Design,Synthesis And Properties Of Indanone Enhanced Fluorescent Probes For The Detection Of Cysteine

Cysteine(Cys)is a multifunctional amino acid containing sulfhydryl in the body,which plays an important role in the process of life.The analysis and detection of cysteine has been a research hotspot in recent years.Fluorescence spectrometry has been widely concerned for its advantages of simple detection,short response time,good selectivity,high sensitivity,fast reaction speed and low cost.In this paper,hydroxyl-containing indanone is used as a fluorophore,starting from molecular structure innovation,using the influence of modified groups on the optical properties of the primary fluorophore,two novel indanone-based enhanced fluorescent molecular probes IND-Cys1 and WF-Cys are designed and synthesized.Different from the"regulation"process on the conventional linearly arranged donor-?-acceptor system,we use the influence of the modified group on the optical properties of the primary fluorophore,and by introducing different arylene units,the structure modification of the indanone affects the electron withdrawing potential of the C=O unit on the indanone.Based on the ICT fluorescence reaction mechanism,we chose the classic acryloyl group as the fluorescence recognition group,based on the Michael addition reaction,to achieve the rapid and specific reaction of cysteine.The probes IND-Cys1 and WF-Cys were prepared by Knoevenagel reaction,and both were characterized by structural analysis methods such as proton nuclear magnetic resonance(¹H NMR)and carbon spectroscopy(¹³C NMR)mass spectrometry(HR-MS).Using ultraviolet absorption spectrometer,fluorescence spectrometer,etc.to explore the spectroscopic properties of IND-Cys1 and WF-Cys probes,the recognition mechanism of cysteine and the selectivity to cysteine,the cellular level of cysteine Study on acid fluorescence imaging.The results showed that the IND-Cys1 and WF-Cys probes both showed obvious fluorescence response signals,large Stoke shifts(175 nm and 136 nm,respectively),fast response time(saturation in 20 min)and Low detection limits(0.08?M,0.14?M,respectively).Therefore,the“OFF-ON”fluorescence detection of cysteine can be realized.