Self-Assembled Nanoparticle-Surfactant Bilayers: A Platform for Memristive Behavior and Ion Selectivity

We present a novel droplet interface bilayer (DIB) system stabilized by nanoparticle-surfactants (NPSs), which overcomes the stability and functionality limitations of traditional lipid and polymer bilayers^{[1, 2]}. Our NPS-based bilayers form densely packed monolayers at the liquid–liquid interface, preventing coalescence and enabling the formation of long-lived bilayers with tunable properties. Moreover, the NPS-DIB system enables selective ion/ molecules/nanoparticles transport through self-assembled nanochannels, formed by packing defects, exhibiting transport properties that depend on both charge and size. Our work also highlights the memristive behavior of these NPS-DIBs, where voltage-dependent ion distribution and nanochannel formation leads to short-term and long-term synaptic plasticity, mimicking biological neural networks. This system shows potential for applications in neuromorphic computing and nanofluidics. By tuning the packing density and external stimulus, we achieve control over the nanochannel size, ion selectivity, and transport properties. The robust stability and versatile functionality of this system make it a promising platform for future applications in bioelectronics, synthetic biology, and nanoelectronics.

[1] C. C. M. Sproncken et al., Nature 630, 866 (2024).

[2] E. B. Stephenson, J. L. Korner, and K. S. Elvira, Nature chemistry 14, 862 (2022).