Improving immunosensor performance through oriented immobilization of antibodies on carbon nanotube composite surfaces

详细信息    查看全文

• 作者：Sara Puertas^a ; ¹ ; ^{selmer@unizar.es} ; Marí ; a de Gracia Villa^b ; ¹ ; ^{graciavilla@gmail.com} ; Ernest Mendoza^c ; ^{ernest.mendoza@upc.edu} ; Cecilia Jim&eacute ; nez-Jorquera^b ; ^{cecilia.jimenez@csic.es} ; Jesú ; s M. de la Fuente^a ; ^{jmfuente@unizar.es} ; C&eacute ; sar Ferná ; ndez-Sá ; nchez^b ; ^{cesar.fernandez@imb-cnm.csic.es} ; Valeria Grazú ; ^a ; ^{vgrazu@unizar.es}
• 关键词：Carbon nanotubes ; Antibody ; Oriented immobilization ; Immunoelectrochemical sensor ; Carbodiimide chemistry
• 刊名：Biosensors and Bioelectronics
• 出版年：2013
• 出版时间：15 May, 2013
• 年：2013
• 卷：43
• 期：Complete
• 页码：274-280
• 全文大小：673 K

文摘

We report the straightforward oriented covalent attachment of antibodies (Abs) on the surface of carboxylated multiwalled carbon nanotube-polystyrene (MWCNT-PS) materials. The combination of this composite material, applied as a robust electrochemical transducer platform, and its covalent functionalization with Abs in a controlled way by means of a two-step process, could contribute to the development of highly sensitive immunosensor devices. Using the simple and versatile carbodiimide chemistry, Abs were attached to the carboxylic groups of the MWCNT-PS composite surfaces via their superficial amine groups. By taking into account the Ab isoelectric point and the net charge of the composite surface, we engineered an immobilization process to achieve the oriented binding of the Ab molecules by favoring an ionic pre-adsorption step before covalent binding occurred. Thus, the antigen binding capacity of the attached Abs was enhanced by up to 10 times with respect to the capacity estimated for a random spatial distribution of these molecules. The proposed strategy would also serve as a model for the efficient biofunctionalization of other carboxylated carbon-based polymer composite materials with potential applications in the biosensor field.