Controlled tunnel gap device for sequencing polymers
The invention includes compositions, devices, and methods for analyzing a polymer and/or polymer unit. The polymer may be a homo or hetero-polymer such as DNA, RNA, a polysaccharide, or a peptide. The device includes electrodes that form a tunnel gap through which the polymer can pass. The electrodes are functionalized with a reagent attached thereto, and the reagent is capable of forming a transient bond to a polymer unit. When the transient bond forms between the reagent and the unit, a detectable signal is generated and used to analyze the polymer.
1. A method of analyzing a polymer or polymer unit, the method comprising:
a) forming a transient bond between a unit of the polymer and a first electrode functionalized with a first reagent and between the unit of the polymer and a second electrode functionalized with a second reagent, wherein the first reagent and the second reagent are the same; and
b) detecting a detectable signal when the transient bonds form.
2. The method of claim 1 , wherein the first reagent and the second reagent are selected from the group consisting of mercaptobenzoic acid, 4-mercaptobenzcarbamide, imidazole-2-carboxide, and 4-carbamonylphenyldithiocarbamate.
3. The method of claim 1 , wherein the polymer is DNA or RNA and the polymer unit is a nucleotide.
4. A method of sequencing a polymer, the method comprising
a) allowing a unit of the polymer to flow into a tunnel gap formed between a first electrode functionalized with a first reagent and a second electrode functionalized with a second reagent, wherein the first reagent and the second reagent are the same;
b) forming a transient bond between a unit of the polymer and the first and second reagents;
c) detecting a detectable signal when the transient bonds forms; and
d) repeating steps a)-c) for each sequential unit of the polymer.