Quantitative analysis with headspace sampling of solid matrices is a complex task. Their quantitative composition can be determined on the matrix either as such or suspended in a non-volatile liquid. In general, the latter approach is preferred because it affords the internal standard to be homogeneously included and sensitivity to be increased for analytes poorly soluble in the suspension medium. The suspension mode can produce artefacts making indispensable to analyze the matrix as such, thus affecting a correct quantitation because of the lack of internal standard repeatability. Multiple headspace extraction is a quantitative approach enabling the matrix effect to be eliminated developed [1] recently applied to HS-SPME [2,3]. It is based on a stepwise dynamic gas extraction. The analyte peak area decays exponentially with the number of extractions affording to measure the total area from the first extraction through the slope Q of the analyte exponential decay. In this study MHS-SPME was used to quantify some markers of a group of spices. The results showed a constant Q value within a relatively homogeneous set of samples, thus making it possible to quantify marker(s) of a sample in a single analysis. The possibility to combine HS-SPME and mass spectrometry while avoiding GC separation was also investigated.
QUANTITATIVE ANALYSIS OF VEGETABLE SOLID MATRICES BY MULTIPLE HEADSPACE SOLID PHASE MICROEXTRACTION: DETERMINATION OF BIOLOGICALLY ACTIVE COMPOUNDS IN SPICES
RUOSI, MANUELA ROSANNA;BICCHI, Carlo;CAGLIERO, Cecilia Lucia;CORDERO, Chiara Emilia Irma;GRIGLIONE, Alessandra;LIBERTO, Erica;RUBIOLO, Patrizia;SGORBINI, Barbara
2012-01-01
Abstract
Quantitative analysis with headspace sampling of solid matrices is a complex task. Their quantitative composition can be determined on the matrix either as such or suspended in a non-volatile liquid. In general, the latter approach is preferred because it affords the internal standard to be homogeneously included and sensitivity to be increased for analytes poorly soluble in the suspension medium. The suspension mode can produce artefacts making indispensable to analyze the matrix as such, thus affecting a correct quantitation because of the lack of internal standard repeatability. Multiple headspace extraction is a quantitative approach enabling the matrix effect to be eliminated developed [1] recently applied to HS-SPME [2,3]. It is based on a stepwise dynamic gas extraction. The analyte peak area decays exponentially with the number of extractions affording to measure the total area from the first extraction through the slope Q of the analyte exponential decay. In this study MHS-SPME was used to quantify some markers of a group of spices. The results showed a constant Q value within a relatively homogeneous set of samples, thus making it possible to quantify marker(s) of a sample in a single analysis. The possibility to combine HS-SPME and mass spectrometry while avoiding GC separation was also investigated.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.