Characterization of protein unfolding with solid-state nanopores

In this work,we review the process of protein unfolding characterized by a solid-state nanopore based device. the occupied or excluded volume of a protein molecule in a nanopore depends on the protein's conformation or shape. a folded protein has a larger excluded volume in a nanopore thus it blocks more ionic current flow than its unfolded form and produces a greater current blockage amplitude. the time duration a protein stays in a pore also depends on the protein's folding state. we use bovine serum albumin (bsa) as a model protein to discuss this current blockage amplitude and the time duration associated with the protein unfolding process. bsa molecules were measured in folded,partially unfolded,and completely unfolded conformations in solid-state nanopores. we discuss experimental results,data analysis,and theoretical considerations of bsa protein unfolding measured with silicon nitride nanopores. we show this nanopore method is capable of characterizing a protein's unfolding process at single molecule level. problems and future studies in characterization of protein unfolding using a solid-state nanopore device will also be discussed. © 2014 bentham science publishers.