A microfluidic lab-on-chip derivatisation technique for the measurement of gas phase formaldehyde

摘要: A microfluidic lab-on-chip derivatisation technique has been optimized to achieve a rapid, automated and sensitive determination of ambient gaseous formaldehyde when used in combination with GC-MS. The method Pyrex micro-reactor comprising three inlets one outlet, gas fluid splitting combining channels, mixing junctions, 2.0 m long, 620 μm internal diameter reaction micro-channel. integrated functions, that of: (1) mixer reactor, (2) heater, (3) preconcentrator. flow rates the sample solution temperature were near real-time measurement rapid high efficiency step following sampling. enhanced phase contact area-to-volume ratio heat transfer rate resulted fast reaction. Calibration showed good linearity range 26 331 ppb correlation coefficients R2 = 0.988 0.997 for PFPH PFBHA derivatives. For low ratios (<26 ppb) could be repeatedly recycled through chip enabling pre-concentration derivative – hydrazone. calibration curves this recycling approach also from 4.0 detection limits (MDLs) 2.1 1.1 feasibility was assessed using measurements laboratory air, predominant carbonyl compound at 12.5 level. proof principle experiments demonstrated potential on-line other carbonyls including acetaldehyde, acetone propionaldehyde.