State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China.
State Key Laboratory of Metal Matrix Composites, Frontiers Science Centre for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.
Nat Commun. 2023 Feb 14;14(1):827. doi: 10.1038/s41467-023-36510-3.
Distinctive upconversion or downshifting of lanthanide nanocrystals holds promise for biomedical and photonic applications. However, either process requires high-energy lasers at discrete wavelengths for excitation. Here we demonstrate that co-sensitization can break this limitation with ultrawide excitation bands. We achieve co-sensitization by employing Nd and Ho as the co-sensitizers with complementary absorptions from the ultraviolet to infrared region. Symmetric penta-layer core-shell nanostructure enables tunable fluorescence in the visible and the second near-infrared window when incorporating different activators (Er, Ho, Pr, and Tm). Transient spectra confirm the directional energy transfer from sensitizers to activators through the bridge of Yb. We validate the features of the nanocrystals for low-powered white light-emitting diode-mediated whole-body angiography of mice with a signal-to-noise ratio of 12.3 and excitation-regulated encryption. This co-sensitization strategy paves a new way in lanthanide nanocrystals for multidirectional photon conversion manipulation and excitation-bandwidth-regulated fluorescence applications.
独特的上转换或下转换镧系纳米晶体有望应用于生物医学和光子学领域。然而，这两种过程都需要高能激光在离散波长下激发。在这里，我们证明了共敏化可以通过超宽激发带打破这一限制。我们通过采用 Nd 和 Ho 作为共敏化剂，并利用其从紫外到红外区域的互补吸收来实现共敏化。对称的五壳层核壳纳米结构在掺入不同的激活剂（Er、Ho、Pr 和 Tm）时，能够在可见光和第二近红外窗口中实现可调谐荧光。瞬态光谱证实了通过 Yb 的桥梁从敏化剂到激活剂的定向能量转移。我们通过信噪比为 12.3 的低功率白光发光二极管介导的小鼠全身血管造影和激发调节加密来验证纳米晶体的特性。这种共敏化策略为镧系纳米晶体的多方向光子转换操纵和激发带宽调节荧光应用开辟了新途径。
