Sweet Gels That Glow in Many Liquids

Scientists have engineered a new family of low‑molecular‑weight sugar molecules capable of forming glowing gels in a wide array of solvents. By attaching light‑producing groups to the sugar core, they created three distinct variants:

• Naphthalene‑tagged
• Benzothiadiazole‑functionalized
• Coumarin‑ring bearing

All three were synthesized via an environmentally friendly, scalable process.

Versatile Gelation Across Solvent Classes

The gels were tested in:

• Water
• A spectrum of organic solvents with varying polarity
• Deep eutectic solvents (DES)—liquid mixtures that possess unique chemical properties

The coumarin‑based molecule, MCumS, stood out:

• Gels in water, short alcohols, and even hydrophobic DES derived from terpenes
• Demonstrates self‑assembly under markedly different chemical conditions—a challenge for conventional gelators

Structural Insights

• Water: MCumS gels form a fine, fibrous network.
• DES: The microstructure shifts noticeably depending on the specific solvent used.
• Gels with a zwitterionic DES exhibit enhanced mechanical strength and can be extruded through a syringe, hinting at practical applications.

Implications

This research expands the repertoire of fluorescent gelators and deepens our understanding of how subtle molecular tweaks influence gel behavior across diverse environments.