Analysis of glucose concentrations in blood solutions using FTIR and Raman spectroscopy methods

The current market provides a range of invasive technologies for measuring blood glucose levels. These invasive methods often lead to discomfort, require significant time investment, and incur high costs, highlighting the urgent need for innovative and more effective glucose measurement techniques. Non-invasive blood glucose measurement (NGM) poses considerable challenges for both academic and industrial sectors. Presently, there is a notable increase in the application of electrical and optical devices in the medical field for clinical and research purposes. Additionally, advancements in Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy have been made. This study utilizes a combined approach of FTIR and Raman spectroscopy to identify and differentiate the molecular bonds between glucose and hemoglobin, specifically within the wavenumber range of 4000 cm^-1 to 400 cm^-1. Distinct variations in atomic types and bonding characteristics are observed across different wavenumber ranges. The experiments conducted in this study employed invasive blood samples, with FTIR spectroscopy performed on a potassium bromide tablet, while Raman spectroscopy was conducted on a glass slide. The analysis of the experimental results reveals that as blood glucose concentration increases, the intensity of absorption and the area of the FTIR spectrum decrease, whereas the intensity of Raman signals and the area under the curve increase. These observed decreases and increases are believed to be related to the formation of new hydrogen bonds, as well as a reduction in scattering and an enhancement of Raman intensity following the dissolution of glucose in the bloodstream.