Biocompatible amphiphilic block copolymers comprised of poly(ethylene glycol) (PEG) as the hydrophilic component and a poly(methylcarboxytrimethylene carbonate) (PMTC) as a hydrophobic backbone having either poly(L-lactide) (L-PLA) or poly(D-lactide) (D-PLA) branches were prepared by organocatalytic ring-opening polymerization (ROP). The polycarbonate backbone was prepared by copolymerization of two different MTC-type monomers (MTCs) including a tetrahydropyranyloxy protected hydroxyl group, a masked initiator for a subsequent ROP step. Interestingly, the organic catalyst used in the ROP of MTCs was also effective for acetylation of the hydroxyl end-groups by the addition of acetic anhydride added after polymerization. Acidic deprotection of the tetrahydropyranyloxy (THP) protecting group on the carbonate chain generated hydroxyl functional groups that served as initiators for the ROP of either D- or L-lactide. Comb-shaped block copolymers of predictable molecular weights and narrow polydispersities (approximately 1.3) were prepared with up to 8-PLA branches. Mixtures of the D- and L-lactide based copolymers were studied to understand the effect of noncovalent interactions or stereocomplexation on the properties.
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Talanta
January 2025
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences & Chongqing School, University of Chinese Academy of Science, Chongqing, 400714, PR China. Electronic address:
Polymers and dendrimers are macromolecules, possessing unique and intriguing characteristics, that are widely applied in self-assembled functional materials, green catalysis, drug delivery and sensing devices. Traditional approaches for the structural characterization of polymers and dendrimers involve DLS, GPC, NMR, IR and TG, which provide their physiochemical features and ensemble information, whereas their unimolecular conformation and dispersion also are key features allowing to understand their transporting profile in confined ionic nanochannels. This work demonstrates the nanopore approach for the determination of charged homopolymers, neutral block copolymer and dendrimers under distinct bias potentials and pH conditions.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
State Key Lab of Polymer Materials Engineering, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
Along with the quick advancements in enzyme technology, inactivation has emerged as the key barrier for enzymes to be fully utilized as biocatalysts. Here, a novel strategy is presented for the preservation of the enzymatic activity even after heat treatment by grafting enzymes onto the thermal responsive block copolymer via an activated ester-amine reaction. A new water-soluble activated ester monomer, acrylic polyethylene glycol (PEG) functionalized 3-fluoro-4-hydroxybenzoate is synthesized.
View Article and Find Full Text PDFSoft Matter
January 2025
Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, NO-0315 Oslo, Norway.
Due to the escalating threat of the pathogens' capability of quick adaptation to antibiotics, finding new alternatives is crucial. Although antimicrobial peptides (AMPs) are highly potent and effective, their therapeutic use is limited' as they are prone to enzymatic degradation, are cytotoxic and have low retention. To overcome these challenges, we investigate the complexation of the cationic AMP colistin with diblock copolymers poly(ethylene oxide)--poly(methacrylic acid) (PEO--PMAA) forming colistin-complex coacervate core micelles (colistin-C3Ms).
View Article and Find Full Text PDFInt J Pharm
January 2025
Soft Matter Chemistry, Department of Chemistry, and Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, PB55 00014 Helsinki, Finland. Electronic address:
Drug loaded microfiber scaffolds have potential for sublingual drug delivery due to their fast dissolution time and tunable porosity. Such microfiber scaffolds can be prepared by melt electrowriting (MEW), wherein a polymer melt is electrostatically drawn out of a syringe onto a computer controlled moving collector. The fabrication of such scaffolds via MEW has previously been shown for a polymer with a glass transition temperature (T) just above room temperature, making handling challenging.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Fudan University, Macromolecular Science, No.220, Handan Road, Yangpu District, 200433, Shanghai, CHINA.
Hydrogen sulfide (H2S), as a gasotransmitter, not only plays a vital role in mediating many cellular activities but also manifests exciting applications in clinical therapy. However, one main obstacle in using H2S as a gaseous therapeutic agent is to realize on-demand storage and delivery of gas, and thus, it is of great importance to develop H2S-donating vehicle platforms. Although a variety of polymer-based gas-releasing carriers have been designed, almost all the systems are limited to spherical structures.
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