Selective low concentration ammonia sensing in a microfluidic lab-on-a-chip


Timmer, Björn H. and Delft, Koen M. van and Koelmans, W.W. and Olthuis, Wouter and Berg, Albert van den (2006) Selective low concentration ammonia sensing in a microfluidic lab-on-a-chip. IEEE Sensors Journal, 6 (3). pp. 829-835. ISSN 1530-437X

open access
Abstract:In the medical community, there is a considerable interest in a diagnostic breath analyzer for ammonia that is selectively enough to measure in exhaled air and small enough for the small volumes available in such an application. An indirect measurement system for low gaseous ammonia concentrations has been miniaturized and integrated on a chip in order to reach this goal. The detection limit of the system was calculated to be 1.1 parts per billion (ppb). The response time was determined to be 1.6 min with a gas How of 50 ml/min. The required gas volume for one measurement is therefore sufficiently small, although sampling assistance is required for breath analysis. The selectivity of the system is sufficient to measure ammonia concentrations in the low-ppb range. The system is even sufficiently selective to be used in environments that contain elevated carbon dioxide levels, like exhaled air. The lower ammonia concentration expected in diagnostic breath analysis applications, 50 ppb, was demonstrated to be detectable.
Item Type:Article
Copyright:© 2006 IEEE Press
Electrical Engineering, Mathematics and Computer Science (EEMCS)
Research Group:
Link to this item:
Official URL:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page

Metis ID: 231955