Figure 2.

After loading cell lysate (frames A), the polarity is reversed to advance a depletion front to the right against a flow to the left (frames B). The depletion front advancement is arrested by the flow at a particular position (Reproduced with permission from the Annu. Rev. Anal. Chem., Volume 7 © 2014 by Annual Reviews, http://www.annualreviews.org). Gel electrophoresis (second non-ladder lanes of D and E) and SDS-PAGE (second lane of C) analyses of the trapped lysate at the boundary of the depletion front shows only high-mobility microRNA remains. Longer nucleic acids and all proteins evident in the first unfiltered lysate lane have been removed. Experiment E is to verify the trapped molecules are microRNAs and other short RNAs (Reproduced from [3] with permission).