Near-infrared Non-invasive Blood Glucose Monitoring Technology Research

Near Infrared Spectroscopy (NIRS) analytic technique has some good characters, such as high speed, good precision, convenient operation, reagent-free, non-invasive (NI) and low cost. It is widely used in the biomedicine field at present. NI measurement of multiple physiological items of human body by NIRS is one of important issues in the biomedicine field. The blood glucose is an important criterion to measure human healthiness. People whose blood glucose is unbalanced would dangerous for their life, so it is necessary for NI blood glucose measurement. NI blood glucose measurement by NIRS has been explored in this paper.First of all, according to the basic theory of NIRS, with the forearm wrist as measurement location, the foundational issue of NI blood glucose measurement has been studied with the range of 1300—1850nm wavelength by using the Diffuse Reflectance mode. The calibrated model of NI blood glucose measurement and the technology process have been established. With the modularized design idea, the system framework of NI blood glucose measurement has been designed.Then, the Monte Carlo model of light transportation in bio-tissues has been established and the three-layered parallel tissues of skin have been modeled. The regularity of distribution of total photon energy, radial resolving power of diffusereflectance R(r) vs radius r , angular resolving power R(a) vs angle a, and internal fluence F(rz) vs radius r and thickness z have been simulated. The analytic result of0.05cm ≤ d ≤ 0.1cm and β≥18° can be used to guide the design of fibre-opticsprobe.Finally, with HP-2000-LL tungsten halogen lamp as light source, the NIR256 NIR spectrometer is used to collect spectrum by quartz fibre conducting light. According to result of Monte Carlo simulation, a fibre-optics probe has been designed. The hardware system structure of NI blood glucose measurement is established.The ultimate objective of studying NI blood glucose measurement is to developportalble and microminiaturing NI blood glucose measuring apparatus, which willappropriate for family. It is an important direction of NIR study in the biomedicinefield.