The crossing takes place over six days on the Atacama Desert, the highest and driest desert in the world.
‘While I have run a couple of marathons in the past, this is something on a scale I would have never even considered, until urged on by an equally crazy friend,' she said.
‘The biggest challenge will be getting up every morning, no matter how tired I am and how sore and blistered my feet are, putting my pack on and running off again.'
Dr Zakrewski is raising money for Marie Curie and can be sponsored via her Justgiving page.