Analyte protectants and matrix effects in GC
Soares, Lara Cristina T.; Santos Neto, Álvaro José
Palavras-chave: GC, gas chromatography, matrix effect, analyte protectants, troubleshooting, pesticides.
Resumo: Special attention has been paid about the deleterious effects caused by interferences from the sample matrix in liquid chromatography coupled to mass spectrometry. However, the occurrence of problems related to matrix effects is not exclusive from the above technique, also reaching the very traditional gas chromatography. In both cases, gas chromatography and high performance liquid chromatography, the problems have a common origin, the existence of matrix interferences from the extract to be analyzed. Nevertheless, its consequences are essentially different in the types of problems arising. Particularly for gas chromatography, problems are not regarded exclusively with its coupling to mass spectrometry, actually they can be observed with virtually all other detectors and being intrinsic or inherent to the chromatographic technique itself. In this article a brief but comprehensive discussion will be conducted about the effects that the matrix exerts on the gas chromatography. Furthermore, it will be discussed, in particular, the role that has been allocated for the so-called “analyte protectants”. These compounds are used in an attempt to mitigate the negative effects that the matrix plays in the application of methods in real situations; without, however, dismiss the favorable effects to the technique, conferred by the remaining compounds of the matrix in the final extract.
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