Fig. 6
From: Synthetic protein-conductive membrane nanopores built with DNA
The flux of proteins through single DNA nanopores is modulated by antibodies. a Schematic illustration of the antibody recognition assay. Hexahistidine-tagged enhanced green fluorescent protein (His6EGFP) (1.0 µM, 27 kDa), Rhodamine B dextran (8.0 µM, 70 kDa), and α-His antibody (0.6 µM, 137 kDa) are sealed inside the chip cavities by supported lipid bilayer formation. After fluxing through the NP pore, His6EGFP is recognised by α-His antibodies and impeded to move back through the DNA nanopore. b Exemplary traces of His6EGFP (green square) and Rhodamine B dextran (70 kDa) (red circle) indicating that efflux of the fluorescent protein is impaired by the EGFP–antibody complex. c The results of the recognition assay with 1.1 nM NP are classified into pore-mediated EGFP effluxes, membrane ruptures, complex kinetics, and unsuitable controls without signal changes. d Schematic illustration of the antibody-sink experiment. Rhodamine B dextran (8.0 µM, 70 kDa) and α-His antibody (0.6 µM, 137 kDa) are encapsulated inside the chip cavities via supported lipid bilayer formation. After adding to the buffer reservoir His6EGFP (80 nM) and DNA nanopore (1.1 nM), free His6EGFP can diffuse via a DNA nanopore into the cavities where it is recognised and bound by α-His antibody. This leads to an accumulating green fluorescence signal until all antibodies are saturated with fluorescent proteins. e Normalised mean grey values of His6EGFP (green square) and Rhodamine B dextran (70 kDa) (red circle) showing accumulation over time for a single cavity, mediated by the antibody sink reaction. f Statistical histogram analysis of 208 kefflux constants for the antibody-sink experiment. Source data are provided as a Source Data file
