Theranostics is an interdisciplinary research field that combines “therapy” and “diagnostic” as a single approach towards more advanced and personalized medicine solutions. Despite the huge progress in this field in the last 20 years, there are still a lot of opportunities for improvement. In this context, cancer is known to cause local temperature variations in the body. Using a theranostic systems, one could localize a patient’s tumor using temperature while simultaneously triggering the release of a tumor drug. The goal of this project is to develop multifunctional hybrid lanthanide (Ln)-based nanomaterials with heating, drug delivery and photodynamic therapy