A Ratiometric Afterglow Response of Aluminium Ions in Methanol‐Water

• Published in: Chemistry, an Asian journal an Asian journal, 2022-08, Vol.17 (16), p.e202200402-n/a
• Main Authors: Koga, Ayumi, Kawaguchi, Kaede, Maida, Margarita Claudya, Kubo, Yuji
• Format: Article
• Language: English
• Subjects: Afterglow; Afterglows; Aluminum; Boronic acid; Chemical sensors; Chemistry; Chemoreceptors; Chemosensor; Dyes; Emission; Energy transfer; Nanoparticles; Phosphorescence; Rhodamine
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.202200402

An afterglow is beneficial as an emission signal in the field of displays and imaging probes. Here, boronic acid‐appended and spirolactam ring‐containing rhodamine dye 1 was synthesized and grafted onto the surface of room‐temperature phosphorescence‐active boronate nanoparticles (BPs), composed of polymeric 3‐benzo‐2,4,8,10‐tetraoxa‐3,9‐diboraspiro[5.5]undecane. The resultant ensemble, 1@BP, exhibited a greenish afterglow. However, the addition of Al3+ into the dispersion solution with 1@BP led to a change in the afterglow to grass green as a result of Förster‐type energy transfer from the phosphorescent BP to the Al3+‐interacting rhodamine dye 1 on the surface. Based on the ratio of the two emission intensities, a linear response in the concentration range of 3.8–15.2 μM was observed, with a detection limit of 4.2 μM for Al3+. A metal ion‐dependent discernable color in afterglow was observed on a 1@BP‐coated filter paper, which would be useful for not only film‐based afterglow chemosensors but also encryption application. A boronic acid‐appended and spirolactam ring‐containing rhodamine dye was synthesized and grafted onto the surface of RTP‐active boronate nanoparticles. The addition of Al3+ into the dispersion solution of the resultant ensemble 1@BP in MeOH/H2O (95 : 5 v/v) led to a change in the afterglow, enabling visually detection of the metal ion after ceasing irradiation light.