Biological and synthetic pores and channels of nanoscale dimensions display unique ionic and protein transport behavior. Nanopores modified with supramolecular chemical species (such as polyelectrolyte brushes) have dimensions that are similar to the range of the electrostatic interactions, and also to the molecular size of the tethered macromolecules. In cells, Nuclear Pore Complexes (NPC) control the transport of species between the cytoplasm and the nucleus using disordered proteins as gate keepers. The competition between molecular and interaction length scales, as well as the geometry of the surfaces, creates interesting possibilities for the creation of stimuli responsive gates and ion channels and for the fundamental understanding of the interplay between molecular organization, charge, proteins and nanoparticle transport in nanoconfined environments. The proposed work involves the development and application of theoretical approaches that capture the coupling between molecular organization, physical interactions and chemical equilibrium in order to describe the behavior of the nanopores. Most of the theoretical work will be based on an equilibrium and kinetic molecular theory that has been developed in the group of the PI. Furthermore, comparing the predictions of the molecular theory with detailed molecular dynamics simulations (when possible) will check the range of applicability of the theory. The proposed work is separated into two main thrusts: 1) Synthetic nanopores. Understanding how responsive polymers, bulk solution conditions and the geometry of the nanopore affect the structure and transport of nanoparticles, proteins and small ions through the nanopores. The types of responsive polymers include: weak polyelectrolytes, hydrophobic polymers and pH sensitive zwitterionic polymers. 2) Nuclear Pore Complex. Systematic studies of the role that intrinsic proteins forming the NPC as well as adsorbed proteins have on the ability of the pores to gate transport of proteins across the pore. The proposed work is of fundamental importance in the understanding of interfacial properties of responsible materials as well as transport. Moreover, the proposed work will provide guidelines for the design of nanoconfined soft materials with a wide range of applications in biosensing, charge or proteins separations, chromatography, drug delivery and microfluidics among others.
|Effective start/end date||7/1/14 → 6/30/18|
- National Science Foundation (CBET-1403058)