Extending Fluorescent Assays In Vivo for Biomedical Sensing: Wavelength Modulation Spectroscopy

A system and method of enhancing fluorescence assays can include signal modulation. In one aspect, a system for monitoring a sensor can include an excitation source directing a modulated excitation beam at a sensor, the modulated excitation beam having a modulation frequency, and a detector configured to monitor emission from the sensor, wherein the detector monitors emission at a multiple of the modulation frequency. In another aspect, a method of detecting an emission from a sensor can include irradiating a sensor with a modulated excitation beam having a modulation frequency, and detecting an emission from the sensor, wherein the detector monitors emission at a multiple of the modulation frequency.