A Love wave sensor with a phononic parylene-C wave guiding layer is proposed to detect the VEGF secreted during the selective platelet activation process, where arrays of a different material (filling material) are fabricated in the parylene-C films. The effects of the structural design parameters (period width and period number) on the electric response of sensors are investigated. As the period width is increasing, the resonance frequencies are shifted, and the insertion losses are changed accordingly; however, along with the period number varies, there is no obvious change in the sensor response. The numerical results from finite element method (FEM) illustrate that with specific period width the acoustic waves at the vicinity of resonance frequency could be enhanced through the phononic sensing area of Love wave sensor, when signals of other frequencies are attenuated. The results indicate a potential Love wave sensor with high sensitivity and reliability in the cell biology applications.