Design, Synthesis and Photochemical Properties of a Phenalenone-Based pH Sensor: Switchable pH Sensing in Four Detectable Channels

A novel 2-aminophenalenone-based fluorescent probe designed for monitoring H2O2 for in vitro and in vivo bioimaging

A significant compound in living organisms, hydrogen peroxide (H2O2) plays a dual role as a signalling molecule in cellular communication and as a pivotal biomarker in assessing disease and oxidative stress. Thus, the detection of abnormal changes in H2O2 levels is essential to understanding its function and involvement in biological systems. The growing demand to meet the specific needs for applications, particularly in biological systems, has sharpened focus on highly sensitive, highly selective molecular sensors and, in turn, heightened interest in these diagnostic tools with innovative designs. In our study, 2-aminophenalenone (2-AP) was used for the first time as a fluorophore in a fluorescent probe. The 2-APB molecule obtained from the reaction of 2-AP with 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) benzyl chloroformate exhibited a highly selective and sensitive (i.e. 62 nM) detection profile for H2O2 compared with the other reactive oxygen species, anions, and metal cations. Moreover, offering naked-eye detection in aqueous solutions, 2-APB demonstrated excellent sensing performance, detection and real-time monitoring in relation to exogenous H2O2 in cells and endogenous H2O2 in zebrafish embryos.

A Phenalenone-based Fluorescent Probe for the Detection of Fe3+ ions

A phenalenone based "turn on" probe was developed for selective and sensitive detection of Fe³⁺ ions in aqueous solutions. The thiophene-2-carboxaldehyde (receptor unit) was integrated into the 6-amino-1-phenalenone (6-AP) (signal reporter unit) through the C = N bond formation. The probe, 6-APT, operated through subsequent hydrolysis of the C = N bond induced by the coordination of Fe³⁺ ions to the heteroatoms to form highly fluorescent 6-AP. The probe displayed remarkable characteristics such as rapid response time (< 1 min), high analyte selectivity, and low limit of detection (1.3 µM). The sensing approach offered an accurate method for the detection of Fe³⁺ ions in real water samples (tap water and drinking water). In addition to the fluorometric response, the presence of Fe³⁺ ions can be monitored under daylight by the change in the color of the solution. Importantly, this study is the first example of a phenalenone-based sensor developed for metal ion sensing in literature.

Phenalenyl based platinum anticancer compounds with superior efficacy: design, synthesis, characterization, and interaction with nuclear DNA

New and efficacious phenalenyl based Pt(ii) compounds have been used to design an “easy to use tool” for mechanistic understanding.

“Off–on–off” type of selectively pH-sensing 8-hydroxyquinoline-substituted gallium(iii) corrole

We herein reported the synthesis and pH sensing property of a novel gallium corrole derivatives based on 8-hydroxyquinoline. Ga-corrole derivative showed good fluorescent response upon changing the pH values in the wide region of pH 1 to 12.