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Aims: Stimuli-responsive polymersomes are promising tools for protein-based therapies, but require deeper understanding and optimization of their pathology-responsive behavior. Materials & methods: Hyaluronic acid (HA)–poly(b-lactic acid) (PLA) polymersomes self-assembled from block copolymers of varying molecular weights of HA were compared for their physical properties, degradation and intracellular behavior. Results: Major results showed increasing enzyme-responsivity associated with decreasing molecular weight. The major formulation differences were as follows: the HA(5 kDa)–PLA formulation exhibited the most pronounced release of encapsulated proteins, while the HA(7 kDa)–PLA formulation showed the most different release behavior from neutral. Conclusion: We have discovered design rules for HA–PLA polymersomes for protein delivery, with lower molecular weight leading to higher encapsulation efficiency, greater release and greater intracellular uptake.
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Poly(Piloty's acid): a slow releasing macromolecular HNO donor
We report a polymeric version of Piloty's acid where the release rate of HNO can be tuned by changing the block ratios of PEG- b -poly(Piloty's acid) in a block copolymer system. The poly(Piloty's acid) block was derived from poly(styrene sulfonate), and HNO release from the block copolymers varied by as much as an order of magnitude via increasing the length of the poly(Piloty's acid) block. We anticipate this study will guide the development of HNO-releasing polymers to measure the effects of sustained HNO delivery in biological systems.
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- Award ID(s):
- 2003662
- PAR ID:
- 10420126
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 14
- Issue:
- 21
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 2572 to 2576
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2py01339h
