Detection of acetone in exhaled breath by gold nanoparticle gas sensors
Zhenzhen Xiea, Xiao-an Fua*
a Department of Chemical Engineering, University of Louisville, Louisville, KY 40292
*Corresponding author: email@example.com
With the worldwide prevalence of diabetes, the methods for diagnosing have received considerable interest. The conventional method of blood tests is painful and has some limitations. Acetone in the human breath has been identified as an important biomarker for diagnosis of diabetes. The average concentration of exhaled acetone in the healthy human breath is found to be lower than 0.8 ppm, while that is higher than 1.8 ppm in diabetic patients. Gas sensors with sub-ppm acetone detection capacity play a significant role in the development of noninvasive monitors for diabetic patients. Gold nanoparticle-based sensors offer several advantages over conventional metal oxide-based sensors, including low power consumption, flexibility, ambient temperature operation and good chemical selectivity. They can be operated at room temperature and have shown limits of detection in the parts-per-million (ppm) or even parts-per-billion (ppb) level.
The main objective of this work is to increase the sensitivity of the sensors between different gold-thiolate nanoparticles for the detection of volatile organic compounds (VOCs) in human breath and dry air, and also the effect of the relative humidity. Gold nanoparticles with small size (< 5 nm) were synthesized. We found that the response follows a linear regression with increasing concentration of VOC in the range from 0.1 ppb to 5 ppm. Our results show that gas sensors based on gold nanoparticles could be used to distinguish healthy human from diabetic patients.
Keywords: diabetes, acetone, gold nanoparticle, sensors