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Encapsulation with polymers is a well-known strategy to stabilize and functionalize nanomaterials and tune their physicochemical properties. Amphiphilic copolymers are promising in this context, but their structural diversity and complexity also make understanding and predicting their behavior challenging. This is particularly the case in complex media which are relevant for intended applications in medicine and nanobiotechnology. Here, we studied the encapsulation of gold nanoparticles and quantum dots with amphiphilic copolymers differing in their charge and molecular structure. Protein adsorption to the nanoconjugates was studied with fluorescence correlation spectroscopy, and their surface activity was studied with dynamic interfacial tensiometry. Encapsulation of the nanoparticles without affecting their characteristic properties was possible with all tested polymers and provided good stabilization. However, the interaction with proteins and cells significantly depended on structural details. We identified statistical copolymers providing strongly reduced protein adsorption and low unspecific cellular uptake. Interestingly, different zwitterionic amphiphilic copolymers showed substantial differences in their resulting bio-repulsive properties. Among the polymers tested herein, statistical copolymers with sulfobetaine and phosphatidylcholine sidechains performed better than copolymers with carboxylic acid- and dimethylamino-terminated sidechains. [ABSTRACT FROM AUTHOR]

Comb‐shape, block copolymers from hydrophilic poly(ethylenglycol) monomethyl ether acrylate (mPEGA, A) and hydrophobic 2‐ethylhexyl acrylate (EHA, B) are synthesized by copper(0)‐mediated single‐electron transfer living radical polymerization (SET‐LRP) via sequential addition of the two monomers, resulting in different compositions (AB, ABA, BAB, BA), molar masses, and mPEGA/EHA ratios. All polymers show narrow molar mass distributions and molecular weights of 7.7–25.50 kg mol−1, demonstrating precise control over the polymerization and molecular weights through the utilization of SET‐LRP. Kinetic experiments are conducted to investigate the polymerization behavior of mPEGA and EHA in N,N‐dimethylformamide as a rather uncommon solvent for SET‐LRP further underlining a living‐type polymerization. Amphiphilic properties are investigated by critical micelle concentration (CMC) measurements and formation of micelles in water. A reverse relation between mPEGA/EHA ratio and CMC values reveals that an increased hydrophobicity leads to decreased CMC values. The self‐assembly behavior of polymers in water confirms the formation of uniform and stable micelles in water with a size between 12 and 184 nm depending on the composition of the polymers. With increased hydrophilicity, micelle sizes increase as well. In vitro tests of the obtained polymers show excellent biocompatibility even at high concentrations further affirming their suitability for drug delivery applications. [ABSTRACT FROM AUTHOR]

Amphiphilic fluorinated copolymers PEGMAx‐co‐FAy and TEGMAx‐co‐FAy are prepared by activators regenerated by electron transfer atom transfer radical polymerization (ARGET‐ATRP). All polymers present a reversible thermoresponsive lower critical solution temperature‐type behavior, and a cloud point temperature (Tc) in the range of 30–60 °C strictly dependent on the length of the oxyethylene side chain, the content of the hydrophobic counits, and the concentration of the solution. Combined small angle X‐ray scattering (SAXS) and dynamic light scattering measurements are used to study the self‐assembly behavior in water, organic solvents (tetrahydrofuran [THF] and dimethylformamide [DMF]), and a fluorinated solvent (hexafluorobenzene [HFB]). SAXS confirms the formation of compact‐globular single‐chain self‐folded unimer micelles in water below Tc, which generally presents small hydrodynamic diameters (Dh ≤ 8 nm) as a result of the folding of the hydrophobic perfluorohexylethyl acrylate counits. The copolymers are also able to form reverse unimer micelle in HFB. The copolymers are not able to self‐assemble in unimer micelles in THF or DMF solutions, in which they adopt conventional random coil conformations. [ABSTRACT FROM AUTHOR]

Semiconducting polymers with amphiphilic properties can play an increasing role in future organic and unimolecular electronic devices, especially due to their excellent processability and ease of self-assembly into thin films, but they could also be used as intermediate layers to improve electron transport in metal-organic junctions. In this work, we synthesized a homologous series of amphiphiles by copolymerization of aniline with aniline-N-propanesulfonic acid. The polymerization was first initiated with aniline, and the latter monomer was added at different time intervals: 2, 10, 20, 30, 40, and 60 min, spaced from the time of initiation. Thus, the poly(aniline-co-aniline-N-propanesulfonic acid) (PANi-co-PANs) homologous series of copolymers obtained had the same length of the water soluble PANs chain, and a variable length of the water insoluble PANi chain. We demonstrated that there is a strong structure–activity relationship in the homologous series of PANi-co-PANs copolymers, evidenced in the tensiometry and wettability studies, as well as in-depth conductivity with frequency and temperature investigations. We observed a gradual change in solubility, interfacial activity, and conductivity in the homologous series of amphiphiles within the boundaries set by the electrically insulating, hydrophilic PANs chain and the semiconducting, hydrophobic PANi chains; representing a viable platform toward designing polymers with tunable conductivity. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymer molecular brushes of three different types with side chains consisting of alkyl and oligo(ethylene glycol) blocks based on higher alkoxy oligo(ethylene glycol) methacrylates (HAOEGM), methoxy oligo(ethylene glycol) methacrylates (MOEGM) and dodecyl(meth)acrylate have been successfully synthesized via conventional radical polymerization in toluene. In case of the copolymerization of HAOEGM with MOEGM, the monomer reactivity ratios were independent of the structure of higher alkyl groups (C12–C18) and the degree of ethoxylation (n = 6–11) and were equal to 0.76–0.81 and 1.19–1.27, respectively. In case of the copolymerization of HAOEGM or MOEGM with dodecyl methacrylate, the reactivity ratios were even closer to each other (1.00–1.17). Applicability of the reactivity ratios calculated at low conversions for estimating copolymer compositions at high conversions was shown. In all systems, compositionally homogeneous copolymers with a narrow molecular weight distribution were formed. For the HAOEGM (C12, n = 9)—dodecyl acrylate monomer system, the reactivity ratios were 0.88 and 0.25 and the resulting copolymers had high compositional heterogeneity. [ABSTRACT FROM AUTHOR]

Amphiphilic coatings have garnered significant attention in the realm of fouling resistance due to their potential to reduce fouling adhesion and enhance fouling release. However, developing anti-fouling amphiphilic surfaces with robust mechanical properties remains a formidable challenge. Herein, a series of norbornene-based amphiphilic copolymers (PNPFE-PEG-x) with varying NPEG mass fractions (0–50 wt%) were well-designed and fabricated via living ring-opening metathesis polymerization (ROMP) employing norbornene-based fluorinated monomer (NPFE) and poly(ethylene glycol) (NPEG) monomer. The water absorption, surface wettability, and mechanical properties of the amphiphilic copolymers can be regulated by adjusting the NPEG contents. Particularly, dry PNPFE-PEG-10 % films exhibited exceptional tensile strength of 14.36 MPa and breaking elongation of 376 %. The wet PNFPE-PEG-H 2 O samples exhibited a unique hydration-induced stiffening phenomenon. Even in the water swelling state, wet PNPFE-PEG-50 % films still demonstrated remarkable tensile strength of 8.05 MPa and breaking elongation of 74.81 %. Furthermore, increasing the NPEG content effectively resisted bovine serum albumin and fibrinogen protein adsorption on the coatings, with PNPFE-PEG-50 % showing the lowest protein adsorption at 19 μg/cm2 and 27 μg/cm2, respectively, indicating excellent anti-fouling properties. In addition, PNPFE-PEG-x exhibited anti-icing property through rational molecular design. These high-performance anti-fouling coatings are equipped to meet diverse application needs in marine anti-fouling, biomedical instruments, and other relevant fields. [Display omitted] • Well-designed norbornene-based amphiphilic copolymers prepared by ROMP polymerization • Amphiphilic polymers with simultaneous mechanical robustness and fouling resistance • Possessing anti-icing property through rational molecular design [ABSTRACT FROM AUTHOR]

A series of readily available, amphiphilic pyrene‐ and perylene‐containing fluorescent materials, derived from the co‐polymerisation of 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid with acrylate esters, can be used to detect heavy metal ions in the micromolar concentration range in aqueous solutions. The incorporation of these amphiphilic copolymers into semi‐interpenetrating hydrogels also resulted in the irreversible removal of divalent Co2+, Ni2+, Cu2+ and Pb2+ ions from aqueous solutions at neutral pH. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new renewable monomer, 10,11-dihydroxyundecanoic acid, is described. • Hyperbranched hydroxypolyesters were obtained by self-polycondensation using CALB. • Amphiphilic copolyesters with methoxypolyethylenglycol were prepared. • mPEG carboxylic acid derivatives were grafted onto the hydroxypolyesters. • Self-assembly of amphiphilic polyesters form multimolecular micelles of 100–300 nm. Abstract The synthesis of a partially renewable hydroxyl hyperbranched polyester: poly(10,11-dihydroxyundecanoic acid) (PDHU), by polycondensation using CALB as catalyst, has been described. The synthesized polymers were structurally characterized in detail, using model compounds previously synthesized, by 1H, 13C and 19F NMR. The synthesis of amphiphilic copolymers by incorporation of mPEG moieties and utilizing CALB, was carried using two methods: by copolymerization of mPEG-OH and 10,11-dihydroxyundecanoic to produce block hyperbranched copolymers, and grafting onto hydroxyl groups of linear and hyperbranched PDHU, mPEG containing carboxylic acid. The microstructure of block and grafted copolymers was determined in detail by NMR spectroscopy by using models and 1H-13C heteronuclear bidimensional correlations. The self-assembly of these amphiphilic polyesters form well-defined multimolecular micelles ranging 100–300 nm in very diluted aqueous solutions, showing potential application in drug delivery among other applications. [ABSTRACT FROM AUTHOR]

The mixing Gibbs energy Dgm for the flower-micelle phase of amphiphilic random and periodic (including alternating) copolymers was formulated on the basis of the lattice model. The formulated Dgm predicts (1) the inverse proportionality of the aggregation number to the degree of polymerization of the copolymer, (2) the increase of the critical micelle concentration with decreasing the hydrophobe content, and (3) the crossover from the micellization to the liquid-liquid phase separation as the hydrophobe content increases. The transition from the uni-core flower micelle to the multi-core flower necklace as the degree of polymerization increases was also implicitly indicated by the theory. These theoretical results were compared with experimental results for amphiphilic random and alternating copolymers reported so far. [ABSTRACT FROM AUTHOR]

An efficient strategy for engineering nanostructured surfaces by coupling soft polymeric nanoarchitectures to functionalized surfaces is presented. Self-assembly of polymeric nanoarchitectures from amphiphilic triblock copolymers can yield both filled and hollow spherical nanoarchitectures, depending on the properties of the polymer chosen. These nanoarchitectures are immobilized on solid substrates via a biocompatible thiol-ene reaction, and conditions are optimized to maintain structural integrity of polymeric assemblies. Two routes of surface modification are also implemented to allow inclusion of a polymeric spacer that can mediate between soft polymeric assemblies and solid substrates. Nanostructured surfaces with both filled and hollow nanoarchitectures attached to the surface directly or with a spacer are successfully generated with this protocol. This concept of generating nanostructured surfaces using preassembled polymeric architectures is an important step toward active surfaces, because entrapment of active molecules in the nanoarchitectures prior to their immobilization opens the door to easy generation of surfaces with predetermined activities. [ABSTRACT FROM AUTHOR]

Once removed from their natural environment, membrane proteins depend on membrane-mimetic systems to retain their native structures and functions. To this end, lipid-bilayer nanodiscs that are bounded by scaffold proteins or amphiphilic polymers such as styrene/maleic acid (SMA) copolymers have been introduced as alternatives to detergent micelles and liposomes for in vitro membrane-protein research. Herein, we show that an alternating diisobutylene/maleic acid (DIBMA) copolymer shows equal performance to SMA in solubilizing phospholipids, stabilizes an integral membrane enzyme in functional bilayer nanodiscs, and extracts proteins of various sizes directly from cellular membranes. Unlike aromatic SMA, aliphatic DIBMA has only a mild effect on lipid acyl-chain order, does not interfere with optical spectroscopy in the far-UV range, and does not precipitate in the presence of low millimolar concentrations of divalent cations. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers consist of hydrophilic and hydrophobic monomer units have attracted great technological attention recently, owing to their unique properties and their ability to stabilize various interfaces in aqueous systems. This paper presents a novel and facile approach to produce spherical polyacrylamide, polystyrene and hydrophobically modified polyacrylamide (HM-PAM), as one of the most important type of amphiphilic copolymers, using a continuous aerosol-photopolymerization for the first time. To this end, the monomer droplets were generated by an atomizer, then photopolymerization was initiated ‘‘in flight’’ by ultraviolet (UV) irradiation of the aerosol monomer droplets containing photoinitiator within the average aerosol residence time of 30 s in the photoreactor. To control the aqueous solubility, size and morphology of the resulting HM-PAM copolymers, different styrene/acrylamide monomer concentrations were introduced to the system. The textural properties of the obtained materials were characterized by TEM, SEM and N 2 adsorption-desorption isotherms. The results revealed that the copolymers and polyacrylamide have cauliflower-like morphologies, while polystyrene has a nearly smooth morphology. Moreover, chemical compositions of the obtained materials were investigated by several characterization techniques such as 1 H NMR, FT-IR, TGA and elemental analysis. 1 H NMR and elemental analysis of resulting copolymers microstructures displayed successful incorporation of styrene in copolymer with a good agreement compared to initial ratios. The production of amphiphilic copolymer of acrylamide and styrene using the facile aerosol-photopolymerization method might open new avenues to produce various amphiphilic copolymers with a variety of hydrophobic and hydrophilic monomers with desirable properties. [ABSTRACT FROM AUTHOR]

The synthesis, micellar aggregation, and pH-triggered intracellular drug delivery ability of an amphiphilic statistical copolymer (P2) are studied. Two methacrylate derivatives, one containing a hydrophilic pendant and the other containing a hydrophobic pendant chain, are copolymerized to produce P2. The hydrophobic pendant chain is linked to the polymer backbone by a β-thiopropionate linkage, known to undergo slow hydrolysis at mild acidic pH. P2 forms a multimicellar cluster in water with a critical aggregation concentration of 0.02 mg mL−1 and encapsulates a hydrophobic guest such as pyrene, Nile red, or the anti-cancer drug doxorubicin (Dox). Sustained release of the entrapped Dox (80% after 100 h) is noticed at pH 5.2, while release is significantly slower (35% after 100 h) at pH 7.4. Acidic hydrolysis of the β-thiopropionate linkage leading to the reduction of the hydrophobicity is established as the cause for micellar disassembly and triggered drug release. Cell-culture studies with the human breast cancer cell line, MCF-7, reveal biocompatibility of P2 (below 150 μg mL−1). It is further tested for intracellular delivery of Dox. MCF-7 cells remain healthy at pH 7.4 but become unhealthy at pH 5.2 when treated with a Dox-loaded P2 micelles. [ABSTRACT FROM AUTHOR]

In this study the effect of oxidative modification on micellar and drug delivery properties of copolymers of ethylene oxide (EO) and propylene oxide (PO) was investigated. Carboxylated trifunctional copolymers were synthesized in the reaction with chromium(VI) oxide. We found that carboxylation significantly improved the uniformity and stability of polymeric micelles by inhibiting the microphase transition. The cytotoxicity of copolymers was studied in relation to their aggregative state on two cell types (cancer line vs. primary fibroblasts). The accumulation of rhodamine 123 in neuroblastoma SH-SY5Y cells was dramatically increased in the presence of the oxidized block copolymer with the number of PO and EO units of 83.5 and 24.2, respectively. The copolymer was also tested as an enhancer for topical drug delivery to the spinal cord when applied subdurally. The oxidized copolymer facilitated the penetration of rhodamine 123 across spinal cord tissues and increased its intraspinal accumulation. These results show the potential of using oxidized EO/PO based polymers for non-invasive delivery of protective drugs after spinal cord injury. [ABSTRACT FROM AUTHOR]

The kinetic model of the amphiphilic copolymers with hyperbranched core and linear arms was developed for both semibatch and one-pot polymerization. The molecular size distribution functions of the species obtained and the various molecular parameters were analytically derived. The topological structures and molecular parameters of the products depend on initial mole feed ratios of the reactants. Under the same reaction conditions, the polydispersity index of the products resulted from semibatch is smaller than that of the one-pot process and there are more terminal units on the surface of hyperbranched macroinitiators from semibatch process. Accordingly, the topological structures of the amphiphilic hyperbranched copolymers and the successive self-assembly shapes can be designed by the suitable initial conditions of the polymerization. [ABSTRACT FROM AUTHOR]

Copolymers composed of acrylamide (AM), N-isopropylacrylamide (NIPAM), and a hydrophobic monomer, either N,N-dihexylacrylamide (DHAM) or N,N-dioctylacrylamide (DOAM), were synthesized using different monomer concentrations by micellar polymerization in aqueous media. Resulting polymers were characterized by molecular weight, final composition, lower critical solution temperature (LCST), and viscoelastic properties on steady-shear state. The effect of the addition of an anionic surfactant, sodium dodecyl sulphate (SDS), was studied in order to increase the viscosity of the solution. Dynamic rheological studies were conducted to achieve a better comprehension of the parameters affecting the viscoelastic behavior of the polymers. This study allows us to understand the relationship between the rheological behavior in aqueous solution with the relaxation time (T) and plateau modulus (G), taking into account the intra e inter-associations present in the multiblock copolymer (hydrophobic junctions) as well as the interaction between the anionic surfactant with the hydrophobic blocks and with the NIPAM units below and above the LCST of the aqueous system. [ABSTRACT FROM AUTHOR]

Highlights: [•] The synthesis of hyperbranched polymers is reviewed. [•] Examples of amphiphilic hyperbranched polymers are presented. [•] The potential of CCTP for the synthesis of hyperbranched polymers is highlighted. [ABSTRACT FROM AUTHOR]

Nanospheres and nanocapsules of an amphiphilic copolymer having methylated polyethylene glycol and hexadecyl lateral groups were prepared by the solvent displacement method and using confined impinging jet mixers. Degradation, thermal properties and crystalline structure were investigated. Interestingly, pegylated chains hydrolyzed through ester bond cleavage, whereas the more hydrophobic hexadecyl ester groups were resistant to degradation in aqueous media. The copolymer crystallized from the melt, giving rise to spherulites with a negative birefringence and domains corresponding to crystallization of the different lateral groups. Size distribution and morphology of nanoparticles were mainly evaluated by electron microscopy. Nanocapsules were characterized by a stable membrane with a thickness close to 5 nm that allowed efficient encapsulation of a triglyceride oil. Triclosan was selected as an example of a hydrophobic drug to be loaded in both nanospheres and nanocapsules. The release behavior of these dosage forms was clearly different. Thus, the Burst effect was practically suppressed when using nanocapsules; in addition, these showed a sustained, controlled release over a greater time period. Antimicrobial activity of triclosan loaded nanospheres and nanocapsules was evaluated using Gram-negative and Gram-positive bacteria. The former were highly sensitive to the released triclosan whereas the latter strongly depended on the number of particles in the culture medium. [ABSTRACT FROM AUTHOR]

Abstract: Polydiacetylene (PDA) is an excellent color-changing indicator. In this paper, we demonstrate a new and interesting kind of time–temperature chromatic sensor based on PDA vesicle and amphiphilic polymer. In presence of amphiphilic polymers, PDA vesicles could gradually transit from blue to red, which was irreversible and regularly depended on the temperature, time, and properties of amphiphilic polymer (including the concentration, molecular weight, molecular structure, hydrophobicity, and thermo-sensitive property). Higher concentration of amphiphilic polymers resulted in lower color-transition temperature and faster color-transition. Also, higher temperature led to faster color-transition. The color-changing of PDA/amphiphilic polymer matrix may have resulted from the higher temperature and gradual insertion of amphiphilic polymer into PDA, synergistically perturbing the conformation of PDA. The prepared PDA/F127, PDA/F68, PDA/L35 and PDA/Tween-20 aqueous matrix showed potential application in time–temperature chromatic sensors at around 10–50°C. This work provides a new method to design time–temperature chromatic sensors. [Copyright &y& Elsevier]

[Display omitted] • Porphyrin-cored amphiphilic star block copolymers were well synthesized via ATRP. • Hydrophobic polymer-type and block fraction were varied for hydrophobicity control. • More intensified hydrophobicity led to more efficient photooxidation of furfural. Pd-contained porphyrin-cored (P(Pd)) amphiphilic star block copolymers with a hydrophobic interior, including either poly(methyl methacrylate) (PMMA) or poly(dodecyl methacrylate) (PDMA), and poly(ethylene glycol) methyl ether methacrylate (PEGMA) hydrophilic outer layer were synthesized by Ru-catalyzed atom transfer radical polymerization (ATRP). The acquired starpolymer photocatalysts were examined for photooxidation of furfural. The starpolymers with the PDMA hydrophobic interior led to higher efficiency in the photooxidation of furfural than the starpolymers without hydrophobic interior and with the PMMA interior. In addition, the grater hydrophobic PDMA fraction exhibited a higher photooxidation efficiency. Those experimentally demonstrated the importance of the hydrophobic interior toward efficient photooxidation. We believe that this study provides a fundamental idea in developing amphiphilic star block copolymer photocatalysts. [ABSTRACT FROM AUTHOR]

Reversible addition‐fragmentation chain transfer polymerization was employed to synthesize a set of copolymers of styrene (PS) and 2,3,4,5,6‐pentafluorostyrene (PPFS), as well as block copolymers with tert‐butyl acrylate (PtBA)‐b‐PS‐co‐PPFS, with control over molecular weight and polydispersity. It was found that the copolymerization of styrene and PFS allowed for the preparation of gradient copolymers with opposite levels of monomer consumption, depending on the feed ratio. Conversion to amphiphilic block copolymers, PAA‐b‐(PS‐co‐PPFS), by removing the protecting groups was followed by fitting with monomethoxy poly(ethylene glycol) chains. Solution‐state assembly and intramicellar crosslinking afforded shell crosslinked knedel‐like (SCK) block copolymer nanoparticles. These fluorinated nanoparticles (ca. 20 nm diameters) were studied as potential magnetic resonance imaging (MRI) contrast agents based on the 19F‐nuclei; however, it was found that packaging of the hydrophobic fluorinated polymers into the core domain restricted the mobility of the chains and prohibited 19F NMR spectroscopy when the particles were dispersed in water without an organic cosolvent. Packing of perflouro‐15‐crown‐5‐ether (PFCE) into the polymer micelle was demonstrated with good uptake efficiency; however, it was necessary to swell the core with a good solvent (DMSO) to increase the mobility and observe the 19F NMR signal of the PFCE. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1023–1037, 2009 [ABSTRACT FROM AUTHOR]

A random copolymer of sodium 2-(acrylamido)-2-methylpropanesulfonate and sodium 11-acrylamidoundecanoate has been synthesized by random radical copolymerization. The resulting random copolymer forms a unimolecular (unimer) micelle in 0.1 M NaCl aqueous solutions at acidic pH values, whereas the unimer micelle was disrupted into an open chain conformation at basic pH values. At acidic pH values, the intrachain association of the protonated pendent alkyl carboxyl groups causes the polymer chain to form a unimer micelle. At basic pH values, the electrostatic repulsion between the pendent alkyl carboxylate anions causes the polymer chain to adopt an open chain conformation. The pH-induced reversible disruption and formation of a unimer micelle was characterized using light scattering, viscometry, ¹H NMR spin—spin relaxation time, and fluorescence techniques. Small hydrophobic molecules could be solubilized into the hydrophobic domain of the unimer micelle at low pH values. At high pH values, on the other hand, the hydrophobic molecules could be released upon disruption of the unimer micelle. [ABSTRACT FROM AUTHOR]

The request of new materials, matching strict requirements to be applied in precision and patient-specific medicine, is pushing for the synthesis of more and more complex block copolymers. Amphiphilic block copolymers are emerging in the biomedical field due to their great potential in terms of stimuli responsiveness, drug loading capabilities and reversible thermal gelation. Amphiphilicity guarantees self-assembly and thermoreversibility, while grafting polymers offers the possibility of combining blocks with various properties in one single material. These features make amphiphilic block copolymers excellent candidates for fine tuning drug delivery, gene therapy and for designing injectable hydrogels for tissue engineering. This manuscript revises the main techniques developed in the last decade for the synthesis of amphiphilic block copolymers for biomedical application. Strategies for fine tuning the properties of these novel materials during synthesis are discussed. A deep knowledge of the synthesis techniques and their effect on the performance and the biocompatibility of these polymers is the first step to move them from the lab to the bench. Current results predict a bright future for these materials in paving the way towards a smarter, less invasive, while more effective, medicine. [Display omitted] • Amphiphilic block copolymers: available synthesis routes and their advantages and disadvantages • Increased degree of complexity in polymer microstructures by combining synthesis techniques • Strategies to fine tune the properties of amphiphilic block copolymers • Biomedical applications: drug delivery, cancer treatment, tissue engineering, injectable hydrogels, imaging [ABSTRACT FROM AUTHOR]

A series of well-defined antimicrobial polymers composed of comonomers bearing thiazole ring (2-(((2-(4-methylthiazol-5-yl)ethoxy)carbonyl)oxy)ethyl methacrylate monomer (MTZ)) and non-hemotoxic poly(ethylene glycol) side chains (poly(ethylene glycol) methyl ether methacrylate (PEGMA)) were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. By post-polymerization functionalization strategy, polymers were quaternized with either butyl or octyl iodides to result in cationic amphiphilic copolymers incorporating thiazolium groups, thus with variable hydrophobic/hydrophilic balance associated to the length of the alkylating agent. Likewise, the molar percentage of PEGMA was modulated in the copolymers, also affecting the amphiphilicity. The antimicrobial activities of these cationic polymers were determined against Gram-positive and Gram-negative bacteria and fungi. Minimum inhibitory concentration (MIC) was found to be dependent on both length of the alkyl hydrophobic chain and the content of PEGMA in the copolymers. More hydrophobic octylated copolymers were found to be more effective against all tested microorganisms. The incorporation of non-ionic hydrophilic units, PEGMA, reduces the hydrophobicity of the system and the activity is markedly reduced. This effect is dramatic in the case of butylated copolymers, in which the hydrophobic/hydrophilic balance is highly affected. The hemolytic properties of polymers analyzed against human red blood cells were greatly affected by the hydrophobic/hydrophilic balance of the copolymers and the content of PEGMA, which drastically reduces the hemotoxicity. The copolymers containing longer hydrophobic chain, octyl, are much more hemotoxic than their corresponding butylated copolymers. [ABSTRACT FROM AUTHOR]

The combination of controlled anionic polymerization and subsequent introduction of hydrogen bonding groups was established to form thermo-reversible, supramolecular networks. Several polyisoprene-block-polystyrene-block-polyisoprene (ISI) copolymers—with polystyrene (PS) as the main block, and consequently giving the decisive material characteristics—were synthesized. The novel modification approach to post-functionalize the polyisoprene (PI) end-blocks and to introduce different motifs, which are able to form self-complementary hydrogen bonds, was attained. In the first step, hydroxylation was accomplished using 9-borabicyclo[3.3.1]nonane. Starting from the hydroxylated polymer, esterification with succinic anhydride was implemented to form an ester group with carboxylic end-group (-O-CO-CH2-CH2-COOH). In a second approach, 1,1'-carbonyldiimidazole was used as coupling agent to introduce various types of diamines (diethylenetriamine, triethylentetramine, and 2,6-diaminopyridine) to prepare urethane groups with amine end-group (-O-CO-NH-R-NH2). 1H NMR spectroscopy was used to confirm the successful synthesis and to calculate the degree of functionalization Df. Differential scanning calorimetry (DSC) showed a difference of the glass transition temperature Tg between unfunctionalized and functionalized block copolymers, but no greater influence between the different types of modification, and thus, on the Tg of the PS block. In temperature dependent FTIR spectroscopy, reversible processes were observed. [ABSTRACT FROM AUTHOR]