Breath Acetone Research Articles

A fully integrated standalone portable cavity ringdown breath acetone analyzer.

Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

Dielectric barrier discharge micro-plasma emission spectrometry for the detection of acetone in exhaled breath

Acetone is a predominant volatile organic compound (VOC) in the exhaled breath and a promising biomarker for diabetes and ketoacidosis. A non-thermal micro-plasma generated in a planar dielectric barrier discharge (DBD) is used as a radiation source for the excitation of gaseous acetone followed by its quantification with optical emission spectrometry (OES). Gaseous acetone can be directly sampled, while liquid acetone is evaporated by heated tungsten coil and then introduced into the DBD micro-plasma by a helium carrier flow for performing optical emission and detection at a 519nm emission line. In the present study, the exhaled breath is collected and transferred into aqueous medium for sampling. With a sampling volume of 7μL in a micro-drop, a linear range of 40–1600mgL−1 is obtained along with a detection limit of 44ng and a precision of 5.7% RSD. The present system is successfully applied to the determination of breath acetone for both diabetic patients and healthy volunteers.

Preparation and Gas Sensing Properties of In2O3/Au Nanorods for Detection of Volatile Organic Compounds in Exhaled Breath.

A series of In2O3/Au nanorods (NRs) were fabricated and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X–ray diffractometer (XRD) and X–ray photoelectron spectroscopy (XPS). The length to diameter ratios of In2O3/Au NRs was periodically modulated in the range of 2.9–4.5 through controlling the initial content of indium salt and reaction time. Their gas sensing properties to volatile organic compounds (VOCs) were carefully studied and then applied in exhaled breath detection. The results demonstrate that In2O3/Au NRs gas sensor can effectively detect acetone at 250 °C and ethanol at 400 °C. The corresponding actual detection limit is as low as 0.1 ppm to acetone and 0.05 ppm to ethanol, respectively. Moreover, by using humidity compensation method, In2O3/Au NRs gas sensor can clearly distinguish the acetone and ethanol biomarkers in human breath. The main reason of the enhanced gas sensing properties was attributed to the “spillover effects” between Au and In2O3 NRs. The excellent sensing performance indicates that In2O3/Au NRs is a promising functional material to actual application in monitoring and detecting diabetes and safe driving area in a noninvasive and more accurate way.

An acetone bio-sniffer (gas phase biosensor) enabling assessment of lipid metabolism from exhaled breath.

Several volatile organic compounds (VOCs) are released from human breath or skin. Like chemical substances in blood or urine, some of these vapors can provide valuable information regarding the state of the human body. A highly sensitive acetone biochemical gas sensor (bio-sniffer) was developed and used to measure exhaled breath acetone concentration, and assess lipid metabolism based on breath acetone analysis. A fiber-optic biochemical gas sensing system was constructed by attaching a flow-cell with nicotinamide adenine dinucleotide (NADH)-dependent secondary alcohol dehydrogenase (S-ADH) immobilized membrane onto a fiber-optic NADH measurement system. The NADH measurement system utilizes an ultraviolet-light emitting diode with peak emission of 335 nm as an excitation light source. NADH is consumed by the enzymatic reaction of S-ADH, and the consumption is proportional to the concentration of acetone vapor. Phosphate buffer which contained NADH was circulated into the flow-cell to rinse products and the excessive substrates from the optode. The change of fluorescent emitted from NADH is analyzed by the PMT. Hence, fluorescence intensity decreased as the acetone concentration increased. The relationship between fluorescence intensity and acetone concentration was identified from 20 ppb to 5300 ppb. This interval included the concentration of acetone vapor in the breath of healthy people and those suffering from disorders of carbohydrate metabolism. Finally, the acetone bio-sniffer was used to measure breath acetone during an exercise stress test on an ergometer after a period of fasting. The concentration of acetone in breath was shown to significantly increase after exercise. This biosensor allows rapid, highly sensitive and selective measurement of lipid metabolism.

A cross-sectional study of breath acetone based on diabetic metabolic disorders

Breath acetone is a known biomarker for diabetes mellitus in breath analysis. In this work, a cross-sectional study of breath acetone based on clinical metabolic disorders of type 2 diabetes mellitus (T2DM) was carried out. Breath acetone concentrations of 113 T2DM patients and 56 apparently healthy individuals were measured at a single time point. Concentrations varied from 0.22 to 9.41 ppmv (mean 1.75 ppmv) for T2DM, which were significantly higher than those for normal controls (ranged from 0.32 to 1.96 ppmv, mean 0.72 ppmv, p = 0.008). Observations in our work revealed that breath acetone concentrations elevated to different degrees, along with the abnormality of blood glucose, glycated hemoglobin (HbA1c), triglyceride and cholesterol. Breath acetone showed obviously positive correlations with blood ketone and urine ketone. Possible metabolic relations between breath acetone and diabetic disorders were also discussed. This work aimed at giving an overall assessment of breath acetone from the perspective of clinical parameters for type 2 diabetes.

Determination of breath acetone in 149 type 2 diabetic patients using a ringdown breath-acetone analyzer.

Over 90% of diabetic patients have Type 2 diabetes. Although an elevated mean breath acetone concentration has been found to exist in Type 1 diabetes (T1D), information on breath acetone in Type 2 diabetes (T2D) has yet to be obtained. In this study, we first used gas chromatography-mass spectrometry (GC-MS) to validate a ringdown breath-acetone analyzer based on the cavity-ringdown-spectroscopy technique, through comparing breath acetone concentrations in the range 0.5-2.5 ppm measured using both methods. The linear fitting of R = 0.99 suggests that the acetone concentrations obtained using both methods are consistent with a largest standard deviation of ±0.4 ppm in the lowest concentration of the range. Next, 620 breath samples from 149 T2D patients and 42 healthy subjects were collected and tested using the breath analyzer. Four breath samples were taken from each subject under each of four different conditions: fasting, 2 h post-breakfast, 2 h post-lunch, and 2 h post-dinner. Simultaneous blood glucose levels were also measured using a standard diabetic-management blood-glucose meter. For the 149 T2D subjects, their exhaled breath acetone concentrations ranged from 0.1 to 19.8 ppm; four different ranges of breath acetone concentration, 0.1-19.8, 0.1-7.1, 0.1-6.3, and 0.1-9.5 ppm, were obtained for the subjects under the four different conditions, respectively. For the 42 healthy subjects, their breath acetone concentration ranged from 0.1 to 2.6 ppm; four different ranges of breath acetone concentration, 0.3-2.6, 0.1-2.6, 0.1-1.7, and 0.3-1.6 ppm, were obtained for the four different conditions. The mean breath acetone concentration of the 149 T2D subjects was determined to be 1.5 ± 1.5 ppm, which was 1.5 times that of 1.0 ± 0.6 ppm for the 42 healthy subjects. No correlation was found between the breath acetone concentration and the blood glucose level of the T2D subjects and the healthy volunteers. This study using a relatively large number of subjects provides new data regarding breath acetone in diabetes (T1D and T2D) and suggests that an elevated mean breath acetone concentration also exists in T2D.

Microsystem in LTCC Technology to the Detection of Acetone in Exhaled Breath

lesser extent from enzymatic conversion of acetoacetate to acetone (18). The exhaled acetone is usually in the range of 0.3 - 0.9 ppm for healthy people, and over 3.0 ppm for people with diabetes (19). Acetone and other volatiles in breath are present in nanomolar quantities. In order to measure such low concentrations the laboratory systems are applied. They can be divided into two groups: on-line methods, i.e. proton transfer reaction mass spectrometry (PTR-MS) (20), atmospheric pressure chemical ionization mass spectrometry (APCI-MS) (21) and off-line methods such as: gas chromatography - mass spectrometry (GC-MS) (22), selected ion flow tube mass spectrometry (SIFT-MS) (23) based on sample preconcentration. Those methods are in fact very expensive and required a well qualified personnel, therefore their use is exclusively restricted to the laboratories. Based on literature review, exhaled breath acetone measurement in its developmental stage is currently characterized by intensive studies and creation of experimental prototype devices (24)-(26). In this paper the microsystem based on micropreconcentrator and gas sensors array manufactured in LTCC technology is presented.

Breath Acetone-Based Non-Invasive Detection of Blood Glucose Levels

Abstract There has been a constant demand for the development of non-invasive, sensitive glucose sensor system that offers fast and real-time electronic readout of blood glucose levels. In this article, we propose a new system for detecting blood glucose levels by estimating the concentration of acetone in the exhaled breath. A TGS822 tin oxide (SnO2) sensor has been used to detect the concentration of acetone in the exhaled air. Acetone in exhaled breath showed a correlation with the blood glucose levels. Effects of pressure, temperature and humidity have been considered. Artificial Neural Network (ANN) has been used to extract features from the output waveform of the sensors. The system has been trained and tested with patient data in the blood glucose ranges from 80 mg/dl to 180 mg/dl. Using the proposed system, the blood glucose concentration has been estimated within an error limit of ±7.5 mg/dl.

Study of breath acetone and its correlations with blood glucose and blood beta-hydroxybutyrate using an animal model with lab-developed type 1 diabetic rats

We report for the first time a study of breath acetone and its correlations with blood glucose (BG) and blood β-hydroxybutyrate (BHB) using an animal model of rats.

Facile synthesis of hierarchical porous WO3 nanofibers having 1D nanoneedles and their functionalization with non-oxidized graphene flakes for selective detection of acetone molecules

Hierarchical and porous one-dimensional (1D) nonwoven WO3 nanofibers were synthesized by electrospinning and controlled two-step heat-treatment, and are applicable for diabetes diagnostic sensors by selective detection of breath acetone.

Comparison of breath gases, including acetone, with blood glucose and blood ketones in children and adolescents with type 1 diabetes

Previous studies have suggested that breath gases may be related to simultaneous blood glucose and blood ketone levels in adults with type 2 and type 1 diabetes. The aims of this study were to investigate these relationships in children and young people with type 1 diabetes in order to assess the efficacy of a simple breath test as a non-invasive means of diabetes management. Gases were collected in breath bags and measurements were compared with capillary blood glucose and ketone levels taken at the same time on a single visit to a routine hospital clinic in 113 subjects (59 male, age 7 years 11 months–18 years 3 months) with type 1 diabetes. The patients were well-controlled with relatively low concentrations of the blood ketone measured (β hydroxybutyrate, 0–0.4 mmol l−1). Breath acetone levels were found to increase with blood β hydroxybutyrate levels and a significant relationship was found between the two (Spearman’s rank correlation ρ = 0.364, p < 10−4). A weak positive relationship was found between blood glucose and breath acetone (ρ = 0.16, p = 0.1), but led to the conclusion that single breath measurements of acetone do not provide a good measure of blood glucose levels in this cohort. This result suggests a potential to develop breath gas analysis to provide an alternative to blood testing for ketone measurement, for example to assist with the management of type 1 diabetes.

Analysis of ketone bodies in exhaled breath and blood of ten healthy Japanese at OGTT using a portable gas chromatograph

Ketone bodies including acetone are disease biomarkers for diabetes that sometimes causes severe ketoacidosis. The present study was undertaken to clarify the significance of exhaled acetone and plasma ketone bodies at bedside in a clinical setting. The oral glucose tolerance test (OGTT) was performed in 10 healthy Japanese volunteers (five females and five males). Exhaled breath acetone and volatile sulfide compounds (VSCs) in mouth air were measured simultaneously with blood sampling during the OGTT using a portable gas chromatograph equipped with an In2O3 thick-film type gas sensor and a VSC monitor. Acetone, β-hydroxybutyrate (β-OHB) and acetoacetate (AcAc) in blood plasma as well as glucose and insulin were examined. Oral conditions were examined based on the Community Periodontal Index (CPI) by one dentist. In addition, the same type of analysis was applied to two uncontrolled type 2 diabetes mellitus patients hospitalized at Tohoku University Hospital. Exhaled acetone was measured at the same time as blood withdrawal in the morning before breakfast and at night before bed at the beginning, the middle, and the end of hospitalization. All volunteers showed normal OGTT patterns with no ketonuria and periodontitis; however, there were significant correlations between breath acetone and plasma β-ΟΗΒ and between breath acetone and plasma AcAc under fasting conditions. Breath acetone of the type 2 diabetes mellitus patients showed positive correlations with plasma glucose when the level of plasma glucose tended to decrease during hospitalization. In spite of a very limited number of cases, our results support the idea that exhaled breath acetone may be related to plasma β-OHB and AcAc, which reflect glucose metabolism in the body.

Design and Analysis of Multilayer Semiconductor Sensor for Acetone Gas Sensing

Portable breath acetone sensor has great potential in diabetes diagnosis for acetone is a selective breath maker for diabetes. In this paper, we propose a multilayer semiconductor sensor for acetone gas sensing. Device is designed with stress adjustment layer, support layer, metal layer, insulator and sensing film. Simulation is performed, electrothermal and thermomechanical analyses demonstrate that this device has good performance in power consumption and thermomechanical reliability.

Breath Acetone as Biomarker for Lipid Oxidation and Early Ketone Detection

Former ketone studies, including ketoacidosis (KAD), fasting ketosis (FK), nutritional ketosis (NK), and exercis-eaffected ketosis have brought great advances to the field of ketones. In the present work, blood, urine and breath ketone detections were evaluated systematically. We found that breath ketone (acetone) is the ketone of choice for detecting early stages of ketosis. In addition, acetone was correlated with respiratory quotient, and found to be a highly sensitive non-invasive biomarker of lipid oxidation. Furthermore, acetone was used for fast screening of ketosis or ketoacidosis in populations, and demonstrated value upon screening a population of 48 individuals, among which a type I diabetes case with early symptoms of KAD and FK case were identified.

Comparison of breath acetone, with blood glucose and blood ketones in children and adolescents with type 1 diabetes

Comparison of breath acetone, with blood glucose and blood ketones in children and adolescents with type 1 diabetes

Micropreconcentrator in LTCC Technology with Mass Spectrometry for the Detection of Acetone in Healthy and Type-1 Diabetes Mellitus Patient Breath.

Breath analysis has long been recognized as a potentially attractive method for the diagnosis of several diseases. The main advantage over other diagnostic methods such as blood or urine analysis is that breath analysis is fully non-invasive, comfortable for patients and breath samples can be easily obtained. One possible future application of breath analysis may be the diagnosing and monitoring of diabetes. It is, therefore, essential, to firstly determine a relationship between exhaled biomarker concentration and glucose in blood as well as to compare the results with the results obtained from non-diabetic subjects. Concentrations of molecules which are biomarkers of diseases’ states, or early indicators of disease should be well documented, i.e., the variations of abnormal concentrations of breath biomarkers with age, gender and ethnic issues need to be verified. Furthermore, based on performed measurements it is rather obvious that analysis of exhaled acetone as a single biomarker of diabetes is unrealistic. In this paper, the author presents results of his research conducted on samples of breath gas from eleven healthy volunteers (HV) and fourteen type-1 diabetic patients (T1DM) which were collected in 1-l SKC breath bags. The exhaled acetone concentration was measured using mass spectrometry (HPR-20 QIC, Hiden Analytical, Warrington, UK) coupled with a micropreconcentrator in LTCC (Low Temperature Cofired Ceramic). However, as according to recent studies the level of acetone varies to a significant extent for each blood glucose concentration of single individuals, a direct and absolute relationship between blood glucose and acetone has not been proved. Nevertheless, basing on the research results acetone in diabetic breath was found to be higher than 1.11 ppmv, while its average concentration in normal breath was lower than 0.83 ppmv.

Breath metabolite response to major upper gastrointestinal surgery

BackgroundEsophagectomy and gastrectomy are associated with profound metabolic changes and significant postoperative morbidity. The aim of this prospective clinical study was to determine whether breath analysis can offer novel insight into the surgical metabolic response and identify biomarkers of postoperative complications, including lung injury. MethodsBreath samples were collected preoperatively and at 24, 48, 72, 96 and 168 h after esophagectomy (n = 25) and gastrectomy (n = 15). Targeted analysis of four prominent breath metabolites was performed by selected ion flow-tube mass spectrometry. Patients with nonsurgical lung injury (community-acquired pneumonia) were recruited as positive controls. ResultsPerioperative starvation and subsequent reintroduction of nutritional input were associated with significant changes in breath acetone levels. Breath acetone levels fell after esophagectomy (P = 0.008) and were significantly lower than in gastrectomy patients at postoperative time points 48 (P < 0.001) and 72 h (P < 0.001). In contrast, concentrations of isoprene increased significantly after esophagectomy (P = 0.014). Pneumonia was the most frequently observed postoperative complication (esophagectomy 36% and gastrectomy 7%). The concentration of hydrogen cyanide was significantly lower in the breath of patients who developed pneumonia, 72 h after surgery (P = 0.008). Exhaled hydrogen cyanide (P = 0.001) and isoprene (P = 0.014) were also reduced in patients with community-acquired pneumonia compared with healthy controls. ConclusionsSelected ion flow-tube mass spectrometry can be used as a totally noninvasive resource to monitor multiple aspects of metabolic alterations in the postoperative period. Exhaled concentrations of several prominent metabolites are significantly altered after major upper gastrointestinal surgery and in response to pneumonia.

Highly sensitive carbon nanotubes–SnO2 nanocomposite sensor for acetone detection in diabetes mellitus breath

Multiwall carbon nanotubes (MWCNTs)/SnO2 nanocomposites were synthesized by ultrasonic-assisted deposition–precipitation method and used for detection of acetone in the same range of concentrations as in diabetes mellitus breath. The nanocomposite samples were characterized by BET, FE-SEM, XRD and TEM. MWCNTs with an average size of about 60nm are coated with and uniformly dispersed in 5–10nm SnO2 nanoparticles matrix. To diagnose diabetes, the sensors responses to ppm concentrations of acetone were measured in a flow system at various temperatures and 85% relative humidity. Addition of MWCNTs dramatically enhances the sensors response to acetone. Moreover, the sensors response to ethanol, as an interfering species with acetone in human breath, was also measured. Breath humidity increases the conductivity of the sensing materials and therefore, lowers the sensors response to acetone.

Notions of Magnetoelectrocatalysis

Greater efficiency in reactions important to energy generation and storage has broad consequences beyond chemistry. Means to enhance reaction rates are typically by chemical manipulation of catalyst materials, but physical manipulation of reactions, as by temperature and pressure, is also effective. Here, means to increase reaction rates with magnetic fields and based on the magnetic properties of substrates and materials is considered.For a wide range of reactions and device relevant to electrochemical energy and power, introduction of magnetic microparticles onto or into an electrode structure has been found to increase rates and to reduce the tax of overpotential1-18. This includes batteries3-6, fuel cells7-11, photoelectrochemical cells1, dye sensitized solar cells13, asymmetric supercapacitors13, hydride storage15, and alcohol electrolysis13,14. Relevant reactions include hydrogen evolution reaction (HER)1, hydride storage15, and CO oxidation8.The basic notion is that electrons have properties of mass, charge, and spin. Spin interacts with the applied magnetic fields. To transfer an electron, it is necessary to transfer the spin and the charge. Application of a magnetic field should impact the rates of electron transfer. Experiments1-17 have shown that the rate of the reaction depends on the magnetic properties of the reactants and products as well as the strength of the applied magnetic field H or intensity B. Measured rates are highly correlated2 with the Zeeman energies in the system, Z = gSBb.Detailed temperature studies for academically interested redox probes has allowed development of a model for magnetic effects on self exchange reactions1. The model modifies Marcus theory to allow split of the energy levels by the applied field, which has several impacts on rate. The only specific chemical information in Marcus theory is the size and charge of the redox probe and the dielectric constant of the medium. Consideration of the magnetic effects introduces additional magnetic properties into the model.Here, several important energy relevant reactions are considered in light of the model. This includes the HER on several electrodes1, hydride storage in Pd15, and diffusion limited CO oxidation on Pt8. The impacts of the magnetic properties of the reactants and environment are discussed.ReferencesLee, H. C. Magnetic Field Effects on Photoelectrochemical Hydrogen Evolution, Heterogeneous and Self Exchange Reactions. Ph.D., University of Iowa (2011).Minteer, S. D. Magnetic Field Effects on Electron Transfer Reactions. Ph.D., University of Iowa (2000).Zou, P. & Leddy, J. Electrochemical and Solid-State Letters 9, A43-A45 (2006).Zou, P. Magnetic Field Effects on Nickel Electrodes for Nickel Metal Hydride Batteries. M.S., University of Iowa (2002).Tesene, J. P. Magnetically-Treated Electrolytic Manganese Dioxide in Alkaline Electrolyte. M.S., University of Iowa (2005).Motsegood, P. N. Improved Performance of Alkaline Batteries via Magnetic Modification and Voltammetric Detection of Breath Acetone at Platinum Electrodes. Ph.D., University of Iowa (2012).Dunwoody, D. C., Ünlü, M., Wolf, A. K. H., Gellett, W.L. & Leddy, J. Electroanalysis 17, 1487-1494 (2005).Gellett, W. L. Magnetic Microparticles on Electrodes: Polymer Electrolyte Membrane Fuel Cells, Carbon Monoxide Oxidation, and Transition Metal Complex Electrochemistry. Ph.D., University of Iowa (2004).Dunwoody, D. C. Magnetically Modified Polymer Electrolyte Fuel Cells and Low Temperature Effects on Polymer Electrolyte Nafion. Ph.D., University of Iowa (2003).Haverhals, L. Fuel Cells as Power Source and Sensors. Ph.D., University of Iowa (2008).Ünlü, M. Coated Magnetic Particles in Electrochemical Systems: Synthesis, Modified Electrodes, Alkaline Batteries and Paste Electrodes. Ph.D., University of Iowa (2008).Spolar, C. Electrochemical Studies of Ethanol and Related Compounds at Magnetically Modified Electrodes. M.S., University of Iowa (1999).Lee, G. G., Leddy, J. & Minteer, S. D. Chem. Comm. 48, 11972-11974 (2012).Lee, G. G. Magnetoelectrocatalysis: Enhanced Heterogeneous Electron Transfer Rates, Gratzel Cells, and MnO2 Electrodes. Ph.D., University of Iowa (2012).Reed, J. J. Magnetic Effects on Hydride Storage in Palladium. M.S., University of Iowa (2012).Zook, L. A. Morphological Modification of Nafion for Improved Electrochemical Flux. Ph.D., University of Iowa (1996).Leddy, J., Amarasinghe, S., Zook, L. A. & Tinoco, F. in Proceedings of the 37th Power Sources Conference 93–95 (1996).Leddy, J. & Coworkers, U.S. Patents (22) on Magnetically Modified Electrochemical Systems: 8,231,988 B, 8,227,134 B2, 7,842,178 B2, 7,709,115, 7,691,638, 7,585,543 B2, 7,041,401 B2, 6,949,179 B2, 6,890,670 B2, 6,514,575, 6,375,885 B1, 6,355,166 B1, 6,322,676 B1, 6,207,313 B1, 6,001,248, 5,981,095, 5,928,804, 5,871,625, 5,817,221, and 5,786,040.

Blood glucose prediction by breath analysis system with feature selection and model fusion.

It has been shown that the concentration of acetone in breath is correlated with the subject's blood glucose level (BGL). Therefore, noninvasive BGL monitoring of diabetics can be achieved by the analysis of components in breath. In this paper, a breath analysis device with 10 gas sensors is designed to measure breath samples. Transient features are extracted from the signals of the sensors. Sequential forward selection is applied on the features to find the most informative ones. In order to reduce the interference brought by the inter-subject variance of breath acetone, global and local BGL prediction models are built and fused. The two models are based on different training strategies and have different advantages. Experiments were conducted using 203 breath samples from 36 diabetic subjects. Results show that the accuracy of the proposed feature is better than other similar features and the model fusion strategy is effective. The mean absolute error and mean relative absolute error of the system are 2.07 mmol/L and 20.69%, respectively.