Building Molecular Immobilization Platform by Eletrodeposition of NTA Derivatives on Gold Surface and its Applications.

• Main Authors: Hsu, Po-Jung, 許博榮
• Other Authors: Li, Yaw-Kuen
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/k5yn67

碩士 === 國立交通大學 === 應用化學系碩博士班 === 105 === Quartz crystal microbalance (QCM) can convert mass change on the quartz surface to frequency change, so QCM can be used as transducer in biosensor. The adventage of QCM is high sensitivity, which is up to nano gram, and real-time detection of adsorption and dissociation of molecules on quartz surface. Nitrilotriacetic acid (NTA),which consist of one tertiary amine and three carboxylic acid, used to be apply in protein purification and NTA can also form four coordinate bond with transition metal ion, generating NTA-M2+- His-tag-Protein complex by coordination with two histidine in His-tag, an oligomer which usually compose of six to ten histidine. Therefore, NTA widely apply in protein purification, protein immobilization and biosensor. This research synthesized three different length aniline-NTA derivatives and covert those aniline-NTA derivatives into diazonium salts by reaction with NaNO2 under acid condition, and then modify those diazonium salts on gold surface, which was coated on QCM chip, by electrodeposition. We investigate surface physical properties by analysis surface oxidation-reduction voltammetry, surface impedence and contact angle and discover that His-tag-protein binding most on the chip by QCM when modify longest aniline-NTA of the three derivatives. Finally, Using QCM chip, which was modified the longest NTA, as His-tag-biomolecule, such as peptide, protein…etc, immobilization platform to real-time observe association or dissociation reaction of biomolecules and calculate dissociation constant (Kd) of those biochemical reaction.