This paper presents the integration of piezoelectrically actuated flexural plate wave devices in a custom designed fluidic cell for biosensing in liquid. The flexural plate wave devices have a wavelength of 60 μm with an antisymmetric A0 mode analytically predicted to occur at 45MHz. The flexural plate wave devices and fluidic cell are used to measure protein adsorption from solution. As a biosensing proof of concept, the adsorption of bovine serum albumin (BSA) to the silicon surface of the FPW from a 500 μg/mL solution in phosphate buffered saline (PBS) is measured with an ultimate frequency shift of about 15 kHz. This constitutes a BSA mass adsorption of about 1.77 μg/cm2 and is compared to literature values measured with other sensing platforms.