Heat transfer resistance as a tool to quantify hybridization efficiency of DNA on a nanocrystalline diamond surface

• Hybridization was done using different concentrations of target DNA.
• Dose–response curves: DNA concentration versus change in thermal resistance
• Heat-transfer analysis as a quantitative DNA detection tool
• Possibility for hybridization efficiency analysis

In this article, we report on a label-free real-time method based on heat transfer resistivity for thermal monitoring of DNA denaturation and its potential to quantify DNA fragments with a specific sequence of interest. Probe DNA, consisting of a 36-mer fragment was covalently immobilized on a nanocrystalline diamond surface, created by chemical vapor deposition on a silicon substrate. Various concentrations of full matched 29-mer target DNA fragments were hybridized with this probe DNA. We observed that the change in heat transfer resistance upon denaturation depends on the concentration of target DNA used during the hybridization, which allowed us to determine the dose–response curve. Therefore, these results illustrate the potential of this technique to quantify the concentration of a specific DNA fragment and to quantify the hybridization efficiency to its probe.