Yadav Jay Kumar, Tripathy S K
Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, 788010, Assam, India.
Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, 788010, Assam, India.
Biosens Bioelectron. 2025 Nov 1;287:117753. doi: 10.1016/j.bios.2025.117753. Epub 2025 Jul 3.
In this article, we have proposed a novel Kretschmann's configuration-based surface plasmon resonance (SPR) sensor structure with gold (Au) or silver (Ag) and perovskite material, to detect the change in refractive index (RI) due to Deoxyribonucleic acid (DNA) hybridization. The proposed SPR sensor structure consists of SF01/CrO/(Au/Ag)/perovskite/graphene/analyteslayer. Each layer of the proposed structure is judiciously optimized by observing the minimum reflectance (R→0), and FWHM (width) value using Fresnel reflection, and transfer matrix method (TMM). Moreover, we have developed a mathematical model to calculate the surface plasmon generation and quality factor for the graphene layer due to the injection of electrons to the upper sub-band from the lower sub-band of graphene, which helps to understand the interaction with the analyte sample. Reflectance spectra demonstrate a significant shift in resonance angle for ssDNA and dsDNA. Furthermore, we have analyzed the performance parameters and observed outstanding sensitivity, remarkable percentage change in quality factor, extraordinary percentage change in figure of merit (FoM), and dip figure of merit (DFoM) in the case of silver (Ag) in contrast to gold (Au) using CsSnI perovskite material layer. The enhancement of performance parameters is due to better interaction of graphene with the free charge carriers of DNA, which leads to molecular mass or weight change during the hybridization. Therefore, the proposed SPR sensor might be a prominent biosensor for detecting DNA hybridization.
在本文中，我们提出了一种基于Kretschmann结构的新型表面等离子体共振（SPR）传感器结构，该结构包含金（Au）或银（Ag）以及钙钛矿材料，用于检测由于脱氧核糖核酸（DNA）杂交引起的折射率（RI）变化。所提出的SPR传感器结构由SF01/CrO/(Au/Ag)/钙钛矿/石墨烯/分析物层组成。通过使用菲涅尔反射和传输矩阵法（TMM）观察最小反射率（R→0）和半高宽（宽度）值，对所提出结构的每一层进行了合理优化。此外，我们开发了一个数学模型，用于计算由于电子从石墨烯的下子带注入到上子带而在石墨烯层中产生的表面等离子体和品质因数，这有助于理解与分析物样品的相互作用。反射光谱表明单链DNA和双链DNA的共振角有显著偏移。此外，我们分析了性能参数，发现在使用CsSnI钙钛矿材料层的情况下，与金（Au）相比，银（Ag）的灵敏度出色、品质因数的百分比变化显著、品质因数（FoM）的百分比变化非凡以及凹陷品质因数（DFoM）出色。性能参数的提高归因于石墨烯与DNA的自由电荷载流子之间更好的相互作用，这在杂交过程中导致分子质量或重量的变化。因此，所提出的SPR传感器可能是一种用于检测DNA杂交的杰出生物传感器。
