US Patent 7410564 - Biopolymer identification during translocation through nanopore

http://www.freepatentsonline.com/7410564.html

Nanopores are analytic devices used for single molecule sorting and DNA sequencing. This patent from Agilent Technologies teaches applying a ramping voltage to electrodes adjacent the nanopore to enhance the speed and efficiency of DNA sequencing. Claim 1 reads:

1. An apparatus for detecting a biopolymer in a nanopore, comprising:

(a) a first electrode;

(b) a second electrode adjacent to said first electrode;

(c) a nanopore adjacent to said first electrode and said second electrode and positioned to allow said biopolymer to be positioned between said first electrode and said second electrode; and

(d) potential means for electrically connecting said first electrode and said second electrode for applying a ramping voltage over an energy spectrum of the biopolymer from said first electrode, through a portion of said biopolymer in said nanopore, to said second electrode to produce a signal indicative of said portion of said biopolymer; wherein ramp-time of the applied voltage is short compared to a nucleotide translocation time through the nanopore.