Feasibility Study on FTIR Spectroscopy and Raman Spectroscopy as the Reader of Enzyme-Linked Immunosorbent Assay

• Main Authors: Cheng-Yen Tsai, 蔡承諺
• Other Authors: 江建文
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/by7mda

碩士 === 國立臺灣大學 === 化學研究所 === 105 === Enzyme-Linked Immunosorbent Assay (ELISA) is a very important in vitro diagnostic device (IVDs). Because the early treatment is able to improve the survival rate of cancer patients, where they could go to hospital for screening. Thus, the demand of in vitro diagnosis is increasing annually. In 2016, the global market of immunoassay reached USD 17.16 billion. In ovarian cancer, haptoglobin have been used as a prognosis factor to evaluate the risk of cancer, and we can find clinical tests based on haptoglobin ELISA kits. When the concentration of this protein in the blood is high, it means that increased risk of having ovarian cancer. In contrast, excessively low levels of haptoglobin indicates serious hemolysis. We believe that it is important to estimate the concentration of haptoglobin. However, The detection range of current ELISA reader is poor. Thus, we used FTIR spectroscopy and surface enhance Raman spectroscopy (SERS) as the readout of ELISA to improve the detection range of ELISA. In FTIR based ELISA, we dropped each standard sample on CaF2 window and the solvent was removed by vaccum. Subsequently, the samples was scanned by FTIR. It showed that a peak at 1572cm-1, which was the absorption of TMB2+, a product reacted by chromogen substrate(TMB) and HRP. In SERS, the sample was mixed with gold nanoparticles, as gold nanoparticle could enhance the signal of TMB2+. A peak at 1605 cm-1 was detected. It found that the intensity of the peak was increasing as the concentration of TMB2+ increased. In conclusion, we demonstrated the feasibility that FTIR and SERS could be used as ELISA readout, and the new method also expands the detection range of Hp. We look forward to improving existing ELISA methods by this research.