Multifunctional rare earth ions-doped Ba2LaF7 nanocrystals for simultaneous temperature sensing and photothermal therapy

As an urgent problem, cancer has boosted the development and application of many treatment technologies in biomedicine. Photothermal therapy with precise control for tumors has gained more and more attention as a promising technology in biomedical fields. In this work, rare earth ions-doped Ba2LaF7 nanocrystals have been successfully developed by the high-temperature solid-phase method as the core material in a multi-functional system. Optical temperature measurement based on fluorescence intensity ratio improves sensitivity by widely separating Er3+ and Nd3+ emission bands. Meanwhile, the relative sensitivity increases with increasing temperature. From the comparison between the fitting curve and the actual temperature, it can be concluded that the nanocrystals have a good photothermal response to the laser pumping power and can even be used for photothermal imaging. On this basis, to study its optical measurement and photothermal conversion performance, we made a multifunctional system acting on biological tissues. The results suggest that the developed material has a potential application in bio-targeted photothermal therapy.