New strategies for low light level detection in single molecule spectroscopy

The use of low excitation intensities in single molecule experiments reduces photobleaching and background scatter. Under this condition, detection procedures, which utilize the measured information in an efficient way, should be developed. New statistical procedures based on the measurement of the distribution of the arrival times of the first and single detected photon during the detection interval are proposed. Using simulated data, we show that, for low numbers of detected photons, the new statistical procedures yield more reliable parameter estimates than the commonly used distribution of the number of detected photons per detection interval.