Abstract
Self-monitoring of blood glucose forms an important part of the management of diabetes and the prevention of hyperglycaemia and hypoglycaemia. Current glucose monitoring methods either use needle-prick enzymatic glucose-meters or subcutaneous continuous glucose sensors (CGM) and thus, non-invasive glucose measurements could greatly improve the self-management of diabetes. A wide range of non-invasive sensing techniques have been reported, though achieving a level of precision comparable to invasive meters remains a challenge. Optical sensors, which utilise the interactions between glucose and light, offer the potential for non-invasive continuous sensing, allowing real-time monitoring of glucose levels, and a range of different optical sensing technologies have been proposed. These are primarily based upon optical absorption and scattering effects and include infrared spectroscopy, Raman spectroscopy and optical coherence tomography (OCT), with other optical techniques such as photoacoustic spectroscopy (PAS) and polarimetry also reported. This review aims to discuss the current progress behind the most reported optical glucose sensing methods, theory and current limitations of optical sensing methods and the future technology development required to achieve an accurate optical-based glucose monitoring device.
Highlights
Accurate glucose monitoring forms an essential part of the management of diabetes.Glucose is one of the most important sources of energy in living organisms, being used in respiration to produce oxygen, water and, critically, energy in the form of Adenosine triphosphate (ATP) [1]
There are several acute complications associated with diabetes, including Hyperosmolar Hyperglycaemic Syndrome (HHS), Diabetic Ketoacidosis (DKA) and severe long-term effects caused by inflammation of tissues due to high glucose concentrations [6]
This review has summarised the main optical techniques reported in the literature on non-invasive glucose sensing, most of which utilise optical absorption or scattering
Summary
Accurate glucose monitoring forms an essential part of the management of diabetes. Glucose is one of the most important sources of energy in living organisms, being used in respiration to produce oxygen, water and, critically, energy in the form of Adenosine triphosphate (ATP) [1]. Electrochemical methods, which can be enzymatic or use metallic or carbon-based materials, use similar detection principles as blood glucose meters, and often use tears or saliva instead of blood [19] Such sensors show high accuracy in invasive devices, they are affected by pH changes, and non-invasive electrochemical devices cannot provide continuous measurements, which gives them less advantage over subcutaneous CGM monitors. Transdermal sensors usually involve passing a current through the skin and probing the electrical properties of the interstitial fluid, normally using impedance [20,21] or electrolysis-based methods such as iontophoresis [22,23] These sensors offer the major advantage of being wearable, and have reported very strong correlations with glucose concentration; the use of electric currents can cause skin irritation [23,24]. Given the strong penetration of NIR light, the high performance of NIR optoelectronic devices (e.g., highly sensitive detection and efficient light emission), and the simplicity of NIR optics, NIR appears to be one of the most promising technologies for glucose sensing, whilst optical coherence tomography, Raman spectroscopy, polarimetry and photoacoustic spectroscopy are discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
