Katsonis was born in Vienna. She grew up in Orsay, in Paris Region. She is half French and half Greek. She studied chemical engineering at the Chimie ParisTech, before moving to Ecole Normal Superieure for her graduate studies with Ludovic Jullien. Katsonis earned her doctoral degree at the Pierre and Marie Curie University. She worked on nanoscale probes of two dimensional molecular self-assemblies with Denis Fichou. She joined the research group of Ben Feringa at the University of Groningen, where she worked on self-assembly of motors and switches. Whilst at Groningen Katsonis developed scanning probe microscopy for the determination of molecular chirality.