Scalable and Uniform Length-Tunable Biodegradable Block Copolymer Nanofibers with a Polycarbonate Core via Living Polymerization-Induced Crystallization-Driven Self-assembly

Abstract

Uniform 1D block copolymer (BCP) nanofibers prepared by the seeded-growth approach termed living crystallization-driven self-assembly (CDSA) offer promising potential for various applications due to their anisotropy, length tunability, and variable core and coronal chemistries. However, this procedure consists of a multi-step process involving independent BCP synthesis and self-assembly steps, where the latter is performed at low solution concentrations (<1 wt %), hindering scale-up. Here, we demonstrate the use of a one-pot BCP synthesis and self-assembly process, polymerization-induced CDSA (PI-CDSA), to access length-disperse nanofibers with a biodegradable crystalline poly(fluorenetrimethylenecarbonate) (PFTMC) core and a hydrophilic poly(ethylene glycol) (PEG) corona derived from PEG-b-PFTMC at concentrations up to 20 wt %, 400 times higher than those previously reported. Furthermore, living PI-CDSA could be used to access scalable, low dispersity, and length-tunable 1D PEG-b-PFTMC nanofibers at concentrations of up to 10 wt %. This provides the first example of living PI-CDSA involving an all-organic and biodegradable BCP that utilizes a conveniently implemented BCP synthesis protocol and does not involve living anionic polymerization. Significantly, samples of low-dispersity nanofibers of controlled lengths from 100 to 660 nm (L w/L n = 1.08–1.20) were prepared, allowing for upscaled access to well-defined biodegradable nanofibers at useful length-scales for applications in nanomedicine. Interestingly, detailed studies revealed a key role for PFTMC homopolymer impurities in the BCP prepared in situ in the formation of nanofibers under the reaction conditions used.

Optimization of precision nanofiber micelleplexes for DNA delivery

“…[17][18][19][20][21] Living CDSA has been used to generate precision 1D and 2D nanoparticles for potential use in a range of applications such as optoelectronics, catalysis, surface functionalization, and nanomedicine. [20][21][22][23][24] For applications in the biomedical field a number of polymeric systems capable of undergoing living CDSA to yield 1D nanofibers and 2D platelets have been identified, including π-conjugated polymers [25][26][27] polyesters, [28][29][30][31][32] polycarbonates, [33][34][35][36] and poly(2-oxazoline)s. 37,38 Recent studies have focused on loading drugs 36,39,40 and DNA 25,41,42 for delivery applications, as well as examining antimicrobial activity. [43][44][45] Recently, our group reported the first example of lengthcontrolled nanofiber micelleplexes produced via living CDSA.…”

Self-assembly induced ferromagnetic interaction in magnetic polymers with terphenyl linkers

“…5 Molecular wires are prepared by the crystallization induced self-assembly of semi-crystalline block copolymers. 6–8 Photonic crystals with lamellar structures are prepared by the self-assembly of block copolymers, of which the reflected wavelength is tuned flexibly. 9,10…”

“…5 Molecular wires are prepared by the crystallization induced self-assembly of semi-crystalline block copolymers. [6][7][8] Photonic crystals with lamellar structures are prepared by the self-assembly of block copolymers, of which the reflected wavelength is tuned flexibly. 9,10 The most challenging aspect of block copolymer self-assembly is manipulating the macromolecules or polymer chain into a designed position due to the dynamic self-assembly process.…”

Synthesis of Narrowly Distributed α,ω-Bifunctionalized Conjugated Polymers

“…While great efforts have been devoted to modulating the main chain structure of conjugated polymers, like introducing various kinds of donor–acceptor (D–A) moieties, mitigating backbone defects, and controlling the head-to-tail patterns, ,,, to name a few, one-pot or postpolymerization modification of side chains and end groups also provide great possibilities to significantly enrich the structure and property of conjugated polymers. − Further derivatization at chain ends enables the synthesis of block copolymers for crystallization-driven self-assembly, − decorating nanoparticles for the fabrication of and layered hybrid nanocomposites. Hawker et al introduced perylene diimide (PDI) units at the chain ends of a donor–acceptor-type conjugated polymer PDPP2FT through a one-step strategy and found efficient charge transfer between PDI end groups and PDPP2FT main chains to reveal unique photophysical properties.…”