A compact breath acetone analyser based on an ultraviolet light emitting diode

A gas analyser for acetone based on measurement of the absorption of ultraviolet wavelengths near 285 nm in a compact multipass cell has been demonstrated. The analyser has a robust, compact and low-cost configuration which includes a light emitting diode (LED) light source, silicon photodiode light detection and does not require optical cavity enhancement. The analyser has been tested in various configurations for synthetic gas mixtures and breath samples from several human subjects. The analyser provides a lower limit of detection of 0.7 ppmv acetone, precision of 0.4 ppmv (3σ) and has worst-case residual errors of ±0.2 ppmv (up to 5 ppmv) and ±0.3 ppmv (up to 3.9 ppmv) for synthetic gas mixtures and human breath, respectively. These results indicate that this analyser concept has excellent potential to meet the requirements for making breath acetone measurements for lifestyle monitoring and medical screening applications.