Nanosecond fluorescence lifetime low-cost sensor

A novel nanosecond fluorescence lifetime low-cost system have been developed combining the most advanced optoelectronic and RF semiconductor technologies with LTCC (Low Temperature Co-fired Ceramic) microfluidic integrated systems. The lifetime measurement is done by phase-modulation technique, which uses sine-modulated light source and calculates the lifetime measuring the phase between emission and fluorescence. The modulation frequency determines the minimum lifetime, so to measure nanosecond lifetimes, the modulation frequency has to be over 100MHz. The performance of the sensor has been tested with a fluorescent dye. The used dye fluorescence lifetime, 2.44ns, was measured by commercial equipment and matches with the lifetime obtained by our system. In addition, the sensor shows a fast response to variations in the fluorescence lifetime due to fluorescence quenching in the presence of Cu²⁺.