Graphene-MoS2-Au-TiO2-SiO2 Hybrid SPR Biosensor: A New Window for Formalin Detection

Md. Biplob Hossain, M. M. Rahman Khan, Md. Sadiqur Rahman, S. S. Bin Badrudduza, M. M. Sabiha, Md. Masud Rana
2019 Journal of Materials and Applications  
In this article, numerically a surface plasmon resonance (SPR) biosensor is developed based on Graphene-M­­­­OS2-Au-TiO2-SiO2 hybrid structure for formalin detection. This developed sensor sensed the presence of formalin by applying attenuated total reflection (ATR). In ATR method, we developed and observed two characteristics curve, one is "SPR angle versus minimum reflectance (Rmin)" and another is "SPR frequency (SPRF) versus maximum transmittance (Tmax). In the proposed sensor, Chitosan is
more » ... sed as probe legend to perform specific reaction with the formalin (40% formaldehyde) as target legend. Here, graphene and MoS2 both are used as biomolecular acknowledgment element (BAE). And TiO2 as well as SiO2 bilayers are used to improve sensor sensitivity and Gold (Au) is to sharp SPR curve. In numerical results, the variation of SPRF and SPR angle for inappropriate sensing of formalin is quiet insignificant which confirms the absence of formalin. On the other hand, these variations for appropriate sensing is considerably significant that confirms the presence of formalin. At the end of this article, a study of variation of sensitivity of the proposed biosensor in corresponding to the increment of refractive index with a refractive index step 0.01 RIU is measured. In inclusion of TiO2-SiO2 bilayers with Graphene-M­­­­OS2, maximum sensitivity of 85.375% more is numerically reported.
doi:10.32732/jma.2019.8.2.51 fatcat:iua5olkz3rg6fbjrkiscucdiaa