| Abstract
| - We present a simple, cost-effective design for amplifyingoligodeoxynucleotide (ODN) sensing, in microliter ODNvolumes containing copper ions, by solution streaming(bubbling). The inert gas streaming (bubbling) at a constant pressure of 0.04 bar drives the motion of a 30-μLODN droplet containing a three-electrode circuit (inverteddrop microcell), and in the presence of copper ions offersan ∼50-times improvement in the detection of ODNsamples. The detection of ODNs at the carbon pasteelectrode is based on the enhancement of the oxidationpeaks of purine bases (adenine and guanine) by theanodic stripping of the electrochemically accumulatedcomplex of Cu(I) with purine base residues of acidhydrolyzed ODN samples (Cu(I)−ahODN complex). Weused the proposed method for (i) the determination of thepercentage content of adenine and guanine units withinanalyzed ODN samples at subnanomolar concentrations(related to monomer content) and (ii) the detection of the(TTC)n triplet expansion using magnetic DNA hybridization with reporter probes containing guanine units (theTTC trinucleotide repeat expansion is associated withserious hereditary diseases, including Friedreich ataxia).
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