Executive Summary : | The detection of cancer-specific biomarkers, such as microRNA (miRNA), is crucial for early-stage prediction, diagnosis, and monitoring stages of cancer disease. MicroRNA reveals differential expression levels in various cancers, affecting cellular transformation, carcinogenesis, and metastasis. Accurate and precise bio-molecule detection is essential in healthcare monitoring, and conventional detection techniques lack specificity, sensitivity, resolution, and fast response time. Several photonic approaches have been demonstrated for bio-molecule detection, such as optical waveguides, fibre Bragg gratings (FBG), Mach-Zehnder interferometers, surface-plasmon resonance (SPR), and optical microcavities. However, there is limited research on the latest two-dimensional (2D) materials-based optical FBG biosensor for early cancer detection. This project aims to develop ultrasensitive, high resolution, fast response, and highly tumor-specific miRNA detection technology based on a 2D material (antimonene) coated etched FBG device for early cancer detection for healthcare diagnostic applications. The method involves fabrication of the FBG sensor using the phase mask technique, surface functionalization of the sensor with gold nanoparticles (AuNP), and attachment of gold nanorods (AuNRs) with single strand DNA (ssDNA) to enhance the evanescent signal. The optical EFBG sensor Bragg wavelength is sensitive to small changes in the refractive index due to bio-molecular interaction. The injection of complementary miRNA on the EFBG sensor surface binds to the ssDNA and desorbed from the 2D material, leading to the refractive index change and the Bragg wavelength shift. The concentration of miRNA can be easily monitored in real-time based on the Bragg wavelength shift of the EFBG biosensor. |