This chapter explores the design and application of optical Tamm modes within dual-metal, quasi-periodic photonic structures, with a focus on biomedical sensing. By arranging alternating layers of SiO2 and Ta2O5 based on the Fibonacci sequence, we construct a photonic architecture that incorporates a central cavity—engineered specifically to interact with biological samples such as blood. The study reveals the presence of three distinct resonance dips within the photonic bandgap. Notably, one of these resonances remains stable despite variations in the surrounding refractive index, enabling a dual self-referenced sensing approach. We apply this concept to monitor changes in blood refractive index across different developmental stages of the malaria parasite. As the parasite progresses—from healthy red blood cells to the ring, trophozoite, and schizont phases—a consistent redshift in resonance wavelengths is observed. Additionally, we evaluate how varying the cavity thickness influences the resonance characteristics, identifying optimal geometries that enhance sensitivity and sensor performance. Numerical simulations yield key performance metrics, with refractive index sensitivities ranging from approximately 383 to 425 nm/RIU. Detection accuracy and quality factor values also demonstrate strong potential, with measured ranges of 0.0664–0.0792 nm−1 and 55–65, respectively. This dual-mode sensing method not only improves reliability by providing an internal reference but also broadens the functional wavelength range for detection. The use of quasi-crystalline photonic structures inspired by Fibonacci sequences presents a promising direction for the development of advanced optical biosensors and precision diagnostic tools.