A Novel Electrically Protein-manipulated Microcantilever Biosensor with Enhanced Probing Protein Immobilization

• Main Authors: Chien-Ying Huang, 黃建穎
• Other Authors: Jeng-Shian Chang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/48472877713142503701

碩士 === 國立臺灣大學 === 應用力學研究所 === 94 === Recognition and quantification of bio-molecules are irreplaceable in biomedical tests and disease diagnosis. A microcantilever biosensor embedded with electrodes for manipulation and enhancement of probing protein immobilization onto sensing surfaces has been demonstrated. The electrically protein-manipulated, nanomechanics-based biosensor is featured with significant reduction of usage in probing biomaterials, label-free, high sensitivity, low production cost and massive parallel analysis potential; in addition, miniaturization and portability are the tendency of its future development. For bio-sensor production, the probing protein immobilization process is ineffective, which invariably leads to a dramatic waste in proteins and thus a considerable increase of cost. Based on changes in electrical charges of the protein in different solution environments, the approach in this study enhanced the immobilization efficiency of probing protein onto the surfaces of microcantilever biosensors by applying electrical manipulation technique. With the merit of MEMS technique, it allows highly fabrication-compatible integration into microcantilever biosensors with electric devices. Connecting ITO conductive film created extrinsic fluidic electrodes with intrinsic fluidic gold and nickel electrodes, to make a microcantilever biosensor that is capable of manipulating electrical field. It is evident that higher amount of probing antibody molecules immobilized onto sensing surfaces captures more detected specific molecules, indicating greater deflection and stresses as well. This however leads to significant cost in biosensor. By applying electrical fields onto charged proteins, the protein manipulation exhibits a significant increase of probing immobilized proteins. As expected, most charged proteins distributed in solution are effectively attracted onto the sensing area within electric fields in high voltage. Under the influence of electrical field, the experiment successfully increased the effectiveness of probing protein immobilization by 8 times in which the microcantilever was used in real-time measurement of bio-molecules, and its deflection indicates a proportional concentration amount of antigen-antibody interaction. With such a novel approach, enhanced probing protein immobilization and thus dramatic reduction in protein usage have been greatly achieved in this work. Further effort for microcantilever biosensors is required in pursue of accreditation in pre-marketing censorship and new demonstration of its applications.