Highly sensitive nitride-based SPR biosensor for efficient adrenal gland/blood/breast/cervical/skin cancer detection

The current study outlines four extremely sensitive SPR-based cancer sensors that have the highest sensitivity to date for the quick and accurate diagnosis of six major cancer cells, including adrenal gland, breast (t1/t2), cervical, blood, and skin cancer, where the first two are blamed as the most fatal and infected ones, respectively. Four nitrides—AlN, GaN, InN and Si₃N₄—are employed in four distinct sensor configurations to identify the aforementioned six cancer cell types. The sensor with AlN is found the most suitable for skin/breast (type-1) cancer detection with sensitivity (S) and quality factor (QF) of 370/385 Deg/RIU and 92/113 RIU⁻¹, the GaN based structure for adrenal gland/blood cancer detection with S and QF of 400/400 Deg/RIU and 108/102 RIU⁻¹, the InN-based structure for breast cancer (type-2) detection with S and QF of 414 Deg/RIU and 108 RIU⁻¹, and finally the Si₃N₄-based structure for cervical cancer detection with S and QF of 341 Deg/RIU and 92 RIU⁻¹, respectively. Furthermore, AlN and GaN based sensors can sense all the six types of cancer cells with a minimum sensitivity of around 230 Deg/RIU, an accepted number as per some recently reported results. Finite element method-based simulator COMSOL is used to study and optimize the structures considering an operating wavelength of 633 nm, anticipating for a low-cost sensor prototype. The highest reported sensitivity in this study is 414 Deg/RIU with QF of 108 RIU⁻¹ for the Au-Ag-InN configuration for the breast cancer (type-2) detection.