Details

Autor(en) / Beteiligte

• Righettoni, Marco
• Tricoli, Antonio
• Pratsinis, Sotiris E

Titel

Si:WO3 Sensors for Highly Selective Detection of Acetone for Easy Diagnosis of Diabetes by Breath Analysis

Ist Teil von

• Analytical chemistry (Washington), 2010-05, Vol.82 (9), p.3581-3587

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

2010

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Acetone in the human breath is an important marker for noninvasive diagnosis of diabetes. Here, novel chemo-resistive detectors have been developed that allow rapid measurement of ultralow acetone concentrations (down to 20 ppb) with high signal-to-noise ratio in ideal (dry air) and realistic (up to 90% RH) conditions. The detector films consist of (highly sensitive) pure and Si-doped WO3 nanoparticles (10−13 nm in diameter) made in the gas phase and directly deposited onto interdigitated electrodes. Their sensing properties (selectivity, limit of detection, response, and recovery times) have been investigated as a function of operating temperature (325−500 °C), relative humidity (RH), and interfering analyte (ethanol or water vapor) concentration. It was found that Si-doping increases and stabilizes the acetone-selective ε-WO3 phase while increasing its thermal stability and, thus, results in superior sensing performance with an optimum at about 10 mol % Si content. Furthermore, increasing the operation temperature decreased the detector response to water vapor, and above 400 °C, it was (≤0.7) always below the threshold (10.6) for fake diabetes detection in ideal conditions. At this temperature and at 90% RH, healthy humans (≤900 ppb acetone) and diabetes patients (≥1800 ppb) can be clearly distinguished by a remarkable gap (40%) in sensor response. As a result, these solid state detectors may offer a portable and cost-effective alternative to more bulky systems for noninvasive diabetes detection by human breath analysis.