Methods and systems for time-gated fluorescent-based detection

A method for detecting a presence or absence of an analyte in a solution, comprising:

• directing the solution to a device comprising a reaction chamber configured to receive the solution comprising the analyte, and further comprising a temperature control system capable of changing the temperature of the solution in the reaction chamber, wherein the reaction chamber comprises a probe that binds to the analyte, and further wherein the probe is labeled with a long-lifetime fluorophore;
• applying a time-varying temperature profile to the reaction chamber;
• applying an optical excitation pulse to the analyte within a first time period;
• detecting periodically a fluorescent signal from the reaction chamber during a second time period subsequent to the first time period, wherein the optical excitation pulse is not applied during the second time period;
• and
• wherein the signal is indicative of the presence or absence of the analyte.