1/fα noise in the dynamic force spectroscopy curves signals the occurrence of biorecognition.

Biorecognition leads to the formation of a specific complex between a couple of biological partners to accomplish a functional task. Its occurrence can be inferred a posteriori by analyzing the unbinding force curves in a dynamic force spectroscopy experiment. Because of nonspecific interactions, the method is not, however, exempt from ambiguities and subjectivity. A fingerprint of the partner recruitment in the complex has been disclosed in the fluctuations of the atomic force microscopy cantilever. We demonstrate that the formation of the biotin-avidin specific complex strongly correlates with a 1/f(α) noise in the force curve fluctuations.