Relationship between the matrix effect and the physicochemical properties of analytes in gas chromatography
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The phenomenon “matrix-induced chromatographic response enhancement” (matrix effect) causes quantitative errors in gas chromatography (GC) analyses. This effect varies according to the analyte nature, matrix type and concentration, and GC-system parameters. By focusing on the physicochemical properties of analytes, a predictive model was developed for the matrix effect using quantitative structure–property relationships. Experimental values of the matrix effect were determined for 58 compounds in a serum extract obtained from solid-phase extraction as the matrix. Eight molecular descriptors were selected, and the matrix-effect model was developed by multiple linear regression. The developed model predicted values for the matrix effect without any further experimental measurements. It also indicated that the molecular polarity (particularly H-bond donors) and volume of the analyte increase the matrix effect, while hydrophobicity and increasing number of nonpolar carbon atoms in the analyte decrease the matrix effect. The model was applied to the analysis of barbiturates. The predicted values indicated that N-methylation decreases the matrix effect, and the relative predicted values were effective for the selection of an internal standard. The obtained insight into the matrix effect and the prediction data will be helpful for developing quantitative analysis strategies.
KeywordsMatrix effect Gas chromatography Quantitative structure–property relationship H-bond donor
This study was supported by the Japan Society for the Promotion of Science KAKENHI Grant Numbers 24590850, 24659338. The authors would like to thank Kohtaro Yuta (In Silico Data, Japan), Masato Kitajima, and Jose M. Ciloy (Fujitsu Kyushu Systems Ltd., Japan) for their helpful discussions and valuable comments on the manuscript.
- 1.Erney DR, Gillespie AM, Gilvydis DM, Poole CF (1993) Explanation of the matrix-induced chromatographic response enhancement of organophosphorus pesticides during open tubular column gas chromatography with splitless or hot on-column injection and flame photometric detection. J Chromatogr 638:57–63CrossRefGoogle Scholar
- 29.Liu RH, McKeehan AM, Edwards C, Foster G, Bensley WD, Langner JG, Walia AS (1994) Improved gas chromatography/mass spectrometry analysis of barbiturates in urine using centrifuge-based solid-phase extraction, methylation, with d5-pentobarbital as internal standard. J Forensic Sci 39:1504–1514Google Scholar