Scientists from the Prof. Ki-Bum Lee's Lab (Yixiao Zhang and Hudifah Rabie) showcased an 808 nm NIR-mediated stem cell differentiation control system (UCNP@mSi@pSP) with abilities to trigger photo-isomerization of poly-spiropyran and achieving remote control of small molecule release [Scheme 1]. Moreover, the core-shell-shell structured UCNPs utilize spatial dopant separation to mitigate energy cross-relaxation and pinpoint the optimal composition allowing for efficient UV emissions using 808 nm NIR excitation. Specifically, this system includes: i) multi-shell UCNPs tailored for generating efficient UV emissions from 808 nm NIR excitations; ii) a photo-switching spiropyran-based polymer gating to generate an “on-off” releasing capability; iii) cell signaling molecules that can be released in a remotely controlled manner. Taking advantage of these unique properties, they utilized these upconversion nanoparticle constructs (UCNP@mSi@pSP) to control stem cell differentiation behaviors through 808 nm NIR excitations, demonstrating high biocompatibility and functional utility. This work was recently published in ACS Applied Materials & Interfaces (Zhang, Y. et al. 2020, doi.org/10.1021/acsami.0c10145). This is a collaboration work with Prof. Thomas Hirsch’s Lab (University of Regensburg).
Dr. KiBum Lee