Immobilization of genetically engineered fusion proteins on gold-decorated carbon nanotube hybrid films for the fabrication of biosensor platforms

We have demonstrated the fabrication of the biosensor platforms by means of the integration of the genetically engineered fusion proteins and the uniform gold nanoparticle-deposited multi-walled nanotube hybrid (Au-MWNT-HB) films for the detection of C-reactive protein (CRP). Au-MWNT-HB films were used as a good electrochemical transducer due to their excellent electrical properties and large surface areas for the signal transduction, while the genetically engineered fusion proteins, or 6His–GBP–SpA fusion proteins, specifically bind onto the surface of the Au-MWNT-HB films and efficiently immobilize bioreceptors for the detection of CRP. As-obtained biosensor platforms were characterized by electrochemical and optical analysis and revealed better performance compared to conventional Au-based biosensors. The concept delineated herein opens a new insight into nanobiotechnology through the integration of genetically engineered biomaterials with carbon nanotube (CNT)-based nanohybrids for emerging applications.

Label-free electrochemical biosensor based on bioinspired nanocomplex was developed for the CRP detection by combining the GBP-SpA fusion protein as a bioreceptor with Au nanoparticle-decorated MWNT nanohybrid.Figure optionsDownload high-quality image (122 K)Download as PowerPoint slideResearch highlights
► Multi-walled carbon nanotube (MWNT) was deposited with gold nanoparticles to create a nanocomplex.
► A facile fabrication method and intensive ultrasound irradiation procedure were performed for electrochemical applications via antigen-antibody interaction as both biolinkers and capture ligands immobilized onto the particle surface.
► The fusion proteins can be directly selfassembled onto the gold surfaces via the GBP portions without any complicated chemical modifications of the gold surface, and the antigenic portion serves as a capture ligand for its antibody.
► Au-MWNT nanohybrids as an electrochemical substrate based on their excellent electrical properties and large surface areas could be useful to the new detection tools such as multiplex bioanalysis, electrochemical analysis and biomimetics.