PPB level gas quantification by bubble chromatography

This paper reports the part-per-billion (ppb) level quantification capability of a bubble gas chromatography technique. Previously we reported the concept and operation principle of a bubble chromatography that identified different gas types by monitoring bubble diameters of different gases. One unique capability of the bubble chromatography is the capture of a gas into multiple bubbles, thus potentially enabling quantification by counting the number of bubbles. This paper first time reports such a quantifying capability down to 26.9 ppb in a linear response range between 2.09 pL and 1.00 μL. The microfluidic device generated 400 bubbles/second and enabled measurement down to 0.84 nL pentane/second with an increment of only 2.09pL/bubble resolution.