Optomechanical Racetrack Cantilever Biosensor: Bridging Chemical and Cellular Detection

A novel optomechanical biosensor architecture integrating an optomechanical racetrack-cantilever biosensor with a flexible cantilever is designed for simultaneous detection of chemical and cellular analytes. Pressure loads induced by glucose, dopamine, and MCF-7 cancer cells were modeled as mechanical deflections transduced into resonance wavelength shifts. Finite element simulations in ANSYS and COMSOL were validated against analytical beam theory with deviations below 1%. Distinct resonance signatures were observed for chemical and cellular analytes, demonstrating the capacity for analyte discrimination. PDMS cantilevers exhibited mean sensitivities of approximately 1.69 pm/kPa and maximum responses of 5.34 pm/kPa, whereas SiO₂ devices showed negligible sensitivity. These results demonstrate, through finite-element simulations and analytical modeling, the proof-of-concept operation of a racetrack-cantilever optomechanical biosensor. The study highlights key trends and limitations rather than providing an exhaustive experimental explanation, thereby offering a design foundation for future fabrication and validation.