EAGER: Layered Semiconductor Membranes for Tunable Separation and Filtering of Ions and Biomolecules

Clarkson University, Potsdam NY

Investigators

Abstract

The objective of the proposed EAGER research is to show the feasibility of using layered nanoporous semiconductor membranes for tunable ion and protein separation and filtering. This objective will be achieved through the use of complex computational models which have been previously utilized by the PI to describe electrostatic behavior of nanoporous semiconductor membranes, including layered membranes under bias, as tunable electronic devices for ion and biomolecular manipulations. This work is built on the widely known electrical tunability of semiconductor materials and the charge inversion phenomenon in the nanoporous semiconductor membranes under electrical bias, which was recently demonstrated by the PI. The novelty of the proposed membranes is in utilization of opposite doping in the layering of the n- and p-doped semiconductor materials to form a p-n junction membrane for versatile electric control over electrostatic potential landscape in the nanopores transversing the membrane. The intellectual merit of this program is developing self-consistent model of a nanoporous membrane composed of semiconductor materials and immersed in an electrolyte solution with electric bias applied to the semiconductor layers and the electrolyte solution, resulting in motion of ions in the solution through the nanopore. This model will be used to understand and control the membrane behavior with applications in ion separation and filtering. The advantage of using semiconductor materials for the membrane resides in the electrical tunability of these materials as well as ease of integration of such membrane in lab-on-a-chip and nanofluidic devices. Thus, the theoretical understanding of the effect of the ionic charge inversion in a nanopore in various semiconductor membranes and its influence on ionic transport through the nanopores could find broad applications in nanotechnology and bioengineering and will contribute to understanding analogous processes in biological and bio-mimetic systems. The primary goal of this focused program is to show the feasibility of using layered membranes made of doped semiconductor materials for separation and filtering of ions. The model developed as a result of this program will be further utilized for simulation of the electrically tunable membrane and electrolyte solution with a coarse-grained Brownian dynamics model of a biomolecule immersed in this solution. This project will stimulate future research on the effect of the membrane electrostatic potential over ionic and biomolecular movement through the pore with the main goal to demonstrate tunable control of the membrane for application in protein and biomolecule separation, concentration and filtering. The broader impact of this program is in directly addressing the need for developing new technologies for separation and filtering of biomolecules. The emergence of tunable protein and ion filters will have a beneficial impact on industry, research and society by broadening the application of a unified device towards multiple means and ease of integration with silicon-based technology in lab-on-a-chip and micro- and nanofluidic devices. Thus, an important aim of the program will be to establish a collaboration with an experimental group with expertise in the fields of membrane technologies or separation techniques to secure further testing and implemantation of the proposed ideas and methods in practice. This project will support two graduate students at Clarkson University (CU). International collaboration with the Moscow State University (MSU) will be strengthened by offering two summer positions to its undergraduate students for research projects within the framework of the program. A summer research position will be offered to a disabled undergraduate student at CU, and another summer position will be offered to a student outside of CU. The results of this program will be published in top journals and will be presented at national and international conferences. The PI will also maintain a research web-site to insure a wider public access to the results. The developed models will enrich the Computer Modeling in Physics course at CU which is offered by the PI every semester.