scholarly journals Elisa and HPLC analyses of deoxynivalenol in maize and wheat

Author(s):  
Jovana Matic ◽  
Igor Jajic ◽  
Bojana Saric ◽  
Aleksandra Misan ◽  
Sasa Krstovic ◽  
...  

Deoxynivalenol (DON) is a part of the family of mycotoxins called trichothecenes which are produced by a number of different Fusarium mold species. The presence of DON in 25 wheat and 25 maize samples was examined by Enzyme Linked Immunosorbent Assay (ELISA) and High Performance Liquid Chromatography (HPLC) methods. The presence of DON was detected and determined in 5 (20%) maize and 6 (25%) wheat samples by both of the methods. Correlation between ELISA and HPLC results was established, with the correlation coefficients (r) of 0.9691 and 0.9735 for wheat and maize samples, respectively. The results obtained by ELISA method were significantly higher than those obtained by HPLC method. This fact can be explained by the presence of conjugated or masked mycotoxins in the samples, especially DON-3-glucoside (DON-3-Glc), which could not be determined by HPLC method due to the lack of external standards. Contrary to this, being insufficiently selective towards masked DON, ELISA method measures total DON content of a sample. According to the obtained results, ELISA can be used as a reliable screening method, but the confirmation of positive results must be done by HPLC method.

1996 ◽  
Vol 59 (8) ◽  
pp. 893-897 ◽  
Author(s):  
ERIC W. SYDENHAM ◽  
SONJA STOCKENSTRÖM ◽  
PIETER G. THIEL ◽  
JOHN P. RHEEDER ◽  
M. BRUNO DOKO ◽  
...  

The performance of an experimental polyclonal antibody (PAb)-based competitive direct enzyme-linked immunosorbent assay (CD-ELISA) developed for the analysis of fumonisins in corn was assessed by comparison with an established high-performance liquid chromatography (HPLC) method. The comparative study was conducted using a series of 20 corn samples naturally contaminated with combined fumonisin levels ranging from <0.05 to >5 μg/g (ppm). Linear regression analysis between the results generated by HPLC and CD-ELISA provided correlation coefficients (r) and regression slopes (b) of r = 0.960, b = 1.493 (P < 0.001); r = 0.865, b = 3.903 (P < 0.001); and r = 0.832, b = 0.107 (P < 0.001) for the individual fumonisins B1 (FB1), B2 (FB2) and B3 (FB3), respectively, while corresponding values of r = 0.967, b = 1.059 (P < 0.001) were obtained for the combined FB1, FB2, and FB3 concentrations. In 3 of 18 fumonisin-positive corn samples, combined fumonisin levels determined by CD-ELISA were between 85 and 100% higher than those determined in the same extracts by HPLC, while in 13 other samples, CD-ELISA results were between 1.8 and 53% higher than those determined by HPLC. Conversely, in 2 of 18 samples, CD-ELISA results were lower than those determined by HPLC. The differences recorded between HPLC and the experimental PAb-based CD-ELISA were far less than those previously recorded for other mono- and polyclonal antibody-based CD-ELISA systems. The results indicate that the experimental PAb-based CD-ELISA may be effectively applied for the initial screening for fumonisins in corn.


2007 ◽  
Vol 50 (2) ◽  
pp. 349-359 ◽  
Author(s):  
Simone Fujii ◽  
Elisabete Yurie Sataque Ono ◽  
Ricardo Marcelo Reche Ribeiro ◽  
Fernanda Garcia Algarte Assunção ◽  
Cássia Reika Takabayashi ◽  
...  

An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for ochratoxin A (OTA) detection in green, roasted and instant coffees was developed using anti-OTA monoclonal antibody. Immunological reagents prepared were OTA-BSA (4.76 mg/mL), anti-OTA.7 MAb (2x10³-fold dilution) and HRP-anti IgG (10³-fold dilution). The detection limit was 3.73 ng OTA/g and correlation coefficients (r) between this immunoassay and high performance liquid chromatography were 0.98 for green coffee, 0.98 for roasted and 0.86 for instant. OTA levels detected by ic-ELISA were higher than by HPLC, with ELISA/HPLC ratio of 0.66 - 1.46 (green coffee), 0.96 - 1.11 (roasted) and 0.93 - 1.82 (instant). ELISA recoveries for OTA added to coffee (5 - 70 ng/g) were 81.53 % for green coffee, 46.73 % for roasted and 64.35 % for instant, while recoveries by HPLC were 80.54 %, 45.91 % and 55.15 %, respectively. Matrices interferences were minimized by samples dilution before carrying out the ELISA assay. The results indicate that MAb-based ic-ELISA could be a simple, sensitive and specific screening tool for OTA detection, contributing to quality and safety of coffee products.


INDIAN DRUGS ◽  
2015 ◽  
Vol 52 (08) ◽  
pp. 12-16
Author(s):  
S Vidyadhara ◽  
◽  
L. S Reddyvalam ◽  
T. Koduri ◽  
P. K. Borra ◽  
...  

A simple, accurate, precise high-performance liquid chromatographic (HPLC) method has been developed and validated for the simultaneous determination of abacavir sulphate (ABA) and lamivudine (LAM) in combined dosage form. Separation was performed on a C18 column [Agilent ODS UG 5 column, 250 mm x 4.5 mm], with methanol: water (50:50 V/V) isocratic elution using a flow rate of 1mL/min. Good sensitivity was observed with UV detection at 277 nm. After method development, the interference of other active compounds and excipients, repeatability and linearity, were investigated. Retention times of LAM and ABA were found to be 3.3 and 6.3 min, respectively. The method was validated over the range from 2.5-12.5 μg/mL for LAM and 5-25 μg/mL for ABA with correlation coefficients of 0.9997 and 0.9996, respectively. This method was shown to be accurate, robust, selective, linear, and repeatable and can be successfully employed in routine quality control for the simultaneous analysis of ABA and LAM in tablets.


2018 ◽  
Vol 101 (6) ◽  
pp. 1961-1966 ◽  
Author(s):  
H H Wendy Yang ◽  
Adrian Weisz

Abstract Specifications in the U.S. Code of Federal Regulations for the color additive D&C Red No. 17 (R17, Colour Index No. 26100) limit the levels of the dye’s intermediates, aniline (AN), 2-naphthol (β-naphthol, BN), and 4-aminoazobenzene (4AAB), to 0.2, 0.2, and 0.1%, respectively. The present work reports the development and application of an ultra-HPLC method for the quantitative determination of these impurities in R17. A 1.7 μm particle size C-18 column was used with 0.2 M ammonium acetate and acetonitrile as the eluents. AN, BN, and 4AAB were quantified by using six-point calibration curves with data points (w/w) ranging from 0.01 to 0.25% for AN, 0.01 to 0.24% for BN, and 0.01 to 0.19% for 4AAB. The correlation coefficients ranged from 0.9992 to 0.9999. Limits of detection for the analytes ranged from 0.002 to 0.01%. Recoveries of the analytes ranged from 99.5 to 102%. Relative standard deviations ranged from 0.482 to 1.262%. The new method was applied to analyze portions from 22 batches of R17 submitted to the U.S. Food and Drug Administration for certification. It was found to be simpler to implement, faster, and more sensitive than the older gravity-elution column chromatography method, which it has replaced.


1996 ◽  
Vol 59 (9) ◽  
pp. 992-997 ◽  
Author(s):  
FENG-YIR YU ◽  
FUN S. CHU

Polyclonal antibodies against fumonisin B1 (FmB1) were produced in rabbits after immunizing the animals with either FmBl-keyhole limpet hemocyanin (KLH) or FmB1 bovine serum albumin (BSA). A direct competitive enzyme-linked immunosorbent assay (dc-ELISA) and an indirect competitive ELISA (idc-ELISA) were used for the characterization of the antibodies and for analysis of the toxin in corn samples. The antibody titers in the serum of rabbits immunized with FmBl-KLH were considerably higher than in those immunized with FmBl-BSA. The antibodies from the rabbits immunized with FmBl-KLH were further characterized. The concentrations causing 50% inhibition of binding of FmB1-horseradish peroxidase (HRP) to the antibodies by FmB1, FmB2 and FmB3 in the ELISA were found to be 0.45, 0.72, and 25 ng/ml, respectively. The detection limit of FmBl, based on 95% confidence at 5% of inhibition of binding of FmBl-HRP conjugate, in buffer of the dc-ELISA was found to be 0.05 ng/ml. In the presence of a matrix such as corn, the detection limit was less than 50 ppb. The overall analytical recoveries of FmBl (50 to 1,000 ng/g) added to the ground corn and then extracted with CH3CN/H2O (1/1, vol/vol) with cleanup and without cleanup in the dc ELISA were found to be 70.5 and 85.9%, respectively. A good correlation was found between the FmBl levels in 2 starch and 10 naturally contaminated corn samples analyzed by the dc-ELISA and the high-pressure liquid chromatography (HPLC) method. The correlation coefficients between ELISA and HPLC were found to be 0.955 (y [ELISA] = 1.3 1x [HPLC] + 77 ppb; P < 0.001) and 0.811 (y = 1.13x + 34 ppb; P < 0.01) for the sample without and with cleanup treatment, respectively.


2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Hong Yan ◽  
Pei Xu ◽  
Hai Huang ◽  
Juan Qiu

AbstractA pre-column derivatized high-performance liquid chromatographic (HPLC) method with ultraviolet-visible detection was developed to measure the concentrations of spectinomycin in fermentation broth. Derivatization reagents, 2,4-dinitrophenylhydrazine in acetonitrile (5 mg mL−1) and trifluoroacetic acid in acetonitrile (0.8 mol L−1), were added to an aliquot of the fermentation broth, and the mixture was incubated for 60 min at 70°C. The resulting derivative was separated from other compounds by isocratic elution in a reversed-phase column Zorbax SB-C18 (250 mm × 4.6 mm, 5 µm). Mobile phase consisted of acetonitrile, tetrahydrofuran, and water (φ r = 40: 35: 25) and the flow rate was 1.0 mL min−1. The detection wavelength was 415 nm. The standard curve for spectinomycin sulfate was linear with correlation coefficients of 0.9997 in the range of 25 µg mL−1 to 600 µg mL−1. The relative standard deviation values ranged from 0.43 % to 2.18 % depending on the concentration of samples. The average recovery was 101.5 %. The limit of detection was 50 ng mL−1.


2005 ◽  
Vol 10 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Bong-Suk Jin ◽  
Won-Kyu Lee ◽  
Kwangseog Ahn ◽  
Myung Kyu Lee ◽  
Yeon Gyu Yu

The HIV-1 envelope glycoprotein transmembrane subunit, gp41, mediates the fusion of viral and target cell membranes. The 2 helical regions in the ectodomain of gp41, the N-helix and the C-helix, form a helical bundle complex that has been suggested as a fusion-active conformation. Previously, an enzyme-linked immunosorbent assay (ELISA) method had been established to measure the interaction of 2 helical regions of gp41. In this study, the ELISA method was modified to apply high-throughput screening (HTS) of an organic compound library. A few compounds had been identified to prevent the interaction between 2 helical regions of gp41, and they were further shown to inhibit the gp41-mediated viral infection. In addition, they specifically quenched the fluorescence of tryptophan in the N-helix region, indicating that these compounds bound to the N-helix rather than the C-helix of gp41. These results suggested that this assay method targeting gp41 could be used for HTS of HIV fusion inhibitors. ( Journal of Biomolecular Screening 2005:13-19)


Author(s):  
Biljana Gjorgjeska

Ketoconazole has been widely used as an antifungal drug  that is formulated as tablets, cream and over­the­counter ketoconazole shampoo. The aim of this research was to study and to standardize an ultraviolet spectrophotometric (UVS) method, potentiometric  and a high  performance  liquid  chromatographic  (HPLC) method  for  the determination  of ketoconazole in commercially available Oromycosal® tablets. These three methods were compared and discussed with respect to  their  sensitivity,  selectivity  and ready­applicability  in  routine  analytical  work.   Absorption  spectra and spectrophotometric determinations were carried out on the UVS spectrophotometer. Investigated concentrations were in range from  0.003 to  0.02mg?dm­3. The absorbance was measured at 224  nm.  In potentiometric  titrations  glass  and saturated (KCl) calomel electrode were used. HPLC analyses of ketoconazole were carried in the presence of econazole as internal standard. It can be concluded that the described methods are simple, fast and reliable for determination of ketoconazole in pharmaceutical preparations. The preparation of the samples is easy, the excipients do not  interfere in the methods, so they can be used in routine quality control analysis.


2019 ◽  
Vol 11 (1) ◽  
pp. 52 ◽  
Author(s):  
Any Guntarti ◽  
Endah Nurvita Hutami

Crystal guava contains high vitamin C. Vitamin C is contained in different fruits, one of the factors is the altitude of the fruit plant growing areas. This study aims to determine the level of vitamin C in the slurry of crystal guava flesh with variations of origin using the HPLC method. Samples of crystal guava are obtained from the city of Bogor, Malang, and Gunung Kidul. The samples to be analyzed are prepared as a slurry. Qualitative analysis is done by identification using KMnO4 p.a, FeCl3 p.a, AgNO3 p.a as well as comparing the retention time of the sample with vitamin C. Method validation for system suitability, linearity and precision provide results that are eligible according to the applicable regulations. Quantitative analysis using HPLC with C18 stationary phase, water: methanol mobile phase (95: 5) v/v, flow rate of 1 mL/min, and run time of 7.5 minutes. Qualitative analysis by using KMnO4, FeCl3, AgNO3, and retention time (tR) shows positive results of the vitamin C existence. The average levels of vitamin C from Bogor, Malang, and Gunung Kidul, equal to (0.4139 ± 0.004) mg/mL; (0.6746 ± 0.03) mg/mL; and 0.8608 ± 0.002 mg/mL respectively.


Author(s):  
Rajesh R. ◽  
JITHU JERIN JAMES

Objective: To develop a simple, accurate and precise reverse-phase high-performance liquid chromatography (RP-HPLC) method and subsequently validate for the simultaneous estimation of praziquantel (PZQ) and pyrantel pamoate (PP) in the pharmaceutical dosage form. Methods: The chromatographic separation was achieved on Phenomenex Luna C18 column (250 mm × 4.6 mm, 5 μm) as stationary phase maintained at an ambient temperature with a mobile phase comprising of water: acetonitrile (20: 80) at a flow rate of 1.0 ml/min and UV detection at 220 nm. Results: The retention time of PZQ and PP was found to be 3.897 min and 1.697 min respectively. The method was validated in terms of specificity, accuracy, precision, linearity and robustness as per ICH guidelines. Linearity was obtained in the concentration range of 20–60 μg/ml for both PZQ and PP with correlation coefficients of 0.987 and 0.998 respectively. The accuracy of the method was determined using a recovery test and found as 98.44 % to 100.35 %. All parameters are found to be within the acceptable limit. Conclusion: The developed RP-HPLC method was simple, rapid, accurate, precise for the simultaneous estimation of PZQ and PP in bulk and tablet dosage form.


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