The analysis of linear and monomethylalkanes in exhaled breath samples by GC × GC-FID and GC–MS/MS

• INCAT device for sampling of hydrocarbons with wide range of volatility was developed.
• Comparison of GC × GC-FID and GC–MS/MS methods for exhaled breath analysis was performed.
• Determination of all C6C19n-alkanes and C9C19 monomethylalkanes in exhaled breath was performed.

A new arrangement of the INCAT (inside needle capillary adsorption trap) device with Carbopack X and Carboxen 1000 as sorbent materials was applied for sampling, preconcentration and injection of C6C19n-alkanes and their monomethyl analogs in exhaled breath samples. For the analysis both GC–MS/MS and GC × GC-FID techniques were used. Identification of the analytes was based on standards, measured retention indices and selective SRM transitions of the individual isomers. The GC–MS/MS detection limits were in the range from 2.1 pg for n-tetradecane to 86 pg for 5-methyloctadecane. The GC × GC-FID detection limits ranged from 19 pg for n-dodecane to 110 pg for 3-methyloctane.