Nanopore-mediated electric detection of ions, nanoparticles and DNA

On my first year, I focused my activity on the synthesis of heterostructured nanocrystals based on single and double perovskites. Since these nanostructures were based on Metal, lead and Halide ions, the idea behind this project was to enhance the stability of the materials, decrease their toxicity and combine their photocatalytic activities. During my last two years, I dedicated my attention to a new project, whose core idea was to exploit nanopores as sensing probes for DNA and nanoparticles: NPs. The rationale behind this project was to use NPs decorated DNA as a data storage medium, because of its compact dimensions, high information storage density and low costs. For this purpose, my activities were centered on three main topics. The first one was to study how the type of nanopore that would be used could influence the translocations, thus the reading, of NanoParticles and of DNA, which are the core of NPs decorated DNA data storage. For this reason, it was essential to understand the electrical properties of the nanopores and their Ion Current Rectification, ICR, behavior. Indeed, ICR is a physical phenomenon that can cause a nanopore to transport ions more efficiently in one direction than in the opposite. Therefore, ICR would influence also the movement of any charged entity, as NPs or DNA. To evaluate ICR effects on nanopores, I studied four types of them, and I tested each one of them with six electrolytes from the Hofmeister series. I could conclude that nanopores’ ICR behavior depended on surface charge distribution, aspect ratio and used electrolytes. For these reasons, the aspect ratio of our nanopores was at the center of my following activities. Indeed, in my second project, I was able to demonstrate that if the nanopores were shaped as conical nanoantennas, this affected their ICR properties. Finally, in my third project, I studied the role of cylindrical shape in a nanoantenna, NA, pore, in regard of its ability to read translocation of NPs and DNA, achieving the reading of the both of them.