Publications

Voltage-gated protein transport through nanoporous membranes

Hatch, Anson V.; Singh, Anup K.

We report a novel means of fractionating proteins based on their voltage-dependent electromigration through nanopores of a polymer membrane. The nanoporous membranes were fabricated in situ in channels of a microchip using photopolymerization. The pores (1-10 nm) are small enough that proteins are excluded from passage with low applied electric fields, but increasing the field enables proteins to pass through. The magnitude of field required for a change in exclusion behavior is protein-specific with a correlation to protein size. Passage of proteins through the pores at higher field strengths could be attributed to partial unfolding or deformation of proteins due to the driving force of the applied field. The field-dependent exclusion mechanism could be useful as a multifaceted fractionation tool with single membranes or a network of membranes. Another exciting possibility is characterizing protein conformation, folding and stability based on field-dependent transport through nanopores. © 2006 Society for Chemistry and Micro-Nano Systems.