Application Of THz Technology In Spectrum Detection And Tumor Diagnosis Of Chinese Herbal Medicine

Terahertz Time-Domain Spectroscopy(THz-TDS)is a new technology developed since the 1980s.The use of photoconductive method to generate THz radiation pulse,with a large broadband,high signal to noise ratio,can work at room temperature.The amplitude and phase in the frequency domain is obtained by Fourier transform,and the information of the sample is obtained by measuring the change of the THz electric field with time by using the pulse transmission sample or the reflection on the sample.THz-TDS technology is currently used to study the properties of materials in the terahertz band and physical phenomena.This thesis describes the applications of terahertz techniques in the field of medicine and biomedical,including the following parts:First of all,in this paper,terahertz time-domain spectroscopy(THz-TDS)was used to measure different water content of Gastrodia elata and different chrome content of gelatin samples.The frequency-dependent absorption coefficient curve of the dry process was calculated,and the absorption coefficient curve of the different chromium content gelatin was calculated by using the thickness of the sample.It was found that the water content and the absorption coefficient,the chromium content and the absorption coefficient of gelatin showed a linear positive correlation,so as to evaluate the quality of the sample according to the measured results?Secondly,the terahertz time-domain spectroscopy(THz TDS)was used to measure the THz spectra of artemisinin,dihydro artemisinin,artesunate and artemether,and the characteristic absorption spectra were obtained in the range of 0.2 to 2.7 THz.Compared with the experimental results and the previously reported data,our experimental data show that most of the resonance peaks are consistent with the literature[24],but the peak position and intensity are slightly different,and some new peaks have been observed.Furthermore,the influence of sample preparation and data processing method on the results of the data and the relationship between molecular structure and peak position are discussed.In addition,the validity of the data is confirmed.This study provides a reference for the further study of the properties of artemisinin and its derivatives,and provides a rapid and effective method for the identification and quantitative analysis of artemisinin and its derivatives.At last,the terahertz spectral imaging technique was used to detect the normal liver tissues and liver tumor tissues,normal Kidney tissues and Kidney tumor tissues,respectively.Based on their terahertz tspectra,the absorption coefficient of the normal tissue and the tumor tissue can be indentified.Then the terahertz imaging of liver tissue and kidney tissue was carried out by point-by-point scanning terahertz imaging setup.And the THz images in the time-domain display mode and the frequency-domain display mode were obtained respectively.The imaging results could distinguish the tumor tissue from the normal tissue.Then,the imaging results are analyzed,and the existing problems and solutions are put forward,which lays the foundation for the research of terahertz technology in biomedical field.