Ultrafast lasers protect a DNA building block from destruction

An international research team led by DESY researcher Francesca Calegari and with the key participation of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) has demonstrated that ultrashort laser pulses can be used to protect one of the DNA building blocks against destruction induced by vacuum ultraviolet (VUV) radiation. The research group unveiled that a second laser flash in the infrared, timed shortly (only a few millionths of billions of a second) after the first VUV flash, prevented the adenine molecule to disintegrate, therefore stabilising it. The group presents their work in the journal Communications Chemistry published by Nature publishing group.

High energy radiation can cause irreparable damage to our own biological molecules – such as DNA – leading to mutations and potentially cell death. Damage is often occurring as a consequence of the molecular ionisation, inducing the fragmentation of the DNA subunits. So far, protection against radiation damage has hardly been achieved, as the photo-induced dissociation process could not be stopped. In their ultra-short-time experiments, Francesca Calegari´s research group and collaborators have discovered that, by taking advantage of mechanisms that take place on extremely fast time scales, it is indeed possible to protect the molecule.

Read more on the DESY website

image: Artist´s impression of the ultrafast stabilisation of adenine against dissociation: When the molecule is ionised by VUV radiation it undergoes dissociation, however, by taking advantage of a charge migration mechanism and by properly timing a second infrared laser pulse it is possible to stabilise it via a second ionisation event.

Credit: U. De Giovannini MPSD