On the use of fiber lasers in non-invasive blood glucose monitoring

Abstract Blood glucose monitoring (BGM) is the most important part of diabetes management. In classical BGM, glucose measurement by test strips involves invasive finger pricking. We present results of a clinical study that focused on a non-invasive approach based on volatile organic compounds (VOCs) in exhaled breath. Main objective was the discovery of markers for prediction of blood glucose levels (BGL) in diabetic patients. Exhaled breath was measured repeatedly in 60 diabetic patients (30 type 1, 30 type 2) in fasting state and after a standardized meal. Proton Transfer Reaction Time of Flight Mass Spectrometry (PTR-ToF-MS) was used to sample breath every 15 minutes for a total of six hours. BGLs were tested in parallel via BGM test strips. VOC signals were plotted against glucose trends for each subject to identify correlations. Exhaled indole (a bacterial metabolite of tryptophan) showed significant mean correlation to BGL (with negative trend) and significant individual correlation in 36 patients. The type of diabetes did not affect this result. Additional experiments of one healthy male subject by ingestion of lactulose and 13C-labeled glucose (n=3) revealed that exhaled indole does not directly originate from food digestion by intestinal microbiota. As indole has been linked to human glucose metabolism, it might be a tentative marker in breath for non-invasive BGM. Clinical studies with greater diversity are required for confirmation of such results and further investigation of metabolic pathways.

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Non-Invasive Blood Glucose Monitoring by Means of near Infrared Spectroscopy: Methods for Improving the Reliability of the Calibration Models

The International Journal of Artificial Organs ◽

10.1177/039139889702000509 ◽

1997 ◽

Vol 20 (5) ◽

pp. 285-290 ◽

Cited By ~ 42

Author(s):

U.A. Müller ◽

B. Mertes ◽

C. Fischbacher ◽

K.U. Jageman ◽

K. Danzer

Keyword(s):

Blood Glucose ◽

Near Infrared ◽

Glucose Monitoring ◽

Blood Glucose Monitoring ◽

Least Squares Regression ◽

Non Invasive ◽

Infrared Reflection ◽

Calibration Models ◽

Infrared Reflection Spectroscopy

The feasibility of using near infrared reflection spectroscopy for non-invasive blood glucose monitoring is discussed. Spectra were obtained using a diode-array spectrometer with a fiberoptic measuring head with a wavelength ranging from 800 nm to 1350 nm. Calibration was performed using partial least-squares regression and radial basis function networks. The results of different methods used to evaluate the quality of the recorded spectra in order to improve the reliability of the calibration models, are presented.

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A Review of Non-Invasive Optical Systems for Continuous Blood Glucose Monitoring

Sensors ◽

10.3390/s21206820 ◽

2021 ◽

Vol 21 (20) ◽

pp. 6820

Author(s):

Bushra Alsunaidi ◽

Murad Althobaiti ◽

Mahbubunnabi Tamal ◽

Waleed Albaker ◽

Ibraheem Al-Naib

Keyword(s):

Blood Glucose ◽

Glucose Monitoring ◽

Daily Basis ◽

Glucose Sensing ◽

Blood Glucose Monitoring ◽

Optical Systems ◽

Glucose Levels ◽

Non Invasive ◽

Blood Glucose Levels ◽

Continuous Blood Glucose Monitoring

The prevalence of diabetes is increasing globally. More than 690 million cases of diabetes are expected worldwide by 2045. Continuous blood glucose monitoring is essential to control the disease and avoid long-term complications. Diabetics suffer on a daily basis with the traditional glucose monitors currently in use, which are invasive, painful, and cost-intensive. Therefore, the demand for non-invasive, painless, economical, and reliable approaches to monitor glucose levels is increasing. Since the last decades, many glucose sensing technologies have been developed. Researchers and scientists have been working on the enhancement of these technologies to achieve better results. This paper provides an updated review of some of the pioneering non-invasive optical techniques for monitoring blood glucose levels that have been proposed in the last six years, including a summary of state-of-the-art error analysis and validation techniques.

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