123rd General Meeting of the KCS

Type Symposium
Area Controlling Properties of Organic/inorganic Materials for Optoelectronic Devices
Room No. Room 405+406
Time FRI 10:25-10:50
Code MAT2-4
Subject TTA-based Upconversion: Principle and Biophotonic Applications
Authors Jaehyuk Kim
Department of Chemical and Environmental Engineering, Pusan National University, Korea
Abstract Upconversion (UC) refers to a photon-frequency amplification process in which the energy absorbed by UC media from two or more incident photons is combined and one photon with higher energy is subsequently emitted, resulting in an anti-Stokes shift. In this presentation, some introductory stories about TTA-UC including basics of the photon energy, mechanisms involved in TTA-UC, achievement and limitation of previous researches will be given first. Then the latest development in our lab – novel vehicle for UC-oil laden hollow mesoporous silica and its biophotonic applications – will be introduced. The details are as bellows:
A recyclable, aqueous-phase functioning, and biocompatible photon upconverting system is developed. Hollow mesoporous silica microcapsules (HMSMs) with ordered radial mesochannels were employed, for the first time, as vehicles for the post-encapsulation of oil-phase triplet-triplet annihilation upconversion (TTA-UC), capable of homogeneous suspension in water. In-depth characterization of such upconverting oil-laden HMSMs (UC-HMSMs) showed that the mesoporous silica shells reversibly stabilized the encapsulated UC oil in water to allow efficient upconverted emission, even under aerated conditions. In addition, due to the lipophilic nature of the encapsulated UC oil, UC-HMSMs were found to be actively bound on the surface of human mesenchymal stem cells (hMSCs) without significant cytotoxicity, providing a new concept for integrating TTA-UC and stem-cell therapy. These findings reveal the great promise of UC-HMSMs to serve as ideal vehicles not only for ultralow-power in vivo imaging but also for stem cell labeling to facilitate the tracking of tumor cells in animal models.
E-mail jaehyuk.kim@pusan.ac.kr