Micro vapor extractor for on-site determinations of volatile organic compounds in water and biofluids

A passive, membrane-mediated, microfabricated vapor extractor (μVE) chip for collecting volatile organic compounds (VOC) from water and biofluids is presented. Its performance when interfaced to a micro-scale gas chromatograph (μGC) prototype is demonstrated. A mixture of 4 VOCs spiked into synthetic urine at ppm concentrations was extracted by the 2.8×2.3 cm μνΕ chip from a 700-μL sample in 3.5 min, and then preconcentrated, injected, separated and detected by μGC in ∼80 sec with detection limits as low as 660 ppb. Response patterns provided by the μGC sensor-array detector facilitated VOC identification. The hybrid μνΕ-μGC microsystem may eventually permit rapid field/clinical analyses of water contaminants and urinary biomarkers of exposure and disease.