Fig. 1. Aerolysin reading of polymers encoding single-bit information.

(A) Illustration of single-channel recording setup using an aerolysin pore; the cis and trans chambers are filled with 1.0 M KCl electrolyte buffer, and voltage is applied across the pore using two Ag/AgCl electrodes. Amino acid at 220 and 238 position are highlighted by red and blue, respectively. (B) Schematic structure of two representative polymers: AA00000AA and AA00100AA. (C) Raw current trace of AA00000AA during single-channel recording measurement (top). Magnification of one single event (bottom). (D) Raw current trace of AA00100AA measurement. Magnification of one single event (bottom) showing a multilevel signal: L-1 (gray), L-2 (orange), L-3 (green), L-4 (orange), and L-5 (gray). (E) I/I₀ histogram (top) and dwell time distribution (bottom) for L-1, L-2, L-3, L-4, and L-5, respectively. Relative fitted values are reported in each figure. All data were obtained using 1.0 M KCl, 10 mM tris, and 1.0 mM EDTA at pH 7.4, applying a bias potential of 100 mV.