Surface Plasmon Resonance Biosensor Based on STO and Graphene Sheets for Detecting Two Commonly Used Buffers: TRIS-Borate-EDTA and Dulbecco Phosphate Buffered Saline

In this study, we present a new biosensor based on surface plasmon resonance (SPR) for the detection of two commonly used buffers: Dulbecco Phosphate Buffered Saline (PBS) and TRIS-Borate-EDTA Buffer (TBE). The proposed SPR sensor utilizes a combination of SrTiO3 (STO) and two-dimensional (2D) materials. In the angle interrogation method, using STO can almost double the sensitivity compared to using traditional SPR biosensors. Moreover, using a single sheet of graphene (SSG) can further improve the sensitivity. For PBS and TBE buffers, the highest sensitivities reached are 327.023 and 320.581 degrees/RIU with the structures SSG/35 nm Ag/ 14 nm STO and SSG/50 nm Ag/12 nm STO, respectively. We also investigate a set of 2D nanomaterials and found that the maximum sensitivity can be attained with WSe2 due to its lower real part of the refractive index. The results reveal that the proposed SPR biosensor is an efficient tool for biomedical applications.

Automated summary

We propose a new biosensor based on surface plasmon resonance (SPR) that can detect two commonly used buffers: Dulbecco Phosphate Buffered Saline (PBS) and TRIS-Borate-EDTA Buffer (TBE). The biosensor combines SrTiO3 (STO) and two-dimensional (2D) materials, and using STO can significantly enhance sensitivity compared to traditional SPR biosensors. Additionally, employing a single sheet of graphene (SSG) further improves sensitivity. The highest sensitivities achieved for PBS and TBE buffers are 327.023 and 320.581 degrees/RIU, respectively, using the structures SSG/35 nm Ag/14 nm STO and SSG/50 nm Ag/12 nm STO. Furthermore, the use of WSe2 as a 2D nanomaterial results in maximum sensitivity due to its lower real part of the refractive index. These findings demonstrate the effectiveness of the proposed SPR biosensor for biomedical applications.