Design and optimization of an optical ring resonator based biosensor for cancer detection

Optical biosensors are seeking the attention of researchers as a very effective instrument due to their accurate, label-free and instantaneous sensing capabilities. Nonetheless, the optimization of sensor configurations is essential to ensure consistent and reliable sensing performance. This work proposes an intriguing optical ring resonator (ORR) based biosensor design for detecting various cancerous cells. A detailed numerical analysis of the proposed biosensor was performed using the finite element method (FEM) implemented in COMSOL Multiphysics software. The refractive index (RI) values ranging from 1.36 to 1.401 was investigated concerning six different types of cancer cells including blood cancer, skin cancer, adernal gland cancer, cervical cancer, and two types of breast cancer. The spectral response of the ring resonator and the shift in resonance wavelength due to changes in the RI between cancerous and healthy cells were precisely examined through systematic numerical analysis. Additionally, the structural characteristics of the proposed ring resonator-based biosensor were optimized to enhance its effectiveness in distinguishing diseased cells from healthy ones. The highest sensitivity, figure of merit, and quality factor obtained were 392.86 nm/RIU, 144.17 RIU⁻¹, and 601.91, respectively, recorded for PC-12 cells. This proposed biosensor depicts improved sensitivity compared to the existing ORR sensors. The results demonstrate a meaningful improvement in ORR biosensor capabilities, facilitating the design of efficient sensing platforms for biosensing of cancer cells from cellular fluid samples.