Suspended graphene waveguides over micrometer-scale metal-mesh screens were used as platforms for Raman scattering. Raman signals of B. megaterium spores were found sensitive to in-plane rotations and tilt of the waveguides with respect to the incident linearly polarized pump beam. When at plasmonic resonance for the equivalent long wavelength of the vibration frequency, the Raman signal exhibited an additional quadratic effect.