Applied Science and Convergence Technology 2018; 27(6): 184-188
Published online November 30, 2018
Copyright © The Korean Vacuum Society.
Tran Thi Dunga,b, and Moonil Kima,b,*
aHazards Monitoring Bionano Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea, bKRIBB School, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
Correspondence to:*Corresponding author: E-mail: firstname.lastname@example.org
Herein, we report a novel surface plasmon resonance (SPR) sensor modified with a toluene-binding domain (TBD) to detect toluene. The TBD was manipulated with cysteines for rapid, easy, and orientation-controlled immobilization of the protein onto an SPR gold surface, due to the specific interaction between bare gold and the thiol group (−SH) of cysteines. After the purification and on-chip immobilization of the recombinant TBD, the thickness of cysteine-tagged TBD was determined to be approximately 1.8 nm according to atomic force microscopic cross-sectional analysis. The SPR analysis of cysteine-tagged TBD adsorption showed that cysteine-tagged TBD binds to gold thin film with high binding affinity. With an SPR-based ligand binding assay, a detectable increase in the SPR response was observed for 15.62 μM of toluene. Owing to the inherent specificity of the TBD, this method showed comparative specificity for the determination of toluene, as it exhibited no SPR response to aromatic compounds such as p-xylene or benzene. Taken together, the results obtained from this study indicate that a TBD-modified SPR sensor system can be useful for detecting toluene, a volatile organic compound widely distributed in the environment.
Keywords: Biosensor, Surface plasmon resonance, SPR, Toluene, Toluene binding domain