title: Highly sensitive and selective phosphorescent chemosensors for hypochlorous acid based on ruthenium(II) complexes.
abstract: Microbicidal activity of hypochlorous acid (HOCl) plays pivotal roles in many biological processes, and suitable methods for the in vivo detection of HOCl are highly desirable. Herein we report the development of two novel ruthenium(II) complex-based phosphorescent chemosensors for HOCl, [Ru(bpy)2(DNCA-bpy)](PF6)2 (bpy: 2,2'-bipyridine; DNCA-bpy: 4-N-(2,4-dinitrophenyl)carboxamide-4'-methyl-2,2'-bipyridine) and [Ru(bpy)2(DNCH-bpy)](PF6)2 (DNCH-bpy: 4-N'-(2,4-dinitrophenyl)carbohydrazide-4'-methyl-2,2'-bipyridine). The two sensors are almost non-luminescent due to the intramolecular photoinduced electron transfer (PET) process from the Ru(II)-bpy moiety to dinitrophenyl group, but specific reaction of the sensors with HOCl in aqueous media can afford a highly luminescent derivative, [Ru(bpy)2(COOH-bpy)](PF6)2 (COOH-bpy: 4-carboxylic acid-4'-methyl-2,2'-bipyridine), accompanied by 190-fold and 1100-fold turn-on luminescence signal enhancement for [Ru(bpy)2(DNCA-bpy)](PF6)2 and [Ru(bpy)2(DNCH-bpy)](PF6)2, respectively. By taking advantage of high specificity and sensitivity of the chemosensor and excellent photophysical property of Ru(II) complex, [Ru(bpy)2(DNCH-bpy)](PF6)2 was applied for visualizing the endogenous HOCl generation in living macrophage cells during the processes of stimulation and phagocytosis via the red-emitting luminescence.
authors.affiliation: State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, PR China.
authors.forename: Run
authors.initials: R
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.forename: Zhichao
authors.initials: Z
authors.lastname: Dai
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Ye
authors.forename: Yunna
authors.initials: Y
authors.lastname: Xiao
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Jingli
authors.initials: J
authors.lastname: Yuan
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry; D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002460:Cell Line; D006367:HeLa Cells; D006801:Humans; D006997:Hypochlorous Acid / Q000032:analysis* / Q000378:metabolism; D049408:Luminescent Agents / Q000737:chemistry*; D008264:Macrophages / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D051379:Mice; D061848:Optical Imaging / Q000379:methods; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D049408:Luminescent Agents; D015082:2,2'-Dipyridyl; D006997:Hypochlorous Acid; D012428:Ruthenium
keywords: Hypochlorous acid; Luminescence imaging; Phosphorescent chemosensor; Ruthenium(II) complex