A biosensor, a method of making a biosensor, and a method of using a biosensor are described. A biosensor includes a transducer and a peptide encoding the most probable binding domain of an olfactory receptor protein. In embodiments, the transducer is a piezoelectric crystal. The method of making a biosensor includes modeling the three dimensional structure of an olfactory receptor protein; identifying the most probable binding domain of an olfactory receptor protein using a protein docking program; synthesizing a peptide encoding the most probable binding domains or a part thereof; and attaching the peptide to a transducer.