Designing Efficient Localized Surface Plasmon Resonance-Based Sensing Platforms for Direct Detection of Hydrogen Sulfide

In this paper, a rapid and sensitive method for colorimetric sensing of hydrogen sulfide (H2S) in aqueous solutions is illustrated. A novel biosensor is developed based on one-shot adsorption of chemically-modified cytochrome c (cyt c) onto gold nanorods (Au NRs). Here by reacting H2S with protein heme centre, the protein conformation changed. The conformational changes occurring in the protein altered the spectral characteristics by change in the dielectric properties of Au NRs. The limit of detection (LOD) and sensitivity of Au NRs/cyt c biosensor were evaluated by using UV– visible spectroscopy. According to the experiments, it is revealed that sulfide anions can be detected at a concentration of 2.0 μM (0.75 ppb) by Au NRs/cyt c biosensor. This simple and cost-effective sensing platform provides a rapid and convenient detection for sulfide anions at concentrations far below the hazardous limit.