Patent ID: 8067169
Filing Date: 2011-11-29
Classification: B82Y,C12Q,G01Q,Y10T

Abstract:
1. A method for distinguishing individual single-stranded DNA molecules from individual double-stranded DNA molecules, wherein said individual single-stranded DNA molecules and said individual double-stranded DNA molecules are disposed on discrete locations on a substrate, comprising the steps of: preparing a sample substrate having a gold surface with DNA molecules deposited thereon in discrete locations; vibrating a harmonic cantilever with a tip and obtaining a harmonic signal from said vibrating; contacting the vibrating harmonic cantilever tip with the sample substrate comprising said DNA molecules at said discrete locations; measuring changes in said harmonic signal at different sample DNA molecules in different discrete locations; and measuring changes in said harmonic signal in order to distinguish individual single-stranded DNA molecules from individual double-stranded DNA molecules, wherein said individual single-stranded DNA molecules and individual double-stranded DNA molecules produce harmonic signals that differ in one or both of amplitude and phase.