Study on the interaction between Methylene violet and DNA using a surface plasmon resonance based biosensor

• Main Authors: Yun-Chun Lan, 藍允君
• Other Authors: Wen-Chi Tsai
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/69945859081098984527

碩士 === 中國文化大學 === 生物科技研究所 === 96 === The efficient and rapid detection on molecular interactions between small molecules and target DNA is an important step in the discovery of drugs intended for use in therapy. Traditional analysis of the binding between DNA and DNA binding molecules were performed by footprinting and filter binding assay. These assays did not allow a real time study of association and dissociation with DNA. In this study, an optical biosensor, based on surface plasmon resonance was used as a new analytical device to investigate the interaction between bio-molecules. The device provides a fast and label free detection platform. To examine the interaction between small molecule and DNA, calf thymus DNA and methylene violet was used as a model system. The immobilization of DNA onto gold surface was optimized. Covalent binding via ZrO2 showed the best results. Binding affinity constant can be estimated by dynamics evaluation. The association constant (KA) of methylene violet binding to calf thymus DNA was 150 1/M. The KA of daunomycin binding to ctDNA was 780 1/M. Regeneration process of methylene violet was advantageous in terms of convenience and cost saving. HCl and NaOH was used to break up the binding between DNA and methylene violet. The optimum result was obtained with 0.001 M NaOH as the regeneration solution.