Sensing Base Modifications in Non-Canonically Folded DNA with an Optimized Host:Guest Sensing Array

An arrayed host:guest fluorescence sensor system can discriminate DNA G-quadruplex structures that differ only in the presence of single oxidation or methylation modification in the guanine base. These small modifications make subtle changes to G4 folding that are often not detectable by CD but induce differential fluorescence responses in the array. The sensing is functional in diluted serum and is capable of distinguishing individual modifications in DNA mixtures, providing a powerful method of detecting folding changes caused by DNA damage.