Fabrication Of Small-Scale Nanochannels And Preliminary Study Of Ion Migration

Ion channels play a huge role in cells and organisms.The study of ion migration rules in ion channels is helpful to explore the specific processes and principles of various life activities of cells and organisms.It is also of great significance for the development of pharmacology and new drugs.Nanopore sensing technology can detect the electrical changes of ions through the translocation of nanochannels.This topic studies the fabrication of small-scale nanochannels to mimic ion channels,and makes a preliminary inquiry into the migration rule of ions in the channels.The main research contents are as follows:1)Research on key technologies for fabricating small-scale nanochannels.Based on the principle of dielectric breakdown,the existing experimental materials and instruments were used to build a nanochannels fabrication platform.Lab VIEW was used as a programming tool to develop a software control system,and the experimental operation steps and requirements were improved.Finally,the characterization methods of small-scale nanochannels were explored.2)Explore the nanochannels fabricating process of SiN film chip thinned by ion beam.For the SiN film chip thinned by the ion beam,the small-scale nanochannels fabricating process based on the principle of dielectric breakdown was studied,and a software control system based on Lab VIEW was developed.Then,the algorithm was improved and the parameters were adjusted according to the experimental results,and small-scale nanochannels around 5 nm were fabricated and characterized.The effects of SiN film leakage current on the fabrication time and the size of nanochannels were studied.3)Explore the nanochannels preparation process of SiN film chip thinned by chemical etching and graphene film chip.The fabrication process of small-scale nanochannels was studied for SiN film chips thinned by chemical etching and graphene film chips,and a fabricating control system was developed to fabricate and characterize small-scale nanochannels below 3 nm.Subsequently,the influences of the hydrophilicity of the SiN membrane and the voltage on the fabricating time and the size of the fabricated nanochannels were studied.4)Research experiment of ion migration in the channel.KCl electrolyte solutions with different concentrations were prepared.After preparing small-scale nanochannels with a pore diameter of less than 3 nm,switch to different concentrations of KCl solution and apply bias voltages of different sizes.The ion channel acquisition and recording system were used to detect and collect ions in the solution through the nanochannels.Based on the current signal,the migration of ions in the channel was preliminary studied.