Fundamental synthetic methodology was advanced to allow for the preparation of a reactive glucose-based block copolycarbonate, which was conveniently transformed into a series of amphiphilic block copolymers that underwent aqueous assembly into functional nanoparticle morphologies having practical utility in biomedical and other applications. Two degradable d -glucose carbonate monomers, with one carrying alkyne functionality, were designed and synthesized to access well-defined block polycarbonates ( Đ < 1.1) via sequential organocatalytic ring opening polymerizations (ROPs). Kinetic studies of the organocatalyzed sequential ROPs showed a linear relationship between the monomer conversion and the polymer molecular weight, which indicated the controlled fashion during each polymerization. The pendant alkyne groups underwent two classic click reactions, copper-catalyzed azide–alkyne dipolar cycloaddition (CuAAC) and thiol–yne addition reactions, which were employed to render hydrophilicity for the alkyne-containing block and to provide a variety of amphiphilic diblock poly( d -glucose carbonate)s (PGCs). The resulting amphiphilic PGCs were further assembled into a family of nanostructures with different sizes, morphologies, surface charges and functionalities. These non-ionic and anionic nanoparticles showed low cytotoxicity in RAW 264.7 mouse macrophage cells and MC3T3 healthy mouse osteoblast precursor cells, while the cationic nanoparticles exhibited significantly higher IC 50 (162 μg mL −1 in RAW 264.7; 199 μg mL −1 in MC3T3) compared to the commercially available cationic lipid-based formulation, Lipofectamine (IC 50 = 31 μg mL −1 ), making these nanomaterials of interest for biomedical applications.
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Controlled Synthesis and Properties of Poly( l -homoserine)
We report preparation of a new water soluble, non-ionic homopolypeptide poly(L-homoserine) as well as poly(L-homoserine) block copolymers with controllable segment lengths. The conformational preferences of poly(L-homoserine) were also determined in both the solid-state and in solution. Poly(L-homoserine) is soluble in water and adopts a disordered conformation that makes it a promising addition to the small class of non-ionic, water soluble homopolypeptides with potential for development for applications in biology. Toward this goal, a poly(L-homoserine) containing block copolypeptide was prepared and found to assemble into micro- and nanoscale vesicles in water.
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- Award ID(s):
- 1904431
- NSF-PAR ID:
- 10488931
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Macro Letters
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2161-1653
- Page Range / eLocation ID:
- 518 to 522
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsmacrolett.3c00122
