Electrolyte chemistry plays an important role in the transport properties of analytes through nanopores. Here, we report the translocation properties of the protein human serum transferrin (hSTf) in asymmetric LiCl salt concentrations with either positive (
In this work, we present a step‐by‐step workflow for the fabrication of 2D hexagonal boron nitride (h‐BN) nanopores which are then used to sense holo‐human serum transferrin (hSTf) protein at pH ∼8 under applied voltages ranging from +100 mV to +800 mV. 2D nanopores are often used for DNA, however, there is a great void in the literature for single‐molecule protein sensing and this, to the best of our knowledge, is the first time where h‐BN—a material with large band‐gap, low dielectric constant, reduced parasitic capacitance and minimal charge transfer induced noise—is used for protein profiling. The corresponding Δ
- NSF-PAR ID:
- 10457793
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ELECTROPHORESIS
- Volume:
- 41
- Issue:
- 7-8
- ISSN:
- 0173-0835
- Page Range / eLocation ID:
- p. 630-637
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Ctrans /Ccis < 1) or negative chemical gradients (Ctrans /Ccis > 1). Thecis side concentration was fixed at 4 M for positive chemical gradients and at 0.5 M LiCl for negative chemical gradients, while thetrans side concentration varied between 0.5 to 4 M which resulted in six different configurations, respectively, for both positive and negative gradient types. For positive chemical gradient conditions, translocations were observed in all six configurations for at least one voltage polarity whereas with negative gradient conditions, dead concentrations where no events at either polarity were observed. The flux of Li+and Cl−ions and their resultant cation or anion enrichment zones, as well as the interplay of electrophoretic and electroosmotic transport directions, would determine whether hSTf can traverse across the pore. -
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