. The calibration curve was linear over a concentration range of 0.05–25.0 μmol/L, and the limit of detection was 2.9 × 10−8 mol/L for sulpiride. Intra- and interday CVs for ECL intensities were &lt;6%. Extraction recoveries of sulpiride were 95.6–101% with CVs of 2.9–6.0%. The method was clinically validated for patient plasma and urine samples. Conclusions: CE combined with Ru(bpy)32+ ECL is reproducible, precise, selective, and enables the analysis of sulpiride in human plasma and urine. It thus is of value for rapid and efficient analysis of amine-containing analytes of clinical interest.


2000 ◽  
Vol 83 (3) ◽  
pp. 698-713 ◽  
Author(s):  
Julie Fillion ◽  
François Sauvé ◽  
Jennifer Selwyn

Abstract A method is described for the determination of 251 pesticide and degradation product residues in fruit and vegetable samples. Extraction of the sample with acetonitrile is followed by a saltingout step. Co-extractives are removed by passing a portion of the acetonitrile extract through an octadecyl (C18) solid-phase extraction cleanup cartridge and then, in a second cleanup, through a carbon cartridge coupled to an amino propyl cartridge. Determination is by gas chromatography with mass-selective detection in the selected-ion monitoring mode, and by liquid chromatography with post-column reaction and fluorescence detection for N-methyl carbamates. The method has been used for analysis of various fruits and vegetables, such as apple, banana, cabbage, carrot, cucumber, lettuce, orange, pear, pepper, and pineapple. Limits of detection range between 0.02 and 1.0 mg/kg for most compounds. Over 80% of the compounds have a limit of detection of ≤0.04 mg/kg.


INDIAN DRUGS ◽  
2020 ◽  
Vol 57 (05) ◽  
pp. 71-73
Author(s):  
Aasha Patel ◽  
Sandip D. Firke ◽  
Ravindra R. Patil ◽  
Mohan G. Kalaskar ◽  
Sanjay B. Bari ◽  
...  

A novel RP-HPLC method was developed and validated for the determination of compounds in an oral solution. The method describes the determination of domperidone along with sodium methylparaben, sodium propylparaben and sodium benzoate in liquid oral formulation. Chromatographic separations were performed using BDS Hypersil 5 μm C18 column and gradient elution (solvent A: phosphate buffer, pH 3.5 and solvent B: methanol), keeping a flow rate of 1.5 mL/min. Detection was done at dual wavelength (232 nm for domperidone and sodium benzoate, and 257 nm for sodium methylparaben and sodium propylparaben). Analysis time was <17 min. The retention times for domperidone, sodium benzoate, sodium methylparaben and sodium propylparaben were found to be 10.0, 6.5, 8.0, and 13.5 min., respectively. The calibration curves for domperidone, sodium benzoate, sodium methylparaben and sodium propylparaben were found to be linear in the range of 250-750, 50-150, 50-150, and 5-15 μg/mL.


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