Spyridon Varlas

John Wiley And Sons

Covalent PEGylation of biologics has been widely employed to reduce immunogenicity, while improving stability and half-life in vivo. This approach requires covalent protein modification, creating a new entity. An alternative approach is stabilization by encapsulation into polymersomes; however this typically requires multiple steps, and the segrega...

Polymeric vesicles (or polymersomes) are hollow bilayer structures consisting of an inner aqueous compartment enclosed by a hydrophobic membrane. Vesicular constructs are ubiquitous in nature and perform a variety of functions by compartmentalizing molecules into disparate environments. For polymer chemists, the synthesis of vesicles can be readily...

The dynamic interactions of membranes, particularly their fusion and fission, are critical for the transmission of chemical information between cells. Fusion is driven by elastic membrane tension built up through membrane deformation. For artificial polymersomes, fusion is commonly induced via the external application of a force field. Herein, fusi...

Polymerization-induced self-assembly (PISA) has been widely utilized as a powerful methodology for the preparation of various self-assembled AB diblock copolymer nano-objects in aqueous media. Moreover, it is well-documented that chain extension of AB diblock copolymer vesicles using a range of hydrophobic monomers via seeded RAFT aqueous emulsion...

Dynamic covalent chemistry has been exploited to prepare numerous examples of adaptable polymeric materials that exhibit unique properties. Herein, the chemical adsorption of aldehyde-functional diblock copolymer spherical nanoparticles onto amine-functionalized surface-grafted polymer brushes via dynamic Schiff base chemistry is demonstrated. Init...

Seeded heteroepitaxial growth is a “living” crystallization-driven self-assembly (CDSA) method that has emerged as a promising route to create uniform segmented nanoparticles with diverse core chemistries by using chemically distinct core-forming polymers. Our previous results have demonstrated that crystallization kinetics is a key factor that det...

The reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion polymerization of 4-hydroxybutyl acrylate (HBA) is conducted using a water-soluble RAFT agent bearing a carboxylic acid group. This confers charge stabilization when such syntheses are conducted at pH 8, which leads to the formation of polydisperse anionic PHBA latex par...

With the purpose of investigating new polymeric materials as potential flow modifiers for their future application in enhanced oil recovery (EOR), a series of amphiphilic poly(di(ethylene glycol) methyl ether methacrylate-co-oligo(ethylene glycol) methyl ether methacrylate) [P(DEGMA-co-OEGMA)]-based core-shell nanoparticles were prepared by aqueous...

Two series of behenyl methacrylate-based diblock and statistical copolymers have been prepared by reversible addition–fragmentation chain transfer (RAFT) solution polymerization in n-dodecane and evaluated as additives for the crystal habit modification of a model wax (n-octacosane). DSC studies indicated that each statistical copolymer exhibited a...

We report the synthesis of redox- and pH-sensitive block copolymer micelles that contain chiral cores composed of helical poly(aryl isocyanide)s. Pentafluorophenyl (PFP) ester-containing micelles synthesised via nickel-catalysed coordination polymerisation-induced self-assembly (NiCCo-PISA) of helical poly(aryl isocyanide) amphiphilic diblock copol...

Proteins and peptides, built from precisely defined amino acid sequences, are an important class of biomolecules that play a vital role in most biological functions. Preparation of nanostructures through functionalization of natural, hydrophilic proteins/peptides with synthetic polymers or upon self-assembly of all-synthetic amphiphilic copolypept(...

The ability to tune the behavior of temperature-responsive polymers and self-assembled nanostructures has attracted significant interest in recent years, particularly in regard to their use in biotechnological applications. Herein, well-defined poly(2-(diethylamino)ethyl methacrylate) (PDEAEMA)-based core–shell particles were prepared by RAFT-media...

The self-assembly of amphiphilic block copolymers has facilitated the preparation of a wide variety of nano-objects of diverse morphology. Ready access to these nanostructures has opened up new possibilities in catalysis, sensing, and nanomedicine. In comparison, the self-assembly of large building blocks (i.e., amphiphilic bottlebrush polymers) ha...

Aqueous ring-opening metathesis polymerization (ROMP) is a powerful tool for polymer synthesis under environmentally friendly conditions, functionalization of biomacromolecules, and preparation of polymeric nanoparticles via ROMP-induced self-assembly (ROMPISA). Although new water-soluble Ru-based metathesis catalysts have been developed and evalua...

The development of controlled/living polymerization methodologies has underpinned a rapid expanse in our understanding of amphiphilic block copolymer self-assembly. In solution, amphiphilic block copolymers spontaneously organize to form a diverse set of nano-objects, such as spherical and worm-like micelles or vesicles, that have proven to be exce...

Understanding, predicting, and controlling the self-assembly behavior of stimuli-responsive block copolymers remains a pertinent challenge. As such, the copolymer blending protocol provides an accessible methodology for obtaining a range of intermediate polymeric nanostructures simply by blending two or more block copolymers in the desired molar ra...

The interest in helix-containing nanostructures is currently growing as a consequence of their potential applications in areas such as nanomedicine, nanomaterial design, chiral recognition, and asymmetric catalysis. Herein, we present a facile and tunable one-pot methodology to achieve chiral nano-objects. The nickel-catalyzed coordination polymeri...

Macromolecular architecture has an important role in the self-assembly process of block copolymer amphiphiles. Herein, two series of stimuli-responsive amphiphilic 3-miktoarm star hybrid terpolypeptides and their corresponding linear analogues were synthesized and exhibited the same overall composition and molecular weight but different macromolecu...

Polymerization-induced self-assembly (PISA) has simplified the preparation of polymeric nanoparticles, expanding their commercial importance. Recently, PISA mediated via ring-opening metathesis polymerization (ROMPISA) has emerged as a powerful alternative to existing PISA methodologies. ROMPISA can be conducted under air in minutes, producing uniq...

Aqueous polymerization-induced self-assembly (PISA) is a well-established methodology enabling in situ synthesis of polymeric nanoparticles of controllable morphology. Notably, PISA via ring-opening metathesis polymerization (ROMPISA) is an emerging technology for block copolymer self-assembly, mainly due to its high versatility and robustness. How...

Cylinders are fascinating structures with uniquely high surface area, internal volume, and rigidity. On the nanoscale, a broad range of applications have demonstrated advantageous behavior of cylindrical micelles or bottlebrush polymers over traditional spherical nano-objects. In the past, obtaining pure samples of cylindrical nanostructures using...

Poly(sarcosine) (PSar) is a non-ionic hydrophilic poly(peptoid) with numerous biologically relevant properties, making it an appealing candidate for the development of amphiphilic block copolymer nanostructures. In this work, the fabrication of poly(sarcosine)-based diblock copolymer nano-objects with various morphologies via aqueous reversible add...

We report an in silico method to predict monomers suitable for use in polymerization‐induced self‐assembly (PISA). By calculating the dependence of LogPoct/SA on the length of the growing polymer chain, the change in hydrophobicity during polymerization was determined. This allowed for evaluation of the capability of a monomer to polymerize to form...

We report an in silico method to predict monomers suitable for use in polymerization‐induced self‐assembly (PISA). By calculating the dependence of LogPoct/SA on the length of the growing polymer chain, the change in hydrophobicity during polymerization was determined. This allowed for evaluation of the capability of a monomer to polymerize to form...

Photoinitiated polymerization-induced self-assembly (photo-PISA) is an efficient approach to predictably prepare polymeric nanostructures with a wide range of morphologies. Given that this process can be performed at high concentrations and under mild reaction conditions, it has the potential to have significant industrial scope. However, given tha...

The preparation of a functional fluorine‐containing block copolymer using reversible addition–fragmentation chain‐transfer dispersion polymerization in DMSO as a “platform/scaffold” is explored. The nanostructures, comprised of poly(ethyleneglycol)‐b‐poly(pentafluorophenyl methacrylate) or PEG‐b‐P(PFMA), are formulated via photo‐initiated polymeriz...

Water‐soluble and amphiphilic polymers are of great interest to industry and academia, as they can be used in applications such as biomaterials and drug delivery. Whilst ring‐opening metathesis polymerization (ROMP) is a fast and functional group tolerant methodology for the synthesis of a wide range of polymers, its full potential for the synthesi...

Water‐soluble and amphiphilic polymers are of great interest to industry and academia, as they can be used in applications such as biomaterials and drug delivery. Whilst ring‐opening metathesis polymerization (ROMP) is a fast and functional group tolerant methodology for the synthesis of a wide range of polymers, its full potential for the synthesi...

Enzyme loading of polymersomes requires permeability to enable them to interact with the external environment, typically requiring addition of complex functionality to enable porosity. Herein, we describe a synthetic route toward intrinsically permeable polymersomes loaded with functional proteins using initiator-free visible light-mediated polymer...

A series of novel multi-responsive disulfide cross-linked polypeptide nanogels has been synthesized by a one-step ring-opening polymerization process. The pH-responsive core of the prepared nanogels was based on poly(L-histidine), the difunctional N-carboxy anhydride of L-cystine (L-Cys-NCA) was used as a reduction-cleavable cross-linking agent, wh...

The design and synthesis of novel poly(L-histidine)-grafted mesoporous silica nanoparticles (MSNs) by a surface-initiated ring-opening polymerization process (ROP) is reported. Using (3-aminopropyl)triethoxysilane (APTES) to introduce primary amino groups onto the MSN outer surface that work as ROP initiators, the nanoparticles were decorated with...