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Polymeric nanoparticles containing multiple amines and carboxylates have been frequently used in drug delivery research. Reproducible and controlled conjugation among these multifunctional biomaterials is necessary to achieve efficient drug delivery platforms. However, multiple functional groups increase the risk of unintended intramolecular/intermolecular reactions during conjugation. Herein, conjugation approaches and possible undesired reactions between multi-amine functionalized peptides, multi-carboxylate functionalized polymers, and anhydride-containing polymers [Poly(styrene-alt-maleic anhydride)-b-poly(styrene)] were investigated under different conjugation strategies (carbodiimide chemistry, anhydride ring-opening via nucleophilic addition elimination). Muti-amine peptides led to extensive crosslinking between polymers regardless of the conjugation chemistry. Results also indicate that conventional peptide quantification methods (i.e., o-phthalaldehyde assay, bicinchoninic acid assay) are unreliable. Gel permeation chromatography (GPC) provided more accurate qualitative and quantitative evidence for intermolecular crosslinking. Crosslinking densities were correlated with higher feed ratios of multifunctional peptides and carbodiimide coupling reagents. Selectively protected peptides (Lys-Alloc) exhibited no crosslinking and yielded peptide-polymer conjugates with controlled dispersity and molecular weight. Furthermore, anhydride ring-opening (ARO) nucleophilic addition elimination was successfully introduced as a facile yet robust peptide conjugation approach for cyclic anhydride-containing polymers.
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Facile Synthesis of Multifunctional Bioreducible Polymers for mRNA Delivery
Abstract Bioreducible polymeric mRNA carriers are an emerging family of vectors for gene delivery and vaccine development. A few bioreducible systems have been generated through aqueous‐phase ring‐opening polymerization of lipoic acid derivatives, however this methodology limits hydrophobic group incorporation and functionality into resulting polymers. Herein, a poly(active ester)disulfide polymer is synthesized that can undergo facile aminolysis with amine‐containing substrates under stoichiometric control and mild reaction conditions to yield a library of multifunctional polydisulfide polymers. Functionalized polydisulfide polymer species form stable mRNA‐polymer nanoparticles for intracellular delivery of mRNAsin vitro. Alkyl‐functionalized polydisulfide‐RNA nanoparticles demonstrate rapid cellular uptake and excellent biodegradability when delivering EGFP and OVA mRNAs to cellsin vitro. This streamlined polydisulfide synthesis provides a new facile methodology for accessing multifunctional bioreducible polymers as biomaterials for RNA delivery and other applications.
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- Award ID(s):
- 2004555
- PAR ID:
- 10398787
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 12
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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