“Real-time imaging and sensing of multiple neurotransmitters in neurons based on column” 5 “arene host-object recognition system

2022-04-29 0 By

Neurotransmitters play an important role in maintaining physiological processes, such as regulating metabolism, participating in neuroregulation and influencing organ function.Abnormal concentration of neurotransmitters can lead to a variety of neurological disorders such as depression and anxiety.The highly selective analysis of neurotransmitters is a challenging task because of their highly similar molecular structures.Aptamer screening provides an effective way to identify neurotransmitters, but it is still an unsolved problem to realize rapid imaging and simultaneous detection of multiple neurotransmitters in neurons.East China normal university Tian Yang group proposed the supramolecular subject and many sites recognition sensing model strategy, designed and synthesized a kind of dual functional column [5] arene (CN – DFP5), on the edge of flange and modify the boric acid and coumarin derivatives of fluorescent recognition, on the basis of the establishment of a variety of neurotransmitters detection fluorescent sensors array.Seven neurotransmitters were selected as research models (Figure 1A) and grouped into three categories (catechols, monoamines, and charge neurotransmitters).Cn-dfp5 binds to seven neurotransmitters through three modes of action :(I) the boric groups on the upper edge of cn-dfp5 capture catechol neurotransmitters (DA, NE, Ep) through condensation reaction;(ii) The aldehyde coumarin group at the lower edge interacts with the monoamine neurotransmitters (HA, 5-HT, DA, NE, Glu) through the condensation reaction of aldehyde amine;(iii) The electron-rich cavity of CN-DFP5 binds charged neurotransmitter (Ach) by electrostatic action, as shown in Figure 1.Ls-ms and NMR titration results confirmed the structure of supramolecules and their interactions with neurotransmitters.Figure 1. (a) Molecular structure of seven neurotransmitters;(b) Synthesis strategy of coumarin-naphthalimide derived column [5] arene (CN-DFP5);(c) Interaction patterns between CN-DFP5 and three neurotransmitters.Therefore, the developed CN-DFP5 supramolecular sensor array produced different fluorescence reaction recognition patterns with seven neurotransmitters, and principal component analysis (PCA) was used to process the corresponding fluorescence signals, realizing the high-throughput recognition of seven neurotransmitters.DFT calculations and experimental data of transient absorption spectra confirm that intermolecular interactions produce changes in molecular energy levels, resulting in different electron transport.Cn-dfp5 supramolecular sensor array not only showed high sensitivity to neurotransmitters in biological fluids, but also successfully imaged and biosensed seven neurotransmitters in living neurons and tissues (Figure 2).Figure 2. Recognition of neurotransmitters in living neurons by CN-DFP5 probe.(a) Co-localization of CN-DFP5 and Cell-Tracker Red;(b) Two-photon fluorescence imaging of cn-DFP5 and neurons co-cultured with DA, NE, Ep, HA, 5-HT, Glu and Ach;(c) Histogram of corresponding fluorescence changes at 435 and 535 nm;(d) PCA plots of the response of CN-DFP5 sensor array to seven neurotransmitters in neurons;(e) Three-dimensional single-photon and two-photon fluorescence imaging of the hippocampal region of AD mouse brain labeled with CN-DFP5 probe.This work has led to the design and synthesis of a new supramolecular sensor array that opens new avenues for highly selective identification and real-time imaging of multiple neurotransmitters in vivo, which will help understand brain activity and facilitate non-invasive diagnosis of neuronal disease.The pattern recognition strategy of this study can be extended to the recognition of other active molecules, such as amino acids, proteins, etc., which will provide new research methods and tools for in vivo research.Source: Frontiers of Polymer Science