Calorimetric study of melted DNA glass

Jessica Valle-Orero, Jean-Luc Garden, Jacques Richard, Andrew Wildes, Michel Peyrard
In this work we report a detailed calorimetric study using differential scanning calorimetry (DSC) of the glassy behaviour of films made from DNA fibers. We show that after the first irreversible thermal denaturation of the molecules when the sample is reiteratively heated, it reaches a disordered state in which it presents a typical glass behaviour during successive cooling and heating scans. Furthermore, we have investigated the properties of these DNA films in two series of experiments, a
more » ... f experiments, a slow cooling at different rates followed by a DSC scan upon heating, and ageing at a temperature below the glass transition. Introducing the fictive temperature to characterise the glass allows us to derive quantitative information on the relaxations of the DNA films, in particular to evaluate their enthalpy barrier. A comparison with similar ageing studies on PVAc highlights some specificities of the DNA samples.
doi:10.1063/1.4794676 fatcat:v2auqmuvkvhm5agqtwsmhnsvia