Cyclodextrin-Based Nanogels with Chemistry-Tunable Intracellular Stability and Distribution

Area of Science:

• Biomaterials Science
• Nanotechnology
• Drug Delivery Systems

Background:

• Cyclodextrin-based nanogels (CD-nGels) are effective for encapsulating hydrophobic drugs in hydrophilic networks.
• Host-guest interactions improve drug solubility, stability, and therapeutic efficacy.

Purpose of the Study:

• To synthesize fluorescent CD-nGels with tunable hydrolytic properties.
• To investigate the impact of chemical composition on intracellular stability and drug distribution.

Main Methods:

• Surfactant-free synthesis of Nile Blue-labeled CD-nGels with varying amide and ester linkages.
• Characterization of nanogel size (247-431 nm) and hydrolytic sensitivity at pH 5.1 and in cell lysate.
• Encapsulation of Coumarin-6 (C6) and visualization of intracellular distribution via confocal microscopy.

Main Results:

• Three CD-nGel formulations (NG1, NG2, NG3) showed tunable hydrolytic sensitivity.
• Intracellular stability was dictated by chemical composition, with ester linkages increasing degradability.
• CD-nGels demonstrated distinct intracellular fluorescence patterns correlating with degradability, from compact to diffuse.

Conclusions:

• A modular platform for chemically tuning CD-nGel intracellular stability and distribution was established.
• This provides a design basis for developing CD-based nanogels for controlled intracellular drug delivery.