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A Facile and Efficient Approach for the Production of Reversible Disulfide Cross-linked Micelles
Published on: December 23, 2016
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Controlling the function of bioactive worm micelles by enzyme-cleavable non-covalent inter-assembly cross-linking
Alina Romanovska1, Martin Schmidt1, Volker Brandt1
1Biomaterials and Polymer Science, Department of Bio- and Chemical Engineering, TU Dortmund, Emil-Figge-Straße 66, 44227 Dortmund, Germany.
Summary
Researchers developed a new method to control drug activity using self-assembled nanostructures. By cross-linking polymer-antibiotic worm micelles, they created nanoparticles with significantly reduced activity, which could be restored by enzyme cleavage, offering precise pharmaceutical control.
Area of Science:
- Supramolecular Chemistry
- Polymer Science
- Pharmaceutical Nanotechnology
Background:
- Self-assembled supramolecular structures offer a promising avenue for developing highly specific and active pharmaceuticals.
- Controlling the activity of bioactive supramolecular structures like drug-loaded micelles is crucial but challenging, especially when assembly flexibility is required for activity.
- Existing methods like cross-linking are often not feasible for flexible assemblies, limiting activity manipulation.
Purpose of the Study:
- To demonstrate a novel concept for controlling the activity of non-drug-releasing, non-cross-linked bioactive superstructures.
- To develop a method for activity modulation using nanostructured nanoparticles formed by non-covalent inter-assembly cross-linking.
- To investigate the reversible activity control of polymer-antibiotic conjugates.
Main Methods:
- Synthesis of amphiphilic diblock copolymers conjugated with ciprofloxacin (CIP) to form worm micelles.
- Non-covalent inter-assembly cross-linking of CIP-worm-micelles with amphiphilic triblock copolymers containing lipase-cleavable esters.
- Evaluation of the antibacterial activity of the resulting nanostructured nanoparticles and free worm micelles.
- Demonstration of reversible activity control via lipase-mediated cleavage of cross-linker end groups.
Main Results:
- Polymer-ciprofloxacin conjugates formed worm micelles that significantly activated the antibiotic without drug release.
- Non-covalent cross-linking of these worm micelles resulted in nanostructured nanoparticles with up to 135-fold lower activity compared to free micelles.
- The reduced activity of the nanostructured nanoparticles was fully reversible upon cleavage of the cross-linker's lipase-cleavable ester groups.
Conclusions:
- A novel strategy for controlling the activity of bioactive supramolecular assemblies through non-covalent inter-assembly cross-linking has been successfully demonstrated.
- This method allows for the precise modulation of pharmaceutical activity in non-drug-releasing nanostructures.
- The reversible nature of the cross-linking offers potential for developing advanced drug delivery systems with tunable therapeutic effects.
Keywords:
CiprofloxacinCross-linked micellesLipase-induced releasePoly(2-oxazoline)Polymer antibtiotic conjugateMore Related Videos
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