Molecularly Engineered Artificial Nanopores with Differential Selectivity and Sensitivity

University Of Texas At Arlington, Arlington TX

Investigators

Abstract

Objectives: This proposal addresses a number of fundamental and important obstacles that have limited the utility of nanopore sensing technology. Specifically, nanopore size, surface composition and stability of the pores are addressed to broaden this technology to include important new areas, e.g. sequencing of genomes, as but one of many examples. To help expedite progress in this area, our objective involves fabrication and thorough evaluation of a new approach to nanopore sensor technology. Specifically, we propose construction of artificial pores in which both the size and surface chemistry of the pores are precisely controlled over a wide range of pore sizes. For this purpose, a novel combination of thermal processing, followed by pulsed plasma chemical vapor deposition, will be used to shrink pore sizes controllably and reproducibly, while simultaneously varying surface chemistry. Availability of these molecularly engineered nanopores will hopefully overcome limitations currently encountered in analytical applications of this technology. An additional important objective involves extension of this technology to several new, high profile applications to be made available via our approach, e.g., selective differential detection by two oppositely chirally functionalized nanopores which will revolutionize chromatographic measurement of chiral compounds; similar schemes will be possible in many other cases. Intellectual Merits of the Proposed Activity? To date, nanopore fabrication has focused primarily on low-throughput serial approaches, with little use of bottom-up technology. In general, key issues such as stability of nanopore/fluid interfaces, reproducibility of nanopore surface properties, extended pore stability and the need for robust chemical functionalization of the nanopores remain. The ready availability of mechanically stable nanopores, having a range of well-defined diameters and surface chemistries, as described in this proposal, represents a transformative advance in this area. New insights will be gained from selective interactions in nanopores, providing quantitative handles to evaluate the molecular responses of ligands and to define novel, chemical means of interrogating targeted analytes. This will stimulate additional studies: control of translocation times of analytes through the pores (an immensely important present problem) and the use of chemistry and size differentiated nanopore arrays. This innovation will also help overcome and replace the present labor-intensive and low-throughput fabrication methods. Broader Impacts of the Proposed Activity? The proposed project will impact many areas that depend on the confluence of sciences and engineering. Examples include design of bio-inspired systems, sensors for environment and living systems, etc. The basic principles involved can be integrated into all levels of education. Graduate and undergraduate (UG) students will be engaged and introduced to exciting new dimensions of analytical chemistry, biochemistry and solid-state fabrication through development of a cross-listed course module on the bio-nano interface. The research outcomes will be also used to develop integrative participatory modules at our presently conducted Summer Camps (for middle/high-school students) and Girlgeneering Camps (for female high school students) to attract future adults to STEM careers. These outreach endeavors will be pursued: (1) Seminars/lab-tours for involvement and retention of UGs in research; (2) Engaging minority students through the McNair Fellows program; (3) Dynamic Facebook presence for the projection/exposure/discussion of the research; (4) Engagement of K-12 students and teachers through live webcasts. The results of the proposed research and education endeavors will be disseminated not only through peer-reviewed articles and conferences, but also through public media (radio, newspaper, weblogs, public displays). UTA Chemistry participates in the local State Fair. UTA has the largest digital planetarium in the Metroplex, with extremely heavy K-12 traffic. We plan to develop a small clip on nanopore sensors.