TY - JOUR
T1 - Molecular Crystal Engineering of Organic Chromophores for NIR-II Fluorescence Quantification of Cerebrovascular Function
AU - Li, Yuanyuan
AU - Fan, Xiaoxiao
AU - Li, Yirun
AU - Liu, Shunjie
AU - Chuah, Clarence
AU - Tang, Youhong
AU - Kwok, Ryan T.K.
AU - Lam, Jacky W.Y.
AU - Lu, Xuefeng
AU - Qian, Jun
AU - Tang, Ben Zhong
PY - 2022/2/22
Y1 - 2022/2/22
N2 - Although molecular design strategies for highly bright near-infrared II (NIR-II) fluorophores were proposed, the lack of solid structural identification (single crystal) hinders the further development of this field. This thorny issue is addressed by performing the structure-function relationship of NIR-II dyes, as confirmed by molecular single crystal engineering. Single crystal structure analysis confirms that twisted architectures (large dihedral angles ∼70°) and loose packing patterns (intermolecular distance of ∼3.4-4.5 Å) are key elements to enhance the absolute quantum yield (QY) in the solid state. Through regulating donor-acceptor distance and donor-acceptor interactions, the resultant well-defined TBP-b-DFA fluorophore displays an absolute QY of 0.4% with an emission extending to 1400 nm, which is favorable for NIR-II bioimaging. The cerebrovascular function, including cerebral blood flow and cerebrovascular reactivity of different conditions, is accurately quantified by a NIR-II fluorescence wide-field microscope. Our study provides a sight for designing NIR-II fluorophores, which is useful for studying cerebrovascular function.
AB - Although molecular design strategies for highly bright near-infrared II (NIR-II) fluorophores were proposed, the lack of solid structural identification (single crystal) hinders the further development of this field. This thorny issue is addressed by performing the structure-function relationship of NIR-II dyes, as confirmed by molecular single crystal engineering. Single crystal structure analysis confirms that twisted architectures (large dihedral angles ∼70°) and loose packing patterns (intermolecular distance of ∼3.4-4.5 Å) are key elements to enhance the absolute quantum yield (QY) in the solid state. Through regulating donor-acceptor distance and donor-acceptor interactions, the resultant well-defined TBP-b-DFA fluorophore displays an absolute QY of 0.4% with an emission extending to 1400 nm, which is favorable for NIR-II bioimaging. The cerebrovascular function, including cerebral blood flow and cerebrovascular reactivity of different conditions, is accurately quantified by a NIR-II fluorescence wide-field microscope. Our study provides a sight for designing NIR-II fluorophores, which is useful for studying cerebrovascular function.
KW - aggregation-induced emission
KW - cerebrovascular function
KW - donor−acceptor interactions
KW - molecular crystal engineering
KW - near-infrared II fluorescence imaging
UR - http://www.scopus.com/inward/record.url?scp=85125020541&partnerID=8YFLogxK
U2 - 10.1021/acsnano.1c11424
DO - 10.1021/acsnano.1c11424
M3 - Article
C2 - 35156810
AN - SCOPUS:85125020541
SN - 1936-0851
VL - 16
SP - 3323
EP - 3331
JO - ACS Nano
JF - ACS Nano
IS - 2
ER -