The increasing use of neonicotinoids in systematic seed treatment to crops is a serious cause of pollution of water resources and environment. Consequently, food sources can get eventually contaminated. To this end, it is desirable to develop suitable and effective platforms in order to obtain low-cost and sensitive sensors for neonicotinoids detection. In this work, graphene oxide modified electrodes were used as highly efficient electrochemical sensors for detection of two common insecticides - thiamethoxam and imidacloprid. The proposed sensor responded linearly in the concentration range of 10-200µmolL(-1) for both analytes and the detection limits were determined as low as 8.3µmolL(-1) and 7.9µmolL(-1) for thiamethoxam and imidacloprid, respectively. Analytical performance was also evaluated on spiked water and honey samples.
- MeSH
- analýza potravin ekonomika metody MeSH
- biosenzitivní techniky ekonomika metody MeSH
- chemické látky znečišťující vodu analýza MeSH
- dusíkaté sloučeniny analýza MeSH
- elektrochemické techniky ekonomika metody MeSH
- elektrody MeSH
- grafit chemie MeSH
- imidazoly analýza MeSH
- insekticidy analýza MeSH
- kontaminace potravin analýza MeSH
- limita detekce MeSH
- med analýza MeSH
- monitorování životního prostředí ekonomika metody MeSH
- oxaziny analýza MeSH
- oxidy chemie MeSH
- řeky chemie MeSH
- thiazoly analýza MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
A fast, sensitive, and accurate GC/MS method for the quantification of aliphatic nitroesters (ethylene glycol dinitrate, nitroglycerin, and triethylene glycol dinitrate) and aromatic amines (diphenylamine, 2-nitrodiphenylamine, and triphenylamine) in propellants was developed and validated. This method comprises a Soxhlet extraction step with dichloromethane, followed by separation on a capillary column MDN-5. Ionization of the analytes is carried out using electron ionization. The limit of quantification of the method was 1% w/w for aliphatic nitroesters and 0.1% w/w for aromatic amines (diphenylamine and triphenylamine). Values of repeatability and reproducibility for analyzed compounds were smaller than values of the maximum allowed tolerances of the Horwitz-equation RSD(max) and 2/3 RSD(max). Values of accuracy for selected compounds were below the acceptable threshold of 15% for all tested levels in the range of calibration curve excepting the lowest concentration of calibration curve for nitroglycerin and aromatic amines. During the validation of method, temperature instability in injection port of gas chromatograph and column was observed for 2-nitrodiphenylamine. Hence, it follows worse results of accuracy and linearity and 2-nitrodiphenylamine was not validated successfully.
