Effect of using Propanol as internal standard on quantitative determination of ethanol in different biological matrices by head space-Gas Chromatography-Flame Ionization Detector

Identification and quantification of ethanol in biological samples such as blood and urine is of paramount importance in forensic toxicological laboratories. Despite of the fact that there are several methods are available for quantification of ethanol in forensic samples, an accurate quantification with minimum standard deviation is still a challenging task in forensic toxicological laboratories. Headspace Gas Chromatography-Flame Ionization Detection (HS-GC-FID) is a widely used analytical method for quantitative determination of ethanol. In the present work, we evaluate effect of using propanol as internal standard in different biological metrices on ethanol quantification. Results show that using propanol as internal standard relative standard deviations are significantly reduced and calibration curves were found linear with a correlation coefficient (R2) of 0.999. In conclusion, HS-GC-FID method was found to be fast, accurate, sensitive and robust for quantitative determination of ethanol in complex biological matrices e.g. blood and urine.