The headspace sampler is a key component of a GC/MS system used to analyze ethanol and its metabolites in biological samples for NIAAA research. A single sequence run involves 80 samples and takes approximately 20 hours to complete. During this time, all samples remain in the sampler trays at room temperature, which can introduce bias between early and late samples. No budget amount or performance location is specified. No non-bid or submission timelines are provided.