Protein Based Localized Surface Plasmon Resonance Gas Sensing
Meisam Omidi1,3, Gh. Amoabediny2,3, F. Yazdian1,3**, M. Habibi-Rezaei4,5
1Faculty of New Science and Technology University of Tehran, Tehran, Iran 2Department of Biotechnology and Pharmaceutical Engineering, Faculty of Chemical Engineering, School of Engineering, University of Tehran, Tehran, Iran 3Research Center for New Technologies in Life-Science Engineering, University of Tehran, Tehran, Iran 4School of Biology, College of science, University of Tehran, Tehran, Iran 5Nanobiomedicine Center of Excellance, University of Tehran, Tehran, Iran
We apply the localized surface plasmon resonance (LSPR) of gold nanoparticles (GNPs) covalently coupled with cytochrome c (cyt c) to create a nanobiosensor for detecting hydrogen sulfide (H2S) in the range of 15–100 ppb. Monolayer formation of GNPs on glass surface functionalized with 3-aminopropyltrimethoxysilane (APTMS) is performed for fabricating a chip-based format of the optical transducer. By chemical introduction of short-chain thiol derivatives on cyt c protein shell via its lysine residues, a very fast self-assembled monolayer (SAM) of cyt c is formed on the GNPs. Significant shifts in the LSPR peak (ΔλLSPR) are observed by reacting H2S with cyt c. Results show a linear relationship between ΔλLSPR and H2S concentration. Furthermore, shifts in the LSPR peak are reversible and the peak positions return to their pre-exposure values once the H2S is removed. The experimental results strongly indicate that the protein based LSPR chip can be successfully used as a simple, fast, sensitive and quantitative sensor for H2S detection.