Charge-sensitive optical detection of binding kinetics between phage displayed peptide ligands and protein targets

Abstract

Provided herein are systems for the label-free detection of target molecules in samples. The systems include a sensor probe positioned in a sensing region and configured to bind to receptors for the target molecules. The systems also include electrodes configured to expose the sensor probe to an alternating electric field, and a light source optically coupled to the sensor probe and configured to provide light along a length of the sensor probe. In addition, the systems also include a position sensitive photodetector configured to detect a position of light exiting the sensor probe, and a processor configured to assess, based at least in part on the position of the light exiting the sensor probe, an amplitude of oscillation of the sensor at a frequency of the alternating electric field and a direction of a displacement of the sensor. Additional systems and related methods are also provided.