Development of novel near-infrared persistent phosphors for bio-imaging

开发用于生物成像的新型近红外持久荧光粉

基本信息

批准号：
18F18051
负责人：
田部勢津久
金额：
$ 1.92万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for JSPS Fellows
财政年份：
2018
资助国家：
日本
起止时间：
2018-04-25 至 2020-03-31
项目状态：
已结题

项目摘要

In this year, the subject is composed of two parts: (i) Optical probes for excitation-free brain imaging; (ii) Ceramic persistent phosphors toward efficient flicker suppression in alternating current (AC)-wLEDs. For (i), Fluorescence based optical imaging using NIR light is a noninvasive imaging technique, which possesses the possibility to acquire real-time data at a high speed, and allows for the time-resolved detection of in vivo dynamic processes with high spatial and temporal resolution. The wavelength region longer than 1.0um in SWIR; the 2nd (NIR-II, 1.0-1.35um) and 3rd (NIR-III, 1.5-1.8um) windows, is highly advantageous over the shorter NIR-I one because of lower scattering coefficient result in improved contrast quality, higher spatial resolution. Inspired by the energy levels of lanthanoid and transition metal ions in host matrix like garnets or perovskites, we realized long persistent luminescence (over 10 hours after ceasing external excitation) in the NIR-III window utilizing the persistent energy transfer from Cr3+ to Er3+ in GAGG garnet structure, and Cr3+ to Nd3+ LaAlO3 perovskite structure in the NIR-II window. For (ii), based on the research result in garnet-based persistent phosphors, by modifying the Ga3+ substitution in Ce3+-Cr3+ co-doped GAGG garnets, yellow persistent phosphors have been fabricated able to generate intense initial persistent luminescence to suppress the flicker effect of AC-driven LEDs. The best sample exhibits obvious flicker suppression, with flicker ~26.15% and index ~0.07 for the sinusoidal waveform.

今年的课题由两部分组成：（i）用于无激励脑成像的光学探针； (ii) 陶瓷持久性荧光粉可有效抑制交流 (AC)-wLED 中的闪烁。对于（i），使用近红外光的基于荧光的光学成像是一种非侵入性成像技术，它具有高速获取实时数据的可能性，并且允许对具有高空间和分辨率的体内动态过程进行时间分辨检测。时间分辨率。 SWIR中大于1.0um的波长区域；第二个（NIR-II，1.0-1.35um）和第三个（NIR-III，1.5-1.8um）窗口比较短的 NIR-I 窗口更具优势，因为较低的散射系数可提高对比度质量，提高空间分辨率。受到石榴石或钙钛矿等基质中镧系元素和过渡金属离子能级的启发，我们利用 GAGG 中从 Cr3+ 到 Er3+ 的持续能量转移，在 NIR-III 窗口中实现了长持续发光（停止外部激发后超过 10 小时） NIR-II 窗口中的石榴石结构和 Cr3+ 至 Nd3+ LaAlO3 钙钛矿结构。 (ii)基于石榴石基持久荧光粉的研究成果，通过改变Ce3+-Cr3+共掺GAGG石榴石中Ga3+的取代，制备出能够产生强烈初始持久发光以抑制闪烁效应的黄色持久荧光粉交流驱动 LED。最好的样本表现出明显的闪烁抑制，正弦波形的闪烁约为 26.15%，指数约为 0.07。