Quantitative Determination Of Blood Glucose By Raman Spectroscopy

author: Joy

2022-01-07

Quantitative Determination Of Blood Glucose By Raman Spectroscopy

At present, blood glucose detection is generally carried out by blood collection. In short, a certain amount of blood is extracted and the concentration of glucose in the blood is detected by biological or physical methods. A few microliters of blood sample should be taken for the least damage, and the concentration of blood glucose is calibrated by enzymatic reaction. At present, nondestructive testing methods have not been widely used in clinic. The main problems are as follows: 1. The blood glucose concentration is very low, and the clinical accuracy cannot be accurately achieved by traditional physical means;2. Current lossless technical methods cannot obtain direct single information of blood due to skin or other interference, and generally extract relevant information through mathematical processing, resulting in large interference, unstable and inaccurate measurement; 3. There is no internal calibration reference index due to the large difference of individual skin resulting in large spectral difference.Blood glucose can be quantitatively determined by Raman spectroscopy.

Principle: Raman Scattering Spectroscopy

Light on matter scatters both elastic and inelastic. The scattered light of elastic scattering has the same wavelength as the excited light, while the scattered light of inelastic scattering has the longer and shorter components than the excited light, collectively known as the Raman effect.The invention relates to a nondestructive method for quantitative detection of blood glucose using Raman spectroscopy, including the following steps;Laser light from a semiconductor diode, which uses a lens to pass through the skin, is focused into the blood vessels;To obtain the Raman spectrum of blood, through the Raman spectra obtained by Jane characteristic peaks of glucose and hemoglobin characteristic peak intensity division by glucose peak relative strength, calculate the ratio of different blood glucose concentration and glucose peak relative intensity was relatively strong and the concentration curve, the curve as the basis of quantitative measuring blood sugar levels;The relative intensity of glucose peak in Raman spectrum of blood with unknown concentration was compared with the relative intensity - concentration curve of blood glucose to obtain the glucose concentration in blood.
The laser penetrates the skin and focuses into the blood vessels to obtain the Raman spectrum.of blood. The characteristic peaks of glucose and hemoglobin are used to judge the concentration of blood glucose. Thecharacteristic peak of hemoglobin is used as the internal calibration index to overcome the interference of skin and other factors on the signal and the problem of signal size variation. Thus, accurate data of blood glucose concentration can be obtained.The method of nondestructive measurement of blood glucose in skin by Raman spectroscopy includes the following steps: 1) A laser beam from a semiconductor diode is introduced into a lens through an interference filter, and then focused under the skin;
2) Adjust the height of focus so that the focus is in the blood. The height adjustment can be controlled by piezoelectric ceramics or by moving the skin, and the determination of the appropriate focus can be achieved by Raman spectroscopy. If there is a relatively single blood spectrum, it is considered that the location is appropriate;
3) The Raman spectral signal excited by the focus is introduced into the spectrometer after passing through the notch filter or band pass filter. The spectrometer is connected with the CCD detector, and the Raman spectral information such as blood is obtained by THE CCD.
4) Extract the characteristic peaks of glucose and hemoglobin from the spectral data;
5) The relative intensity of glucose peak was obtained by dividing the intensity of glucose characteristic peak (1125cm') and hemoglobin characteristic peak (1549cm') obtained by Raman spectroscopy;

6)The relative strength concentration relationship curve was obtained by calculating the relative intensity of different glucose concentrations and
glucose peaks, which was used as the basis for quantitative measurement of glucose concentrations;

7) The relative intensity of glucose peak in the blood Raman spectrum of unknown concentration was compared with the relative intensity - concentration curve to obtain the glucose concentration in the blood.

Fig 1System Optical Path Structure Diagram.In FIG. 1, 1. Semiconductor laser diode, 2. Interference filter, 3. Bicolor mirror, 5. Reflector, 6. Lens, 7. Slide, 8. Blood vessel, 9. Band pass or holographic filter, 10. Spectrometers, 11.CCD, 12. Computer.

Result:

Fig 2Raman Spectra OfDifferent Blood Glucose Concentrations Obtained From Blood Vessels Under The Skin

Fig 3The Relative Strength - Concentration Curve Of Glucose.

Conclusion:

Raman spectroscopy can quantitatively determine blood glucose, which is a nondestructive testing method, convenient and quick.Using OPTOSKY’S ATR8300 can easily test blood sugar.