Significant advances in the synthesis of polypeptides by N-carboxyanhydride (NCA) polymerisation over last decade have enabled design advanced polypeptide architectures such as star-shaped polypeptides. These materials combine functionality offered amino acids with flexibility creating stable nanoparticles adjustable cargo space for therapeutic delivery. This review highlights recent star NCA followed a critical applications this class polymer delivery agents. includes examples traditional...

We present a star copolypeptide-based hydrogel ink capable of structural microfabrication using 3D extrusion printing. The material comprises an amphiphilic block copolymer structure poly(benzyl-l-glutamate)- b-oligo(l-valine), which spontaneously forms hydrogels through hydrophobic interactions. chemical design allows the bulk phase to remain intact after application shear due its self-recovery behavior. It is demonstrated that composition materials ideally suited for printing with...

The field of tissue engineering is increasingly recognizing that gene therapy can be employed for modulating in vivo cellular response thereby guiding regeneration. However, the lacks a versatile and biocompatible delivery platform capable efficiently delivering transgenes to mesenchymal stem cells (MSCs), cell type often refractory transfection. Herein, we describe extensive systematic exploration three architectural variations star-shaped poly(l-lysine) polypeptide (star-PLL) with varying...

Printing of novel linear polypeptide hydrogel bioinks and stabilisation structures by post-printing UV-triggered crosslinking through catalyst free thiol–yne click chemistry cysteine propiolated 4-arm PEG.

Gene activated scaffolds incorporating star-shaped polypeptide-pDNA nanomedicines accelerate bone tissue regeneration<italic>in vivo</italic>.

Hydrogels hold much promise for 3D printing of functional living materials; however, challenges remain in tailoring mechanical robustness as well biological performance. In addressing this challenge, the modular synthesis hydrogels from 3-arm diblock copolypeptide stars composed an inner poly(l-glutamate) domain and outer poly(l-tyrosine) or poly(l-valine) blocks is described. Physical crosslinking due to ß-sheet assembly these star block copolymers gives stability during extrusion selective...

Abstract A simple method is presented for preparing polypeptide nanoparticles using hydrophilic biosynthetic ε‐poly(lysine) (εPL) as a reactive surfactant under dispersion polymerization conditions. In situ graft of benzyl‐L‐glutamic acid N ‐carboxyanhydride (BLG‐NCA) triggers the self‐assembly amphiphilic copolymers into nanoparticles, which are colloidally stabilized by remaining εPL amino groups at particle surface. The average nanoparticle diameter can be controlled in range 40–120 nm...

Star-shaped amphiphilic block copolymers form hydrogels as opposed to their linear counterparts.

Abstract Hydrogels possess desirable properties for the additive manufacturing of 3D objects, but a significant challenge is to expand range hydrogel feedstocks with defined molecular structure and functionality while retaining mechanical properties. To this end, design photopolymerizable copolypeptides, derived from linear or star‐shaped architectures which can be tailored provide control over associated printing performance, are reported. Based on hydroxy ethyl‐L‐glutamine...

Shear-recoverable hydrogels based on block copolypeptides with rapid self-recovery hold potential in extrudable and injectable 3D-printing applications. In this work, a series of 3-arm star-shaped composed an inner hydrophilic poly(l-glutamate) domain outer β-sheet forming is synthesized varying side chains lengths. By changing the domains, diverse microstructures mechanical properties are prepared structure-function relationships determined using scattering rheological techniques....

Biomolecular assembly processes involving competition between specific intermolecular interactions and thermodynamic phase instability have been implicated in a number of pathological states technological applications biomaterials. As model for such processes, aqueous mixtures oppositely charged homochiral polypeptides as poly-l-lysine poly-l-glutamic acid reported to form either β-sheet-rich solid-like precipitates or liquid-like coacervate droplets depending on competing hydrogen bonding...

Peptide hydrogels have proven to be a critical building block for range of scientific applications due their high water capacity, tunable mechanical properties, and modular synthetic design. Particular interest stems from the biomedical realm inherent biomimetic structure biocompatibility, which has prompted use as 3D printable matrices. In this review, we will discuss two main strategies preparing peptide using solid-phase synthesis (SPPS) N-carboxyanhydride ring opening polymerization (NCA...

Controlling molecular weight, crosslink density and chirality in covalent polypeptide hydrogels allows the independent tuning of rheological, water uptake, degradation antimicrobial properties.

Block sequence controlled triblock copolypeptides comprising a lysine or glutamic acid central block flanked by cysteine and tyrosine blocks combine exceptional hydrogel printability with antimicrobial properties.

Heart failure has a five-year mortality rate approaching 50%. Inducing angiogenesis following myocardial infarction is hypothesized to reduce cardiomyocyte death and tissue damage, thereby preventing heart failure. Herein, novel nano-in-gel delivery system for vascular endothelial growth factor (VEGF), composed of star-shaped polyglutamic acid-VEGF nanoparticles in tyramine-modified hyaluronic acid hydrogel (nano-VEGF-HA-TA), investigated. The ability the nano-VEGF-HA-TA induce assessed vivo...

Strong redox responsive hydrogels with mechanical properties depending on the positioning of oligo(cysteine) within star polypeptides were obtained.

Stromal-Derived Factor 1α (SDF) is an angiogenic, chemotactic protein with significant potential for applications in a range of clinical areas, including wound healing, myocardial infarction and orthopaedic regenerative approaches. The 26-min vivo half-life SDF, however, has limited its translation to date. In this study, we investigate the use star-shaped or linear poly(glutamic acid) (PGA) polypeptides produce PGA–SDF nanoparticles, which can be incorporated into tyramine-modified...

Abstract The first report of star poly(L‐proline) crosslinkers is disclosed for digital light processing 3D printing thermoresponsive hydrogels. Through chain end functionalization poly(L‐proline)s with methacryloyl groups, access to high‐resolution defined hydrogel structures via achieved through photoinitiated free radical polymerization. Changing the molecular weight has a direct influence on both thermoresponsiveness and printability, while shape‐morphing behavior can be induced thermally.

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ABSTRACT This work reports the synthesis of a new difunctional N ‐carboxyanhydride (NCA) monomer, namely diaminopimelic acid (DAP), and its use in one‐pot preparation an organogelating copolypeptide. The organogel is formed situ through ring‐opening polymerization (ROP) DAP NCA from helical poly(ε‐carbobenzyloxy‐L‐lysine) (PZLL) blocks mixture dimethylformamide/chloroform. Gelation occurs by immobilizing solvent core crosslinking stabilized physical intermolecular conformations. After...

A novel 4,4-difuoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) copolymer with diethynylbenzene has been synthesised, and its ability to act as a photosensitiser for the photocatalytic generation of hydrogen was investigated by time-resolved spectroscopic techniques spanning ps- ns-timescales. Both transient absorption infrared spectroscopy were used probe excited state dynamics this photosensitising unit in variety solvents. These studies indicated how environmental factors can influence...