Peptide Coacervates as Dynamic and Interactive Depots for Tetrodotoxin in Long-Acting Local Anesthesia
Xing Wang1, Jiahao Zhang1, Wen Liu1
1Department of Chemistry, Georgia State University, Atlanta, Georgia, USA.
Advanced Healthcare Materials
|August 4, 2026
Summary
Researchers developed a novel peptide coacervate system for sustained release of hydrophilic drugs. This platform effectively encapsulates tetrodotoxin (TTX), extending local anesthesia duration and reducing systemic toxicity in preclinical models.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Nanotechnology
Background:
- Hydrophilic small-molecule therapeutics face challenges in conventional depot delivery due to high water solubility and rapid diffusion.
- Developing effective delivery systems for potent hydrophilic drugs like tetrodotoxin (TTX) is crucial for advanced therapeutic applications.
Purpose of the Study:
- To establish a novel drug-interactive peptide coacervate platform for sustained release of hydrophilic therapeutics.
- To investigate the encapsulation and release characteristics of tetrodotoxin (TTX) using a mussel foot protein-inspired peptide (Mfp3s-pep).
Main Methods:
- Utilized a mussel foot protein-inspired peptide (Mfp3s-pep) for spontaneous self-coacervation under physiological conditions.
- Encapsulated tetrodotoxin (TTX) within the peptide coacervate assemblies through multivalent noncovalent interactions.
- Evaluated the sustained release of TTX and its efficacy in a rat sciatic nerve block model, complemented by molecular docking and dynamics simulations.
Main Results:
- The Mfp3s-pep coacervates successfully encapsulated 29% of TTX, significantly prolonging its release profile.
- The TTX-Mfp3s-pep formulation extended sensory blockade duration up to 10.5 hours in a rat model.
- Systemic toxicity was reduced by 1.5-fold compared to TTX alone, demonstrating improved safety and efficacy.
Conclusions:
- Peptide coacervates offer a promising platform for the sustained delivery of challenging hydrophilic therapeutics.
- The Mfp3s-pep coacervate system demonstrates potential for enhancing the therapeutic index of drugs like TTX.
- This approach advances the development of novel drug delivery strategies for local anesthesia and potentially other hydrophilic drugs.
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