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Dual-Stimuli Responsive Cystamine-Modified Polydopamine Coatings as Payload Gatekeepers
Sylwia Ostrowska1, Monika Szukowska1, Yeonho Kim2
1Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego St. 8, 61-614 Poznań, Poland.
Molecules (Basel, Switzerland)
|July 28, 2026
Summary
We developed tunable, redox-responsive polydopamine coatings for mesoporous silica nanoparticles, enabling controlled drug release. Adjusting the cystamine ratio fine-tuned shell properties and drug delivery, offering a novel bioinspired approach.
Area of Science:
- Materials Science
- Nanotechnology
- Biomedical Engineering
Background:
- Mesoporous silica nanoparticles (MSNs) are promising for drug delivery.
- Current functionalization methods for MSNs can be complex.
- Stimuli-responsive coatings are needed for controlled drug release.
Purpose of the Study:
- To create tunable, stimuli-responsive coatings for MSNs using cystamine-modified polydopamine (PDA).
- To investigate the impact of cystamine incorporation on PDA coating properties and drug release kinetics.
- To establish structure-property relationships for designing advanced drug delivery systems.
Main Methods:
- Incorporation of cystamine directly into the PDA network during nanoparticle synthesis.
- Tuning the dopamine-to-cystamine ratio to control shell composition and responsiveness.
- Characterization using SEM, TGA, FTIR, and zeta potential measurements.
- In vitro release studies of doxorubicin (DOX) and sorafenib (SO) under varying pH and redox conditions.
Main Results:
- Achieved pH- and redox-responsive drug release (DOX, SO) following the Higuchi model.
- Demonstrated tunable shell properties and protective capabilities influenced by cystamine content.
- Found that increasing disulfide content did not always enhance release, indicating potential diffusion limitations from excessive crosslinking.
Conclusions:
- Cystamine-modified PDA coatings offer a tunable platform for stimuli-responsive drug delivery from MSNs.
- The dopamine-to-cystamine ratio is a critical factor in controlling coating properties and drug release.
- Disulfide linkages play a significant role in bioinspired, stimuli-responsive nanomaterials for drug delivery.
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