Abstract：
This study provided a theoretical insight for designing novel plasmonic biosensors using bismuth selenide (Bi2Se3)-Graphene heterostructures. It was a van der Waals (vdWs) stacked configuration composed of gold (Au) film, few quintuple layer (QL) Bi2Se3 and few-layered graphene. In particular, the proposed biosensor was created by Goos-Hänchen (GH) shift rather than phase, resulting in a more sensitive biosensing response. Under the excitation of 632.8 nm, significant sensitivity enhancement performance was obtained via varying the thickness of Bi2Se3-Graphene heterostructures. The best configuration was 32 nm Au film-2-QL Bi2Se3-3-layer graphene, generating the largest GH shift, as high as -1.0202 × 104 µm. Moreover, the highest detection sensitivity was determined to be 8.5017 × 106 µm/RIU, responding to a tiny refractive index (RI) change of 0.0012 RIU (RIU, refractive index unit). More importantly, our proposed biosensor has shown a theoretical feasibility of monitoring virus samples. For example, there was an efficient linear detection range for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, 0~13.44 nanomole (nM)) and its Spike (S) glycoprotein (0~59.74 nM), respectively. It is expected that our proposed plasmonic biosensor has a potential application in performing sensitive detection of SARS-CoV-2.
摘要：
这项研究为使用硒化铋（Bi2Se3）-石墨烯异质结构设计新型等离子体生物传感器提供了理论见解。它是由金（Au）膜组成的范德华（vdWs）堆叠配置，少量五层(QL)Bi2Se3和少层石墨烯。特别是,拟议的生物传感器是由Goos-Hänchen(GH)移位而不是相位创建的，导致更敏感的生物传感反应。在632.8nm的激发下，通过改变Bi2Se3-石墨烯异质结构的厚度获得显著的灵敏度增强性能。最佳构型为32nmAu薄膜-2-QLBi2Se3-3层石墨烯，产生最大的GH位移，高达-1.0202×104µm。此外，最高检测灵敏度为8.5017×106µm/RIU，响应0.0012RIU的微小折射率(RI)变化(RIU，折射率单位)。更重要的是,我们提出的生物传感器已显示出监测病毒样品的理论可行性。例如,严重急性呼吸综合征冠状病毒2型(SARS-CoV-2,0~13.44纳摩尔(nM))及其Spike(S)糖蛋白(0~59.74nM)有一个有效的线性检测范围,分别。预计我们提出的等离子体生物传感器在SARS-CoV-2的灵敏检测中具有潜在的应用。
