title: Styryl-BODIPY based red-emitting fluorescent OFF-ON molecular probe for specific detection of cysteine.
abstract: We have synthesized a styryl boron-dipyrromethene (BODIPY)/2,4-dinitrobenzenesulfonyl (DNBS) dyad based red-emitting molecular probe for specific detection of cysteine among the biological thiols. The probe shows intensive absorption at 556 nm and the probe is non-fluorescent. The DNBS moiety can be cleaved off by thiols, the red emission of the BODIPY fluorophore at 590 nm is switched on, with an emission enhancement of 46-fold. The probe shows good specificity toward cysteine over other biological molecules, such as glutathione and amino acids. The emission of the probe is pH-independent in the physiological pH range. The probe is used for fluorescent imaging of cellular thiols. Theoretical calculations based on density functional theory (DFT) were used to elucidate the fluorescence sensing mechanism of the probe, which indicate a dark excited state (S(1)) for the probe but an emissive excited state (S(1)) for the cleaved product (i.e. the fluorophore).
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemical Engineering, 158 Zhongshan Road, Dalian University of Technology, Dalian 116012, PR China.
authors.forename: Jingyin
authors.initials: J
authors.lastname: Shao
authors.forename: Huimin
authors.initials: H
authors.lastname: Guo
authors.forename: Shaomin
authors.initials: S
authors.lastname: Ji
authors.forename: Jianzhang
authors.initials: J
authors.lastname: Zhao
mesh_terms: D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D001896:Boron Compounds / Q000138:chemical synthesis / Q000737:chemistry; D003545:Cysteine / Q000032:analysis*; D004139:Dinitrofluorobenzene / Q000031:analogs & derivatives / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D015336:Molecular Probe Techniques; D015335:Molecular Probes / Q000138:chemical synthesis / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013343:Styrenes / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D005456:Fluorescent Dyes; D015335:Molecular Probes; D013343:Styrenes; D013438:Sulfhydryl Compounds; C045305:2,4-dinitrofluorobenzene sulfonic acid; D004139:Dinitrofluorobenzene; D003545:Cysteine