Comparative Investigation of the Chemiluminescent Properties of a Dibrominated Coelenterazine Analog

Abstract

Chemi- and bioluminescence are remarkable light-emitting phenomena, in which thermal energy is converted into excitation energy due to a (bio)chemical reaction. Among a wide variety of chemi-/bioluminescent systems, one of the most well-known and studied systems is that of marine imidazopyrazinones, such as Coelenterazine and Cypridina luciferin. Due to the increasing usefulness of their chemi-/bioluminescent reactions in terms of imaging and sensing applications, among others, significant effort has been made over the years by researchers to develop new derivatives with enhanced properties. Herein, we report the synthesis and chemiluminescent characterization of a novel dibrominated Coelenterazine analog. This novel compound consistently showed superior luminescence, in terms of total light output and emission lifetime, to natural imidazopyrazinones and commercially available analogs in aprotic media, while being capable of yellow light emission. Finally, this new compound showed enhanced chemiluminescence in an aqueous solution when triggered by superoxide anion, showing potential to be used as a basis for optimized probes for reactive oxygen species. In conclusion, bromination of the imidazopyrazinone scaffold appears to be a suitable strategy for obtaining Coelenterazines with enhanced properties.

In vivo three-dimensional brain imaging with chemiluminescence probes in Alzheimer’s disease models

“…The IPO moiety in ADLumin-Xs is the core structural component of cypridina luciferin ( 42 – 44 ). Reportedly, the rate of autooxidation of cypridina luciferin analogues, such as CLA, varies with pH of the solutions ( 45 – 48 ). To investigate the property changes of ADLumin-5 under different pH conditions, we conducted pH titration in buffers.…”

Organic persistent luminescence imaging for biomedical applications

“…Following its oxidation in the presence of luciferase enzyme, Cypridina luciferin emits a blue CL light, and can be achieved at neutral pH. Thus, Cypridina luciferin analogs with imidazopyrazinone structures have been developed as novel and specialized detection systems for the presence of superoxide (O 2 ·- ) in biological applications [ 48 ]. Tang et al.…”

Investigation of the Superoxide Anion-Triggered Chemiluminescence of Coelenterazine Analogs

“…As a result, researchers have been using them as sensitive and dynamic probes for the detection of superoxide anion [13][14][15][27][28][29][30]. In recent years, our group has focused on developing novel Coelenterazine Analogs (CLA) with both new and enhanced properties [32][33][34][35][36][37]. Among the newly obtained compounds, we discovered that certain mono-and dibrominated CLA species exhibited significantly enhanced superoxide anion-triggered chemiluminescent emission in solution compared to native Coelenterazine and commercial analogs [35][36][37].…”