Near-Infrared Light Emitting Diode Based Non-Invasive Glucose Detection System

Diabetes mellitus is a common disease that has affected people since antiquity. The complexity of diabetes mellitus lies in the fact that it requires continuous management in order to prevent serious complications. Various methods for managing diabetes mellitus through monitoring blood glucose levels have been studied and developed, and the most widely used method includes using an invasive blood glucose meter. Since the invasive blood glucose meter poses a major inconvenience for patients, in this study, we sought to develop a non-invasive blood glucose meter. We therefore proposed the development of a non-invasive blood glucose measurement system that is based on near-infrared spectroscopy. The system developed was composed of a light source for emitting different wavelengths, a light detector unit, and a computing system for recording signals. A prepared glucose solution was injected into a quartz cuvette and light at 780–1650 nm was emitted to pass through the cuvette. The degree of reaction was determined by recording the change in wavelength. The wavelength band used for the experiment was 780–1000 nm and the resolution was 20 nm. The glucose concentration was determined to be between 50 to 400 mg/dl compared to the normal range of 80 to 120 mg/dl. By examining which wavelength bands specifically reacted with glucose, we observed that the wavelength bands that decreased or increased in response to the glucose concentration were at 780 nm and 940 nm. For wavelength bands at 1000 nm or above, light was also absorbed by water and therefore it was difficult to distinguish the results. The most reliable wavelength band was at 940 nm with an R ² of 0.9806. In conclusion, the near-infrared light emitting diode based non-invasive glucose detection system performed well and is expected to be a superior method for monitoring blood glucose levels in diabetes mellitus.