he headspace sampler is a critical component of the gas chromatography/mass spectrometry (GC/MS) system, which is utilized for determining ethanol and its metabolites in biological samples. This process is integral to ongoing projects within the NIAAA intramural research program focusing on ethanol metabolism. The sampler functions by hosting samples in its trays and systematically introducing them into the GC/MS instrument. The GC/MS then acquires data for each sample according to a pre-scheduled sequence, processing samples one after another. Typically, a single sequence run involves 80 samples, requiring approximately 20 hours to complete. During this period, all 80 samples remain in the trays of the headspace sampler at room temperature. This prolonged exposure at room temperature can potentially introduce bias, particularly between samples run at the beginning and those processed at the end of the sequence.