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Updated: Jan 30, 2026

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
Published on: March 9, 2018
Characterization of DNPH-coated microreactor chip for analysis of trace carbonyls with application for breath
Yizheng Chen1, Qi Li1, Zhenzhen Xie1
1Department of Chemical Engineering, University of Louisville, Louisville, KY 40208, USA.
Abstract:
The analysis of trace carbonyls including aldehydes and ketones is important for monitoring environmental air quality, determining toxicity of aerosol of electronic cigarette, and detecting diseases by breath analysis. This work reports investigation of a single microreactor chip with HClO4-acidified DNPH coating for capture and analysis of carbonyls in air and exhaled breath. Three aldehydes and three ketones were spiked into one liter synthetic air in Tedlar bags serving as gaseous carbonyl standard for characterization of capture efficiency (CE). The HClO4-acidified DNPH showed higher CE of carbonyls than conventionally-used acid including H3PO4 and H2SO4 acidified DNPH under the microreactor conditions. The microreactor conditions including HClO4 to DNPH molar ratio, DNPH to carbonyls molar ratio, and gaseous sample flow rate through the microreactor were studied in detail and thereby optimized. Under the optimized conditions, 100% of CEs for aldehydes and above 80% for ketones were obtained. The microreactor chips were applied to determine acetone concentration in exhaled breath.
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