Highly Efficient Single Molecule Detection in Different Micro and submicrometer Channels with cw-excitation

In this article we describe a detailed comparison between single molecule detection in three different types of microchannels. The overall detection efficiencies and the signal-to-noise ratios are compared. A new data evaluation technique that is used is explained in detail. The average number of photons per molecule is calculated from the measurements and the detection properties of each channel with respect to the diffusional characteristics of the dye molecules are investigated. From the detection efficiencies advantages and drawbacks of the individual methods are elucidated as well as possible applications of the techniques are illustrated.