Patent ID: 7835870

Claim:
A system for evaluating the length of biopolymers in a sample, the system comprising: a memory storage for maintaining a database; and a processing unit coupled to the memory storage, wherein the processing unit is operative to: use a direct current stimulus to determine a direct current base length region corresponding to at least a portion of the sample, the direct current base length region appearing to correspond to biopolymers of only one length after the direct current stimulus is used; determine an initial value for at least one alternating current stimulus characteristic; use a combination stimulus comprising a combination of the direct current stimulus and an alternating current stimulus to determine that the direct current base length region corresponds to a first set of biopolymers and a second set of biopolymers, the first set of biopolymers having a first base length and the second set of biopolymers having a second base length, wherein the processing unit being operative to use the combination stimulus comprises the processing unit operative to iteratively optimize the at least one alternating current stimulus characteristic, starting with the determined initial value, to increase the sensitivity of the determined direct current base length region wherein the processing unit being operative to iteratively optimize comprises the processing unit being operative to iteratively adjust the alternating current stimulus characteristic from the determined initial value to increase a difference between a mean translocation time corresponding to the first set of biopolymers and a mean translocation time corresponding to the second set of biopolymers; use the at least one optimized alternating current stimulus characteristic value to determine a length of a biopolymer in the sample; and output the determined length of the biopolymer.