Acetone gas in exhaled breath and skin gas is produced when fatty acids are used as an energy source in the body. The selective and sensitive continuous measurement of acetone gas would be useful for the early screening of diabetes mellitus, a condition characterized by increased fatty acid metabolism. In particular, there is a growing need for acetone gas sensors that enable the wearable measurement of trace concentrations of acetone gas emitted through the skin. In this study, we improved the sensor’s sensitivity by optimizing the fluorescence measurement system and flow cell of a previously developed biofluorometric acetone gas sensor (bio-sniffer) using secondary alcohol dehydrogenase. To evaluate the performance of the improved acetone bio-sniffer, we constructed a dilution system to prepare acetone gas at subparts per billion by volume (ppbv) levels and verified its accuracy using gas chromatography–mass spectrometry. As a result, the dilution system was able to prepare 0.1 ppbv of acetone gas with a coefficient of variation of 5%. The improved acetone bio-sniffer demonstrated quantitative characteristics in the concentration range of 0.5–1000 ppbv, with a lower limit of quantification that was 40 times better than that of the conventional acetone bio-sniffer. In the future, this system is expected to be used for continuous measurement of acetone gas released through the skin.

中文翻译：

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亚 ppbv 级灵敏度的生物荧光丙酮气体传感器


呼出气中的丙酮气体和皮肤气体是在脂肪酸用作体内能量来源时产生的。选择性和灵敏的丙酮气体连续测量将有助于糖尿病的早期筛查，糖尿病是一种以脂肪酸代谢增加为特征的疾病。特别是，对丙酮气体传感器的需求不断增长，这些传感器能够对皮肤排放的痕量浓度的丙酮气体进行可穿戴测量。在这项研究中，我们通过使用二次醇脱氢酶优化先前开发的生物荧光丙酮气体传感器 （bio-sniffer） 的荧光测量系统和流通池来提高传感器的灵敏度。为了评估改进的丙酮生物嗅探器的性能，我们构建了一个稀释系统来制备十亿分之一体积 （ppbv） 水平的丙酮气体，并使用气相色谱-质谱法验证了其准确性。结果，稀释系统能够制备 0.1 ppbv 的丙酮气体，变异系数为 5%。改进的丙酮生物嗅探器在 0.5–1000 ppbv 的浓度范围内表现出定量特性，定量下限比传统丙酮生物嗅探器高 40 倍。未来，该系统有望用于连续测量通过皮肤释放的丙酮气体。