As detection of specific deoxyribonucleic acid (DNA) sequences is of great importance in diagnosing many fatal and genetic diseases, there have been renewed interests in designing highly sensitive label-free DNA detection platforms. This paper presents a molybdenum diselenide (MoSe₂)-graphene hybrid structure-based surface plasmon resonance (SPR) biosensor with capability of detecting single-nucleotide polymorphism (SNP) and DNA hybridization events. Because of its better absorption capability the MoSe₂ layer provides strong excitation energy which induces huge charge carrier transfer while the graphene layer serves as a biomolecular recognition element to capture bio-analytes through π-stacking force. The silver (Ag) layer is attached to the BK7 prism by a very thin titanium (Ti) adhesion film which also serves as oxidization and corrosion protection layer. The biosensor is optimized by numerical modeling and the optimum structure has an excellent sensitivity of 215.5°/RIU which is better than other reported works. It has been demonstrated that when target DNAs are attached to the probe DNAs pre-immobilized on the sensing surface the change of SPR angle is insignificant for mismatched DNA strands while it is highly prominent for complementary DNA strands. Thus, the proposed sensor can effectively distinguish hybridization event and SNP by examining the level of changes in resonance angle and reflectance spectrum.

由于检测特定的脱氧核糖核酸 (DNA) 序列在诊断许多致命和遗传疾病方面具有重要意义，因此人们对设计高灵敏度的无标记 DNA 检测平台重新产生了兴趣。本文提出了一种基于二硒化钼 (MoSe ₂ )-石墨烯混合结构的表面等离子体共振 (SPR) 生物传感器，具有检测单核苷酸多态性 (SNP) 和 DNA 杂交事件的能力。由于其更好的吸收能力，MoSe ₂层提供了强大的激发能量，导致巨大的电荷载流子转移，而石墨烯层作为生物分子识别元件通过π捕获生物分析物- 堆叠力。银 (Ag) 层通过非常薄的钛 (Ti) 粘合膜附着在 BK7 棱镜上，该膜也用作氧化和腐蚀保护层。生物传感器通过数值建模优化，最佳结构具有215.5°/RIU的优异灵敏度，优于其他报道的工作。已经证明，当目标 DNA 连接到预固定在传感表面上的探针 DNA 时，SPR 角的变化对于错配的 DNA 链来说是微不足道的，而对于互补的 DNA 链则非常突出。因此，所提出的传感器可以通过检查共振角和反射光谱的变化水平来有效区分杂交事件和 SNP。