Time-resolved DNA-microarray reading by an intensified CCD for ultimate sensitivity

Abstract
We describe a novel technique for DNA-microarray reading based on time-resolved fluorescence measurements. We used an intensified CCD camera with picosecond resolution to acquire a set of time-delayed fluorescence images from a mutation DNA microarray marked with cyanine 3. We measured the fluorescence lifetimes of the marker and the background separately, and we used this information to calculate the amplitude map of the marker, starting from the time-delayed images. This procedure allowed us to identify hybridized spots that are not visible in fluorescence images acquired with continuous-wave detection.