Single molecule hydrodynamic separation for ultrasensitive and quantitative dna size separations

This paper presents a high sensitivity and low-reagent consumption molecular sizing and separation strategy. Through the integration of Hydrodynamic Separation and Cylindrical Illumination Confocal Spectroscopy, we achieve molecular separation over a large dynamic range with high sensitivity and resolution. The wide range and high sizing resolution was demonstrated by separating both large (23 vs. 27 kbp) and small (50 vs. 100 bp) DNA under identical conditions. Separations were successfully performed with minimal sample consumption, using as little as 1 pL of sample and detecting as few as 9 molecules of one DNA fragment, suggesting a sensitivity unmatched by conventional methods.