posted on 2024-01-05, 20:52authored byGan Zhang, Tingting Liu, Huadong Cai, Yan Hu, Zhifang Zhang, Meifeng Huang, Juan Peng, Weihua Lai
The application of traditional lateral flow immunoassay
(LFIA)-based
gold nanoparticles (AuNPs) to measure traces of target chemicals is
usually challenging. In this study, we developed an integrated strategy
based on molecular engineering and the spatial confinement of nanoparticles
(NPs) to obtain ultrahigh quantum yields (QYs) of aggregation-induced
emission (AIE) fluorescence NPs and employed them for the highly sensitive
detection of T-2 toxin on the LFIA platform. Tetraethyl-4,4′,4″,4‴-(ethene-1,1,2,2-tetrayl)tetrabenzoate
(TCPEME), an AIE luminogen, was designed using molecular engineering
to lower the energy gap, achieving higher QYs (26.26%) than previous
AIEgens (13.02%). Subsequently, TCPEME-doped fluorescence NPs (TFNPs)
achieved ultrahigh QYs, up to 84.55%, which were generated from the
strong restriction of the NP state, efficiently suppressing nonradiative
relaxation channels verified by ultrafast electron dynamics. On the
LFIA platform, the sensitivity of the designed TFNP-based LFIA (TFNP–LFIA)
was 10.4-fold and 4.3-fold more sensitive than that of the AuNP–LFIA
and TPENP–LFIA for detecting the T-2 toxin, respectively. In
addition, TFNP–LFIA was used for detecting T-2 toxin in samples
and showed satisfactory recoveries (79.5 to 122.0%) with CV (1.49
to 11.75%), which implied excellent application potential for TFNP–LFIA.
Overall, dual improvement of the molecule in fluorescence performance
originating from the molecular engineering and spatial confinement
of NPs could be an efficient tool for promoting the development of
high-performance reporters in LFIA.