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Abstract Stability issues in membrane-free coacervates have been addressed with coating strategies, but these approaches often compromise the permeability of the coacervate. Here we report a facile approach to maintain both stability and permeability using tannic acid and then demonstrate the value of this approach in enzyme-triggered drug release. First, we develop size-tunable coacervates via self-assembly of heparin glycosaminoglycan with tyrosine and arginine-based peptides. A thrombin-recognition site within the peptide building block results in heparin release upon thrombin proteolysis. Notably, polyphenols are integrated within the nano-coacervates to improve stability in biofluids. Phenolic crosslinking at the liquid-liquid interface enables nano-coacervates to maintain exceptional structural integrity across various environments. We discover a pivotal polyphenol threshold for preserving enzymatic activity alongside enhanced stability. The disassembly rate of the nano-coacervates increases as a function of thrombin activity, thus preventing a coagulation cascade. This polyphenol-based approach not only improves stability but also opens the way for applications in biomedicine, protease sensing, and bio-responsive drug delivery.
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Carbodiimide‐Fueled Assembly of π‐Conjugated Peptides Regulated by Electrostatic Interactions**
Abstract Peptides naturally have stimuli‐adaptive structural conformations that are advantageous for endowing synthetic materials with dynamic functionalities. Here, we report a carbodiimide‐based approach, combined with electrostatic modulation, to instruct π‐conjugated peptides to self‐assemble and be responsive to thermal disassembly cues upon consumption of the assembly trigger. Quaterthiophene‐functionalized peptides are utilized as a model system herein to study the formation of nanostructures at non‐equilibrium states. Peptides were designed to have aspartic acid at the termini to allow intramolecular anhydride formation upon adding carbodiimide, which consequentially reduces the electrostatic repulsion and facilitates assembly. We show that the carbodiimide‐fueled assembly and subsequent thermally assisted disassembly can be modulated by the net charge of the peptidic monomers, suggesting an assembly mechanism that can be encoded by sequence design. This carbodiimide‐based approach for the assembly of designer π‐conjugated systems offers a unique opportunity to develop bioelectronic supramolecular materials with controllable formation of dynamic and stimuli‐responsive structures.
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- PAR ID:
- 10424075
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSystemsChem
- Volume:
- 5
- Issue:
- 4
- ISSN:
- 2570-4206
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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