Langmuir, Vol.17, No.17, 5134-5136, 2001
Probing of DNA and single-base mismatches by chemical force microscopy using peptide nucleic acid-modified sensing tips and functionalized surfaces
DNA hybridization to peptide nucleic acid (PNA)-functionalized Au-coated tips is characterized by probing the force interactions between the PNA-functionalized tip or the DNA/PNA-functionalized tip with a hydrophobic 1-mercaptoundecane-modified Au surface, using chemical force microscopy (CFM). DNA concentrations as low as 3 x 10(-13) M can be detected by probing the respective force interactions. The CFM method is sufficiently sensitive to detect a single base mismatch,in the analyte DNA.