Development of headspace SPME method for analysis of volatile organic compounds present in human biological specimens

In recent years, interest has increased regarding the identification of volatile organic compounds (VOCs) for metabolic profiling, human scent identification of the living and deceased, and diagnostic potentials for certain diseases that are known for its association with distinct odor. In this study, a method has been developed that is capable of sampling, identifying, and differentiating the VOCs present in various biological specimens of forensic importance (blood, breath, buccal cells, and urine) taken from the same individuals. The developed method requires a pretreatment step to remove targeted VOCs from the sampling apparatus prior to sampling of the individual specimens. The VOCs collected from the biological specimens were characterized by solid-phase microextraction and gas chromatography/mass spectrometry with ratios of the most abundant and frequent VOCs compared using qualitative and semiquantitative methods. Blood, breath, and buccal cells required extraction procedures ranging from 18 to 21 h in order to optimize the limit of detection, which averaged 5-15 ng across these specimens. The optimal method for measuring urine VOCs was complete in less than an hour; however, the limit of detection was higher with a range of 10-40 ng quantifiable. The demonstrated sensitivity and reproducibility of the methods developed allow for population studies of human scent VOCs from various biological specimen collection kits used in the forensic and clinical fields.