posted on 2021-05-25, 15:07authored byDan Song, Mengting Zhu, Siyu Chi, Lan Xia, Zhen Li, Zhihong Liu
Real-time
and in situ visualization of cerebrovascular dysfunction
is significant for studying brain injury, which however, is restricted
by the complex brain structure and limited imaging strategies. Luminescence
imaging in NIR-IIb region (1500–1700 nm) is a promising tool
owing to its merits including deep penetration, high resolution, and
fast data acquisition. Unfortunately, a luminescent material in this
region with sufficient brightness and biocompatibility is scarce.
Herein, Ag2Se quantum dot-sensitized lanthanide-doped nanocrystals
(QDs-LnNCs) with emission beyond 1500 nm were fabricated to image
the cerebrovascular structure and hemodynamics in ischemic stroke
and traumatic brain injury. The sensitization by QDs provided an over
100-fold enhanced brightness of LnNCs and a remarkable penetration
depth of 11 mm. Dynamic information of blood perfusion and flow rates
were acquired and the damage of the blood–brain barrier in
the two injury models was investigated. Our results proved QDs-LnNCs
as a kind of competent nanomaterial for noninvasive brain imaging.