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In this study, we aimed to establish a method for determination of multiple mycotoxins such as aflatoxins, ochratoxin A, and zearalenone in red pepper powder samples based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach for extraction and cleanup, with detection and quantification by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in both positive- and negative-ion modes. The developed LC-MS/MS analytical method was compared with an enzyme-linked immunosorbent assay (ELISA) to improve the reliability of our developed method. The linearity, precision, and accuracy were validated for the LC-MS/MS methods. The results obtained with the LC-MS/MS were linear, with a correlation coefficient (R2) of >0.998. The limits of detection and quantification for mycotoxins were 0.07 to 0.71 μg/kg and 0.20 to 1.81 μg/kg, respectively. Intra- and interday precision tests (expressed as the relative standard deviation) for each analyte were 1.58 to 5.97% and 0.97 to 9.01%, respectively. Average recoveries were 85.70 to 94.99%. The validation results for the ELISA were linear (R2 > 0.995), and recoveries were 77.13 to 93.93%. Both analytical methods were applied to determine the presence of mycotoxins in commercial red pepper powder samples from South Korea. Four of the total 56 samples were contaminated with aflatoxins, and 6 samples were contaminated with ochratoxin A; these results were consistent for the two methods (P > 0.05). Therefore, our developed LC-MS/MS with QuEChERS approach for determination of multiple mycotoxins may be useful for controlling the quality and safety of red pepper powder. [ABSTRACT FROM AUTHOR]

The number of glyphosate intoxication cases has been increased after the regulation of paraquat. Unfortunately, there are no reports on the potential concentration of glyphosate for those acute intoxicated patients admitted to emergency rooms and the correlation between the concentration of glyphosate and clinical symptoms in Korea up to our knowledge. As a nonselective herbicide, analysis of glyphosate requires derivatization because of its amphoteric and strongly polar nature. In order to develop a method to determine the concentration of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA) in blood samples without derivatization, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was utilized with a hydrophilic interaction chromatography (HILIC) column. The validation of this method showed that the limits of detection (LODs) and limits of quantitation (LOQs) for glyphosate and AMPA were 50 and 100ng/mL, respectively. In addition, matrix effect, recovery rate, and accuracy and precision in intra and inter-day were evaluated during the validation study of this method. Blood samples acquired from five glyphosate intoxicated patients were analyzed to investigate the correlation between the concentration of glyphosate and clinical symptoms. These patients were previously admitted to the emergency room at a University Hospital in Korea after glyphosate was self-administered in suicide attempts or by accident. As results of blood sample study, the concentration of glyphosate and AMPA were found in the range of 1.0-171.1 and 0.2-2.6μg/mL, respectively. The concentration ratio of glyphosate to AMPA was 55-71. According to the clinical reports for those patients, they were in the age between 47 and 82 years old and administered about 50-400mL. The blood samples were collected within 2-5h after administration of glyphosate. Among the intoxicated patients, the most common clinical symptom was metabolic acidosis, identified in four patients. The comparison between the concentration of glyphosate and administered dosage did not show the correlation, which suggests further investigation on the effects of surfactants in glyphosate from different vendors. [ABSTRACT FROM AUTHOR]