A Universal Gd³⁺-based hydrogel matrix for inducing room-temperature phosphorescence.

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Biophysics

Background:

• Achieving room-temperature phosphorescence (RTP) in aqueous media is challenging due to oxygen and water quenching.
• Excited triplet states are susceptible to quenching, limiting phosphorescent applications in biological environments.

Purpose of the Study:

• To develop a hydrogel matrix capable of inducing and sustaining room-temperature phosphorescence (RTP) in aqueous solutions.
• To create a universal RTP platform for diverse guest molecules with applications in bioimaging and encoding.

Main Methods:

• Assembly of a hydrogel matrix using Gadolinium(III) ions (Gd3+) and adenosine monophosphate (AMP).
• Encapsulation of guest molecules within the Gd3+-AMP hydrogel matrix.
• Characterization of RTP properties, including afterglow duration and efficiency.
• Evaluation of the hydrogel's stimuli-responsive, shear-thinning, and biocompatible properties.

Main Results:

• The Gd3+-AMP hydrogel effectively promoted intersystem crossing (ISC) and provided oxygen shielding, enabling efficient RTP.
• Second-scale afterglow (>1 s) was achieved for thioflavin T (ThT)-encapsulated hydrogels, demonstrating high matrix efficiency.
• The hydrogel matrix demonstrated universal encapsulation capabilities for diverse guest molecules without size or charge limitations.
• Stimuli-responsive, shear-thinning, and biocompatible properties were confirmed for the hydrogel.

Conclusions:

• The Gd3+-AMP hydrogel serves as a versatile platform for inducing RTP in aqueous media, overcoming traditional limitations.
• The developed hydrogel enables efficient RTP emission from various encapsulated molecules, paving the way for advanced applications.
• Applications demonstrated include bioimaging, 3D encoding, and color-tunable white-light emission, highlighting the hydrogel's potential in diverse fields.