Fig. 3.

(a) Aerolysin inserted into the lipid bilayer from the cis chamber. The ssDNA oligomers were added into the cis solution after applying a positive potential from the trans side. With the cis solution grounded, the negatively charged ssDNA was able to traverse the aerolysin from the cis to the trans chamber and induce a blockade current signal. (b) Single-channel recording of CA₃ (red), TA₃ (orange), AA₃ (green), and GA₃ (blue), and the corresponding typical current traces. (c) The residual current histograms (top) and scatter plots (bottom) of the duration versus residual current of CA₃, TA₃, AA₃, and GA₃, respectively. All residual current histograms were fitted to Gaussian distributions. (d) Durations recorded for the additions of CA₃, TA₃, AA₃, and GA₃ into the aerolysin nanopore, respectively. Reprinted with permission from DOI: 10.1002/smll.201702011, Small, 2017. (e) Detection of methylated and unmethylated DNA in serum. Upper panel: Preparation of serum samples. Human serum was centrifuged, apportioned, and stored at −20 °C before usage. Lower panel: Assignments of C-DNA (blue) and mC-DNA (red) in raw current traces. Two colored short lines and marks were assigned to C-DNA and mC-DNA, respectively. Reprinted with permission from DOI: 10.1021/acs.analchem.7b03133, Anal. Chem., 2017.