Research On Measurement Technology Of Cartilage Tissue Based On Terahertz Spectroscopy

With high durability and complex biomechanical characteristics, articular cartilage plays an important role in human activities. But its auto repairing ability is limited, once its principal component content and structure have changed, it may induce cartilage degeneration and related joint diseases. Therefore, it is very necessary for the detection of articular cartilage and its component. In recent years, the applications and research of terahertz technology are increasingly valued and have made especially heartening strides in the field of medicine. Compared with traditional methods, the terahertz radiation is low-energy and non-ionizing, whose spectral-fingerprinting capability is well-known in the biological world. It also has penetration for non-polar substances, which can detect a certain depth of the biological tissue information. As such, THz has a great application potential in diagnosis of articular cartilage and other commonly occurring major diseases.This thesis discusses the theory and application of terahertz time-domain spectroscopy and terahertz imaging technology, including the optical constants extraction method of samples. Then this paper briefly introduces the physiological and pathological conditions of the articular cartilage, the main methods of articular cartilage detection. Based on the terahertz technology, it focuses the research on the measurement technology of cartilage tissue. By using the terahertz transmission spectrum and imaging technology to analyze the cartilage, tendon and skin tissue, it verifies the feasibility of using terahertz technology to detect the water content of biological collagen tissue. Also the paper realizes the research of fresh cartilage tissue, including the major component of the protein. As the essential component in cartilage tissue, the content of the chondroitin sulfate has been detected. The parameters such as refractive index and absorption coefficient are calculated and made a thorough analysis, which can get the relation between the substance content and the absorption coefficient. Also, there are some research on the interaction between the chondroitin sulfate, collagen, hyaluronic acid and aminoglucose, which are all the major component in the cartilage. The results indicate that the terahertz time-domain spectroscopy can detect the interaction of different proteins, and the absorption coefficient can be used as identification of the parameters of the different protein difference. At the same time, the absorption coefficient and refractive index are calculated, both of which are acquired by the terahertz technology, and the absorption peak of the absorption spectrum are analysed. Based on the current development of terahertz technology, the opportunities and challenges in biomedical applications are analyzed, which provides support for the application of terahertz technology in the detection of articular cartilage.