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Tissue engineering constitutes the most promising method of severe peripheral nerve injuries treatment and is considered as an alternative to autografts. To provide appropriate conditions during recovery special biomaterials called nerve guide conduits are required. An ideal candidate for this purpose should not only be biocompatible and protect newly forming tissue but also promote the recovery process. In this article a novel, multilayered biomaterial based on polyvinylpyrrolidone, collagen and chitosan of gradient structure modified with conductive nanoparticles is presented. Products were obtained by the combination of electrospinning and electrospraying techniques. Nerve guide conduits were subjected to FT-IR analysis, morphology and elemental composition study using SEM/EDS as well as biodegradation. Furthermore, their effect on 1321N1 human cell line was investigated by long-term cell culture. Lack of cytotoxicity was confirmed by XTT assay and morphology study. Obtained results confirmed a high potential of newly developed biomaterials in the field of nerve tissue regeneration with a special focus on injured nerves recovery. [ABSTRACT FROM AUTHOR]

In this study, liposomes coated with novel multifunctional polymers were proposed as an innovative platform for tumor targeted drug delivery. Novel Folic acid–Cysteine-Thiolated chitosan (FTC) derivatives possessing active targeting ability and redox responsivity were synthesized, characterized, and employed to develop FTC-coated liposomes. Liposomes were characterized for size, surface charge and drug encapsulation efficiency before and after coating. The formation of a coating layer on liposomal surface was confirmed by the slight increase in particle size and by zeta-potential changes. FTC-coated liposomes showed a redox-dependent drug release profile: good stability at physiological conditions and rapid release of liposome-entrapped calcein in presence of glutathione. Moreover, the uptake and cytotoxic activity of doxorubicin-loaded FTC-coated liposomes was evaluated on murine B16-F10 and human SKMEL2 melanoma cancer cells. Results demonstrated enhanced uptake and antitumor efficacy of FTC-coated liposomes compared to control chitosan-coated liposomes in both cancer lines, which is attributed to higher cellular uptake via folate receptor-mediated endocytosis and to triggered drug release by the reductive microenvironment of tumor cells. The proposed novel liposomes show great potential as nanocarriers for targeted therapy of cancer. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites are a class of composite materials containing polymer continuous phase as matrix and inorganic nanoparticles as fillers. Combining the advantages of both polymer and nanofillers, polymer nanocomposites can yield some desirable functionalities that cannot be achieved by the individual components, thus exhibiting tremendous potential for a variety of applications. However, their performances markedly depend on the dispersion and distribution of nanofillers in the polymer matrix. Recently, in situ emulsion polymerization has been demonstrated to be a powerful approach for the preparation of multifunctional polymer nanocomposites with good dispersion and homogeneous distribution of nanofillers. In this review, the fundamentals of polymer nanocomposites and their preparation strategies are briefly discussed, and then are comprehensively summarized recent advances in the design, preparation, functionalization, and applications of polymer nanocomposites via in situ emulsion polymerization. The particular focus is placed on the strategies for achieving homogeneous and good dispersion of nanofillers within polymer matrixes. Moreover, the current challenges and future opportunities of in situ emulsion polymerization to polymer nanocomposites are discussed to motivate future contributions and explore new possibilities. [ABSTRACT FROM AUTHOR]

In this study, liposomes coated with novel multifunctional polymers were proposed as an innovative platform for tumor targeted drug delivery. Novel Folic acid–Cysteine-Thiolated chitosan (FTC) derivatives possessing active targeting ability and redox responsivity were synthesized, characterized, and employed to develop FTC-coated liposomes. Liposomes were characterized for size, surface charge and drug encapsulation efficiency before and after coating. The formation of a coating layer on liposomal surface was confirmed by the slight increase in particle size and by zeta-potential changes. FTC-coated liposomes showed a redox-dependent drug release profile: good stability at physiological conditions and rapid release of liposome-entrapped calcein in presence of glutathione. Moreover, the uptake and cytotoxic activity of doxorubicin-loaded FTC-coated liposomes was evaluated on murine B16-F10 and human SKMEL2 melanoma cancer cells. Results demonstrated enhanced uptake and antitumor efficacy of FTC-coated liposomes compared to control chitosan-coated liposomes in both cancer lines, which is attributed to higher cellular uptake via folate receptor-mediated endocytosis and to triggered drug release by the reductive microenvironment of tumor cells. The proposed novel liposomes show great potential as nanocarriers for targeted therapy of cancer.

Polymeric materials have a broad range of mechanical and physical properties. They have been widely used in material science, biomedical engineering, chemical engineering, and mechanical engineering. The introduction of active elements into the soft matrix of polymers has enabled much more diversified functionalities of polymeric materials, such as self-healing, electroactive, magnetosensitive, pH-responsive, and many others. To further enable applications of these multifunctional polymers, a mechanistic modeling method is required and of great significance, as it can provide links between materials' micro/nano-structures and their macroscopic mechanical behaviors. Towards this goal, molecular simulation plays an important role in understanding the deformation and evolution of polymer networks under external loads and stimuli. These molecular insights provide physical guidance in the formulation of mechanistic-based continuum models for multifunctional polymers. In this perspective, we present a molecular simulation-guided and physics-informed modeling framework for polymeric materials. Firstly, the physical theory for polymer chains and their networks is briefly introduced. It serves as the foundation for mechanistic-models of polymers, linking their chemistry, physics, and mechanics together. Secondly, the deformation of the polymer network is used to derive the strain energy density functions. Thus, the corresponding continuum models can capture the intrinsic deformation mechanisms of polymer networks. We then highlight several representative examples across multiphysics coupling problems to describe in detail for this proposed framework. Last but not least, we discuss potential challenges and opportunities in the modeling of multifunctional polymers for future research directions. [ABSTRACT FROM AUTHOR]

A quinoxaline (Qx) and benzodithiophene (BDT) comprising of random copolymers, namely poly(5‐(6‐(5‐(4,8‐bis((2‐ethylhexyl)oxy)benzo[1,2‐b:4,5‐b′]dithiophen‐2‐yl)‐4‐(2‐ethylhexyl)thiophen‐2‐yl)‐4,8‐bis ((2‐ethylhexyl)oxy)benzo[1,2‐b:4,5‐b′]dithiophen‐2‐yl)‐2,3‐bis(3,4‐bis(octyloxy)phenyl)quinoxaline) (PQBT), is synthesized via Stille polycondensation reaction. To investigate the effect of the π‐bridge on the electrochromic properties, 3‐(2‐ethylhexyl) thiophene is incorporated the between Qx and BDT moiety. The resulting random copolymer is characterized by NMR spectroscopy, gel permeation chromatography (GPC), attenuated total reflectance−Fourier‐transform infrared spectroscopy (ATR−FTIR), and scanning electron microscopy (SEM). PQBT exhibits ambipolar and multichromic characteristics and is highly soluble in common solvents. Optoelectronic studies reveal two well‐separated absorption bands having maxima at 500 and 532 nm with 1.83 eV optical band gap (Egop). PQBT exhibits orange color in the neutral state with brown, green, and blue colors in the intermediate, oxidized, and reduced states, respectively. Subsequently, a PQBT and poly‐3,4‐ethylenedioxythiophene (PEDOT)‐bearing prototype bilayer electrochromic device working between orange and blue colors is constructed and characterized. [ABSTRACT FROM AUTHOR]

An overview of recent developments in the chemistry of synthesized multifunctional epoxy polymers and their composites is presented in this paper. The resins or different reactive precursors are flame retardant, thanks to the presence of phosphorus, sulfur and nitrogen. They can be used alone or be added in bulk to the polymers, to increase their properties (thermal, mechanical, flame retardant, electrical, dielectric, anticorrosive, viscosimetric, viscoelastic, rheological, etc.).In this review, we present synthetic strategies that have been put in place to functionalize the different spacer arms. [ABSTRACT FROM AUTHOR]

In the article, groups of multifunctional polymers used in drug dosage form technology were classified and evaluated. These compounds, in addition to their basic function as excipients, may have additional properties, e.g. stimuli sensitivity, enzyme inhibition, intestinal epithelium penetration enhancement, efflux pump inhibition, taste-masking, pharmacological activity and the ability to interact with enzymes responsible for drug metabolism. While classifying specific groups of multifunctional polymers, special emphasis was placed on the advantages of using them when designing new drug. Such advantages include, i.a., increasing substance bioavailability, improving substance stability during formulation and the possibility of obtaining forms of controlled or localized release to a specific site in the organism.

Abstract: Two conjugated polymers based on diketopyrrolopyrrole (DPP) in the main chain with different content of perylene bisimide (PBI) side chains are developed. The influence of PBI side chain on the photovoltaic performance of these DPP‐based conjugated polymers is systematically investigated. This study suggests that the PBI side chains can not only alter the absorption spectrum and energy level but also enhance the crystallinity of conjugated polymers. As a result, such polymers can act as electron donor, electron acceptor, and single‐component active layer in organic solar cells. These findings provide a new guideline for the future molecular design of multifunctional conjugated polymers. [ABSTRACT FROM AUTHOR]

Novel, multipurpose terpolymers based on styrene (PS), tert-butyl methacrylate (tBMA) and glycidyl methacrylate (GMA), have been synthesized via Atom Transfer Radical Polymerization (ATRP). Post-synthetic modification with 1-pyrenemethylamine (AMP) allows non-covalent functionalization of carbon nanotubes, eventually yielding a conductive nanocomposite materials capable of interacting with different Volatile Organic Compounds (VOCs) by electrical resistance variation upon exposure. Moreover, facile hydrolysis of the tBMA group yields polyelectrolytic macrosurfactants with remarkable thickening properties for promising applications in water solution, such as Enhanced Oil Recovery (EOR).

Multi walled carbon nanotubes (MWCNTs) and glycidyl polyhedral oligomeric silsesquioxanes (GPOSS) are common additives to enhance electrical conductivity and flame resistance of polymer resins, respectively. Yet, these additions may appreciably influence the mechanical behaviour of the polymers. In this work, the synergistic effect of MWCNTs and GPOSS on the fatigue behaviour of the polymer RTM6-2 was investigated. The results were discussed supported by scanning electron microscopy and energy dispersive spectroscopy analyses. By enhancing the polymer with MWCNTs, a slight decrease in the fatigue life is observed in the range of the low stress levels; however, it tends to coincide with the reference material at fatigue limit. The incorporation of the flame retardant GPOSS into the polymer enhanced with MWCNTs seems to have a significant deteriorating effect on the fatigue life. Scanning electron microscopy and energy dispersive spectroscopy investigation revealed MWCNTs and GPOSS agglomerations; they seem to act as defects leading to a degradation of the fatigue resistance. [ABSTRACT FROM AUTHOR]

In the article, groups of multifunctional polymers used in drug dosage form technology were classified and evaluated. These compounds, in addition to their basic function as excipients, may have additional properties, e.g. stimuli sensitivity, enzyme inhibition, intestinal epithelium penetration enhancement, efflux pump inhibition, taste-masking, pharmacological activity and the ability to interact with enzymes responsible for drug metabolism. While classifying specific groups of multifunctional polymers, special emphasis was placed on the advantages of using them when designing new drug. Such advantages include, i.a., increasing substance bioavailability, improving substance stability during formulation and the possibility of obtaining forms of controlled or localized release to a specific site in the organism. [ABSTRACT FROM AUTHOR]

Cardiovascular metallic stents established in clinical application are typically coated by a thin polymeric layer on the stent struts to improve hemocompatibility, whereby often a drug is added to the coating to inhibit neointimal hyperplasia. Besides such thin film coatings recently nano/microfiber coated stents are investigated, whereby the fibrous coating was applied circumferential on stents. Here, we explored whether a thin fibrous encasement of metallic stents with preferentially longitudinal aligned fibers and different local fiber densities can be achieved by electrospinning. An elastic degradable copolyetheresterurethane, which is reported to selectively enhance the adhesion of endothelial cells, while simultaneously rejecting smooth muscle cells, was utilized for stent coating. The fibrous stent encasements were microscopically assessed regarding their single fiber diameters, fiber covered area and fiber alignment at three characteristic stent regions before and after stent expansion. Stent coatings with thicknesses in the range from 30 to 50 µm were achieved via electrospinning with 1,1,1,3,3,3-hexafluoro-2-propanol (HFP)-based polymer solution, while a mixture of HFP and formic acid as solvent resulted in encasements with a thickness below 5 µm comprising submicron sized single fibers. All polymeric encasements were mechanically stable during expansion, whereby the fibers deposited on the struts remained their position. The observed changes in fiber density and diameter indicated diverse local deformation mechanisms of the microfibers at the different regions between the struts. Based on these results it can be anticipated that the presented fibrous encasement of stents might be a promising alternative to stents with polymeric strut coatings releasing anti-proliferative drugs. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study was to create a novel multifunctional polymer by covalent attachment of l -cysteine to the polymeric backbone of hydrophobically modified cross-linked poly(acrylic acid) (AC1030). Secondly, the free thiol groups of the resulting thiomer were activated using 2-mercaptonicotinic acid (2-MNA) to provide full reactivity and stability. Within this study, 1167.36 μmol cysteine and 865.72 μmol 2-MNA could be coupled per gram polymer. Studies evaluating mucoadhesive properties revealed a 4-fold extended adherence time to native small intestinal mucosa for the thiomer (AC1030-cysteine) as well as an 18-fold prolonged adhesion for the preactivated thiomer (AC1030-Cyst-2-MNA) compared to the unmodified polymer. Modification of the polymer led to a higher tablet stability concerning the thiomer and the S-protected thiomer, but a decelerated water uptake could be observed only for the preactivated thiomer. Neither the novel conjugates nor the unmodified polymer showed severe toxicity on Caco-2 cells. Evaluation of emulsification capacity proofed the ability to incorporate lipophilic compounds like medium chain triglycerides and the preservation of the emulsifying properties after the modifications. According to these results thiolated AC1030 as well as the S-protected thiolated polymer might provide a promising tool for solid and semisolid formulations in pharmaceutical development. [ABSTRACT FROM AUTHOR]

The synthesis of polymers with various functional groups has always been the core of polymer chemistry. Traditionally, there are two approaches to prepare such polymers: i) preparing functional monomers first and then conducting polymerization to get target functional polymers; and ii) post-modification of a precursor polymer. Both methods unavoidably involve separation and purification of intermediate products, which is laborious and time-consuming. A one-pot synthesis strategy, which combines monomer preparation and controlled polymerization in just one reactor to generate well-defined polymers efficiently, is thus proposed. Recent advances in the one-pot synthesis of multifunctional polymers through a multicomponent system are provided in this article. [ABSTRACT FROM AUTHOR]

Shape-memory polymers (SMPs) are stimuli-sensitive materials capable of performing complex movements on demand, which makes them interesting candidates for various applications, for example, in biomedicine or aerospace. This trend article highlights current approaches in the chemistry of SMPs, such as tailored segment chemistry to integrate additional functions and novel synthetic routes toward permanent and temporary netpoints. Multiphase polymer networks and multimaterial systems illustrate that SMPs can be constructed as a modular system of different building blocks and netpoints. Future developments are aiming at multifunctional and multistimuli-sensitive SMPs. [ABSTRACT FROM AUTHOR]

This article reviews the use of multifunctional polymers founded on high-molecular weight poly(ethylene glycol) (PEG). The design of new PEG derivatives assembled in a dendrimer-like multimeric fashion or bearing different functionalities on the same molecule is described. Their use as new drug delivery systems based on the conjugation of multiple copies or diversely active drugs on the same biocompatible support is illustrated. [ABSTRACT FROM AUTHOR]

Abstract: A flow type quartz crystal microbalance (QCM) chemical sensor was developed for monitoring heavy metal ions in aqueous solutions (that is suitable for environmental monitoring). The sensor is based upon surface chelation of the metal ions at multifunctional polymer modified gold electrodes on 9MHz AT-cut quartz resonators, functioning as a QCM. New processes have been developed which enable to obtain surface-modified gold electrodes with high heavy metal ions complexing ability. These polymer grafted QCM sensors can selectively adsorb heavy metal ions, such as copper, lead, chrome and cadmium, from solution over a wide range from 0.01 to 1000ppm concentration by complexation with functional groups in the polymers. Cations typically present in natural water did not interfere with the detection of heavy metals. X-Ray Reflectivity (XRR) and Total Reflection X-ray Fluorescence (TXRF) were carried out to characterise the unmodified and modified gold surfaces as well as to verify the possibility to selectively bond and remove metal ions. [Copyright &y& Elsevier]

The article discusses a study related to the trend of moving from permanent metals to degradable, multifunctional polymer or metallic implants with reference to coronary stents. It highlights improvement in implementation of drug-eluting stents (DES). It also highlights requirements for biodegradable stents (BDS) such as ability to release drugs in a timely- and concentration- controlled profile.

Abstract: The aim of this work is the development of vapor detectors formed from composites of conductive carbon black and insulating organic multifunctional polymers having metal ions complexing ability. The new materials are tailored to produce increased sensitivity toward specific classes of analyte vapors. For comparison purpose, poly(vinyl chloride) (PVC) with di(2-ethylhexyl)phthalate (DOP), a traditional low molecular weight plasticizer, is used as representative of the behavior of a traditional composite vapor detector. Resonant frequency shift of a quartz crystal microbalance (QCM) and dc resistance measurements have been performed simultaneously on polymer–carbon black composite materials. The proposed materials showed an enhanced sensitivity upon exposure to acetic acid and amines vapors; the performances of our systems are 103 times higher than those of a traditional composite vapor detector. Moreover the extent of such responses is beyond that expected by mass uptake upon exposure to the same vapors and cannot be attributed solely to differences in polymer/gas partition coefficients. In this respect, several different chemical factors determine the dc electrical response of this system: in our opinion changes in polymer conformation during the adsorption process also play a significant role. [Copyright &y& Elsevier]

Abstract: Pentafluorophenyl acrylate and -methacrylate were polymerized using AIBN as a thermal initiator. The obtained polymers were soluble polymeric active esters that could be used for the preparation of multifunctional polymers. The reactivity of poly(pentafluorophenylacrylate) and poly(pentafluorophenylmethacrylate) towards primary and secondary amines, as well as alcohols was investigated in a quantitative way. Both poly(active esters) reacted satisfactorily with aliphatic primary and secondary amines but only low conversion was found in the case of aromatic amines. Conversions of only 30% were reached when poly(pentafluorophenylacrylate) was treated with one equivalent of alcohol under base catalysis. In time resolved FT-IR studies the rate constants of the polymer analogous reactions were determined. [Copyright &y& Elsevier]

Amphoteric poly(amido-hydrazine)s (PAHYs) were obtained by hydrogen-transfer polyaddition of hydrazine, 1,2-dimethylhydrazine and 1,1-dimethylhydrazine to 2,2-bisacrylamidoacetic acid. These polymers were studied for biomedical applications, such as degradability in water solution, acid-base properties, and cell toxicity. They degraded rapidly in aqueous media under physiological conditions, their molecular weight was reduced to about one-fourth, that of the original polymer in less than two days. They exhibited a typical polyelectrolyte behavior with isoelectric points between 4 and 5 and are prevailingly anionic in the blood. In preliminary cell toxicity essays they proved to be remarkably biocompatible, comparable in this respect to amphoteric poly(amido-amine)s (PAAs), and much less toxic than poly-L-lysine and polyethylenimine. [ABSTRACT FROM AUTHOR]

Tumor blockade therapy is a promising penetration-independent antitumor modality, which effectively inhibits the exchange of nutrients, oxygen, and information between the tumor and surrounding microenvironments. However, the current blockade therapy strategies have limited antitumor efficacy due to defects of inadequate tumor obstruction, possible side effects, and short duration. For these reasons, a facilely synthesized versatile polymer 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-poly(ethylene glycol)-alendronate (DSPE-PEG-ALN, DPA) is developed to initiate the formation of biomineral shell around osteosarcoma as a potent physical barrier. The DSPE moiety shares a similar chemical structure with the cytomembrane, allowing the membrane insertion of DPA. The bisphosphonic acid groups in ALN attract ions to realize biomineralization around cells. After injection in the invasive osteosarcoma tissue, DPA inserts into the cytomembrane, induces continuous mineral deposition, and ultimately builds a physical barrier around the tumor. Meanwhile, ALN in DPA alleviates bone destruction by suppressing the activity of osteoclasts. Through hindering the exchange of necessary substances, the biomineralization coating inhibits the growth of primary osteosarcoma and pulmonary metastasis simultaneously. Therefore, the multifunctional polymer-initiating blockade therapy provides a promising modality for tumor inhibition in clinics with high efficacy and negligible side effects., (© 2022 Wiley-VCH GmbH.)

X-ray computed tomography (CT), as one of the most widely used noninvasive imaging modalities, can provide three-dimensional anatomic details with high resolution, which plays a key role in disease diagnosis and treatment assessment. However, although they are the most prevalent and FDA-approved contrast agents, iodinated water-soluble molecules still face some challenges in clinical applications, such as fast clearance, serious adverse effects, nonspecific distribution, and low sensitivity. Because of their high biocompatibility, tunable designability, controllable biodegradation, facile synthesis, and modification capability, the polymers have demonstrated great potential for efficient delivery of iodinated contrast agents (ICAs). Herein, we comprehensively summarized the applications of multifunctional polymeric materials for ICA delivery in terms of increasing circulation time, decreasing nephrotoxicity, and improving the specificity and sensitivity of ICAs for CT imaging. We mainly focused on various iodinated polymers from the aspects of preparation, functionalization, and application in medical diagnosis. Future perspectives for achieving better imaging and clinical translation are also discussed to motivate new technologies and solutions.

[Display omitted] • Multifunctional polydiallyl malonylurea was readily prepared. • The performance in coordination and supramolecular chemistries was demonstrated. • Coordination complexes of polydiallyl malonylurea with Ag+ exhibited antibacterial activity. • Supramolecular assembly with melamine can form regular structures of nanorods. The development of new polymers for coordination and supramolecular assemblies has emerged as an area of intensive research. The malonylurea-based compounds with five potential binding sites are versatile polyfunctional ligands in coordination and supramolecular chemistries. However, their significant potential in the form of polymer has rarely been explored. Inspired by diallyldimethy1ammonium chloride, a kind of malonylurea-contained monomer diallyl malonylurea (DAMU) was synthesized and used to readily prepare multifunctional polymer polydiallyl malonylurea (PDAMU) by free radical polymerization. The chain structure and composition as well as physicochemical properties of PDAMU were well characterized and investigated. Especially, the PDAMU as building blocks used in coordination and supramolecular chemistries was demonstrated to be able to not only coordinate with silver ions (Ag+) to form complexes (PDAMU-Ag) with high antibacterial activity, but also produce supramolecular assemblies with regular morphology of nanorods via complementary hydrogen bonds with melamine. These results indicated that the PDAMU bearing malonylurea groups can serve as useful platform for fabrication of coordination complexes and supramolecular assemblies, exhibiting great potential in the construction of drug design and molecular receptors, which are expected to expand the methodological scope and application range of malonylurea-contained polymers. [ABSTRACT FROM AUTHOR]

Novel, multipurpose terpolymers based on styrene (PS), tert-butyl methacrylate (tBMA) and glycidyl methacrylate (GMA), have been synthesized via Atom Transfer Radical Polymerization (ATRP). Post-synthetic modification with 1-pyrenemethylamine (AMP) allows non-covalent functionalization of carbon nanotubes, eventually yielding a conductive nanocomposite materials capable of interacting with different Volatile Organic Compounds (VOCs) by electrical resistance variation upon exposure. Moreover, facile hydrolysis of the tBMA group yields polyelectrolytic macrosurfactants with remarkable thickening properties for promising applications in water solution, such as Enhanced Oil Recovery (EOR). [ABSTRACT FROM AUTHOR]

Front Cover: Shape‐memory polymers can be created in a modular approach, consisting of three components: chain segments, permanent netpoints and temporary netpoints. Varying these components enables the integration of several functions, as well as the implementation of multistimuli‐sensitivity in shape‐memory polymers. Further details can be found in the article by Konstanze K. Julich‐Gruner, Candy Löwenberg, Axel T. Neffe, Marc Behl, and Andreas Lendlein* on page 527. [ABSTRACT FROM AUTHOR]