Pr<sup>3+</sup> doped NaYF<sub>4</sub> and LiYF<sub>4</sub> nanocrystals combining visible-to-UVC upconversion and NIR-to-NIR-II downconversion luminescence emissions for biomedical applications
Min Ying Tsang, Patryk Fałat, Magda A. Antoniak, Roman Ziniuk, Szymon J. Zelewski, Marek Samoć, Marcin Nyk, Junle Qu, Tymish Y. Ohulchanskyy, Dominika Wawrzyńczyk
Abstract
irradiation by light in the UVC range). A possibility of the latter was demonstrated by the denaturation of double-stranded DNA (dsDNA) into single-stranded ones that was caused by the UVC UCL emission from the NCs under 447 nm irradiation; it was evidenced by the hyperchromicity observed in the irradiated dsDNA solution and also by a fluorometric analysis of DNA unwinding (FADU) assay. Concurrently, the possibility of NIR-II luminescence bioimaging through biological tissues (bovine tooth and chicken flesh) was demonstrated. The proposed concept paves a way for NIR-II imaging guided antimicrobial phototherapy using lanthanide-doped fluoride nanocrystals.