  An efficient mass sensor based on exceptional points (EPs), engineered under
synthetic magnetism requirement, is proposed. The benchmark system consists of
an electromechanical (optomechanical) system where an electric (optical) field
is driving two mechanical resonators which are mechanically coupled through a
phase-dependent phonon-hopping. This phase induces series of EPs once it
matches the condition of $\frac{\pi}{2}(2n +1)$. For any perturbation of the
system, the phase-matched condition is no longer satisfied and this lifts the
EP-degeneracies leading to a frequency splitting that scales as the square root
of the perturbation strength, resulting in a giant sensitivity-factor
enhancement. Owing to the set of EPs, our proposal allows multiple sensing
scheme and performs better than its anti-PT-symmetric sensor counterpart. This
work sheds light on new platforms that can be used for mass sensing purposes,
opening up new opportunities in nanoparticles or pollutants detection, and to
water treatment.
