Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb) bacteria, is a widespread disease worldwide, where early diagnosis plays a crucial This study presents a one dimensional binary photonic crystal (1D PhC) biosensor optimized for higher sensitive and accurate detection of Mtb in blood samples. By using Si and SiO \(_2\) layers, the sensor’s periodic structure detects Mtb through refractive index (RI) variations induced by antigens, manifesting as shifts in the photonic band gap and defect modes. Using the TMM, the design achieves exceptional sensitivity, with the optimum sensitivity found to be 2775.63 nm/RIU, supported by optimized parameters such as incident angle, defect layer thickness, and central wavelength. The comparative analysis highlights the superior performance of the proposed sensor compared to existing techniques, boasting a detection limit of as low as \(6.27 \times 10^{-5}\) RIU. This compact and cost-effective sensor offers immense potential for early TB detection in clinical applications.
