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Determination of chloramphenicol in milk powder using liquid-liquid cartridge extraction (Chem Elut) and liquid chromatography-tandem mass spectrometry

100%
Zawadzka I., Rodziewicz L.
Roczniki Państwowego Zakładu Higieny
|
2014
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tom 65
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nr 3
Background. The European Union prohibits the use of chloramphenicol (CAP) as a veterinary drug in food-producing animals. Nevertheless, CAP have been detected in milk products (liquid milk and milk powder). Therefore, it is necessary to develop sensitive methods for determining CAP residues in milk powder. Objective. The aim of this study was to develop and validate a confirmatory method for determination of CAP in milk powder. Material and methods. Chloramphenicol was determined in milk powder using LC-ESI-MS/MS in negative mode. After fat removing milk powder sample was extracted/cleaned-up with a Chem Elut extraction cartridge. Separation was achieved on a Phenomenex Luna C-18 column with acetonitrile-water as a mobile phase. The mass spectrometer was operated in multiple reaction monitoring mode (MRM). Four transitions were monitored m/z 321→152, 321→194, 321→257 (CAP) and 326→157 (IS CAP-d5). Results. Linearity, accuracy, precision, decision limit (CCa), detection capability (CCb) and ruggedness were determined for m/z 321→152. The mean relative recoveries (inter standard-corrected) of CAP from whole milk powder spiked at levels 0.1, 0.2, 0.3 and 0.6 mg/kg were in the range 95 - 103%. Relative standard deviation (RSD%) of recoveries at all spiked levels were less than 14%. RSDs within-laboratory reproducibility calculated at fortification of 0.3 mg/kg was less than 16%. CCa and CCb were below 0.1 mg/kg. Conclusions. The developed LC-MS/MS method allows the determination of CAP in milk powder. The method was validated according to the Commission Decision No. 2002/657/EC requirements. This method can be applied to determination CAP in whole and skim milk powder.
2

Influence of geosmin, dimethyl trisulfide, 2- and 3-methylbutan-1-ol on raw spirits quality

84%
Biernacka P., Plutowska B., Wardencki W.
Nauka Przyroda Technologie. Uniwersytet Przyrodniczy w Poznaniu
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2009
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tom 03
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nr 4
3

U-HPLC-MS/MS analysis to quantify the antioxidant content of tomatoes subjected to different cultivation conditions

84%
Van Meulebroek L., Vanhaecke L., De Swaef T., Steppe K., De Brabander H.
Polish Journal of Food and Nutrition Sciences
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2011
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tom 61
|
nr Suppl.1
4

Comparison of extraction techniques by matrix solid phase dispersion and liquid-liquid for screening 150 pesticides from soil, and determination by gas chromatography

84%
Lozowicka B., Jankowska M., Rutkowska E., Kaczynski P., Hrynko I.
Polish Journal of Environmental Studies
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2012
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tom 21
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nr 4
Interest in the determination and screening of pesticide residues in soil is caused by widespread use of chemical pesticides in agriculture, which increase soil contamination. Two extraction techniques, matrix solid phase dispersion (MSPD) and liquid-liquid extraction (LLE) of residual pesticides (acaricides, insecticides, herbicides, and fungicides) from soil were compared. Advantages and disadvantages of both approaches were discussed. Pesticides from different chemical classes (organohalogen, organophosphorus, carbamates, pyrethroids, strobilurines, triazoles) were quantified by GC with a dual system detection - electron capture (EC) and/or nitrogen-phosphorus (NP). The MSPD was validated by comparing it with conventional LLE. Recovery studies were carried out at three levels: 1) ranged between 0.005-0.05 mg/kg, 2) 0.05-0.5 mg/kg, and 3) 0.25-2.5 mg/kg and average recoveries obtained for these compounds ranged from 72.4 to 120% for MSPD and 70.6-120% for LLE with relative standard deviations (RSDs) below 20%. Both methods were linear over the range assayed, 0.005-2.5 mg/kg. The uncertainties of the analytical methods were lower than 25.6% and 30%, with and without recovery correction, respectively. The rapid and practical MSPD technique has found a particular application in determining 147 pesticide residues of different physicochemical properties in soil with satisfactory validation parameters. The study estimated that MSPD has significant advantages over LLE because, coupled with simultaneous stage of purification, it allowed for a radical reduction time of analysis and its cost. MSPD fulfilled the requirements of multiresidue techniques. The method is reliable and can be useful for routine monitoring in soil.
5

Application of high performance liquid chromatography with UV and tandem MS detection for analysis of beta-carotene in food supplement based on conifer needle extract

84%
Rjabova J., Bartkevics V., Drille M., Rubens J.
Polish Journal of Food and Nutrition Sciences
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2011
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tom 61
|
nr Suppl.1
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