Online sample conditioning for portable breath analyzers

Authors
Prabhakar, Amlendu; Iglesias, Rodrigo Alejandro; Shan, Xiaonan; Xian, Xiaojun; Zhang, Lihua; Tsow, Francis; Forzani, Erica S.; Tao, Nongjian
Publication Year
2012
Language
English
Format
article
Status
Published version
Description
Various innovative chemical sensors have been developed in recent years to sense dangerous substances in air and trace biomarkers in breath. However, in order to solve real world problems, the sensors must be equipped with efficient sample conditioning that can, e.g., control the humidity, which is discussed much less in the literature. To meet the demand, a miniaturized mouthpiece was developed for personal breath analyzers. A key function of the mouthpiece is to condition the humidity in real breath samples without changing the analyte concentrations and introducing substantial backpressure, which is achieved with optimized packing of desiccant particles. Numerical simulations were carried out to determine the performance of the mouthpiece in terms of various controllable parameters, such as the size, density, and geometry of the packing. Mouthpieces with different configurations were built and tested, and the experimental data validated the simulation findings. A mouthpiece with optimized performance reducing relative humidity from 95% (27 000 ppmV) to 29% (8000 ppmV) whereas retaining 92% nitric oxide (50 ppbV to 46 ppbV) was built and integrated into a hand-held exhaled nitric oxide sensor, and the performance of exhaled nitric oxide measurement was in good agreement with the gold standard chemiluminescence technique. Acetone, carbon dioxide, oxygen, and ammonia samples were also measured after passing through the desiccant mouthpiece using commercial sensors to examine wide applicability of this breath conditioning approach. © 2012 American Chemical Society.
Fil: Prabhakar, Amlendu. Arizona State University; Estados Unidos
Fil: Iglesias, Rodrigo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Arizona State University; Estados Unidos
Fil: Shan, Xiaonan. Arizona State University; Estados Unidos
Fil: Xian, Xiaojun. Arizona State University; Estados Unidos
Fil: Zhang, Lihua. Arizona State University; Estados Unidos
Fil: Tsow, Francis. Arizona State University; Estados Unidos
Fil: Forzani, Erica S.. Arizona State University; Estados Unidos
Fil: Tao, Nongjian. Arizona State University; Estados Unidos
Subject
CHEMICAL SENSOR
SAMPLE PREPARATION
MOUTHPIECE
BREATH ANALYZER
Otras Ciencias Químicas
Ciencias Químicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/62481