  We present a proof-of-principle study of superconducting single photon
detectors (SSPD) for the detection of individual neutral
molecules/nanoparticles at low energies. The new detector is applied to
characterize a laser desorption source for biomolecules and it allows to
retrieve the arrival time distribution of a pulsed molecular beam containing
the amino acid tryptophan, the polypeptide gramicidin as well as insulin,
myoglobin and hemoglobin. We discuss the experimental evidence that the
detector is actually sensitive to isolated neutral particles.
