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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., MINECO, Agencia Estatal de Investigación (AEI, Spain), Fondo Europeo de Desarrollo Regional (FEDER, EU), Depto. de Química Orgánica, Fac. de Ciencias Químicas, TRUE, pub

We review the considerable progress during the recent decade in the endeavours of designing, optimising, and utilising carrier particle systems for structural and functional studies of membrane proteins in near-native environments. New and improved systems are constantly emerging, novel studies push the perceived limits of a given carrier system, and specific carrier systems consolidate and entrench themselves as the system of choice for particular classes of target membrane protein systems. This review covers the most frequently used carrier systems for such studies and emphasises similarities and differences between these systems as well as current trends and future directions for the field. Particular interest is devoted to the biophysical properties and membrane mimicking ability of each system and the manner in which this may impact an embedded membrane protein and an eventual structural or functional study.

We review the considerable progress during the recent decade in the endeavours of designing, optimising, and utilising carrier particle systems for structural and functional studies of membrane proteins in near-native environments. New and improved systems are constantly emerging, novel studies push the perceived limits of a given carrier system, and specific carrier systems consolidate and entrench themselves as the system of choice for particular classes of target membrane protein systems. This review covers the most frequently used carrier systems for such studies and emphasises similarities and differences between these systems as well as current trends and future directions for the field. Particular interest is devoted to the biophysical properties and membrane mimicking ability of each system and the manner in which this may impact an embedded membrane protein and an eventual structural or functional study.

Many of the amphiphilic molecules, or surfactants, are produced from fossil-based raw materials. With the increasing awareness of the climate situation, focus has shifted toward more environmentally friendly solutions to replace fossil-based products. This has led to more interest towards the forest. The circular bioeconomy is focused on making use of residues and waste and on optimizing the value of biomass over time via cascading. Nowadays, bark is seen as a waste product by industries and mainly incinerated as solid fuel. The bark contains interesting compounds but some of these are only available in low amounts, less than 1 % in the bark, while other components are present in several percentages. However, some of these components are potential candidates for the manufacture of amphiphiles and there seems to be a strong match between bark availability and surfactant demand. The global amount of bark available is approximately 359 million m3 and more than 10 million m3 of industrial bark are generated annually in Sweden and Finland. The bark of Norway spruce, Scots pine and silver birch contains approximately 25-32 % of extractives and part of these extractives has a potential as a surfactant backbone. This matches the global surfactant demand of about 15.6 million tons. Therefore, industrial bark has a significant potential value as a raw material source for amphiphilic molecules and polymers. This review focuses on betulin, condensed tannin and suberin. These compounds have been studied on individually and methods to extract them out from the bark are well investigated, but to utilize them as amphiphilic compounds has not been explored. With this review, we want to emphasis the potential of using bark, what today is seen as a waste product, as a raw material for production of amphiphiles. Moreover, a techno-economic analysis has been performed on betulin, tannins and suberin., QC 20230524

Aggregation-induced emission (AIE) is a phenomenon in which fluorescence is enhanced rather than quenched upon molecular assembly. AIE fluorogens (AIEgens) are flexible, conjugated systems that are limited in their dynamics when assembled, which improves their fluorescent properties. This intriguing feature has been incorporated in many different molecular assemblies and has been extended to nanoparticles composed of amphiphilic polymer building blocks. The integration of the fascinating AIE design principle with versatile polymer chemistry opens up new frontiers to approach and solve intrinsic obstacles of conventional fluorescent materials in nanoscience, including the aggregation-caused quenching effect. Furthermore, this integration has drawn significant attention from the nanomedicine community, due to the additional advantages of nanoparticles comprising AIEgenic molecules, such as emission brightness and fluorescence stability. In this regard, a range of AIEgenic amphiphilic polymers have been developed, displaying enhanced emission in the self-assembly/aggregated state. AIEgenic assemblies are regarded as attractive nanomaterials with inherent fluorescence, which display promising features in a biomedical context, for instance in biosensing, cell/tissue imaging and tracking, as well as (photo) therapeutics. In this review, we describe recent strategies for the design and synthesis of novel types of AIEgenic amphiphilic polymers via facile approaches including direct conjugation to natural/synthetic polymers, polymerization, post-polymerization and supramolecular host−guest interactions. Their self-assembly behavior and biomedical potential will be discussed.

We report the synthesis and solution properties of novel biobased thermoresponsive amphiphilic copolymers prepared using N,N-dimethyl lactamide acrylate (DMLA) and ethyl lactate acrylate (ELA) as hydrophilic and hydrophobic monomers, respectively. Copolymers with similar overall molecular weight but different monomer distribution profiles, such as random, diblock, triblock, and random-blocks, were prepared using photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization activated by a Zn-based photoredox catalyst. The synthesized polymers show interesting self-assembly and thermores-ponsive behavior in water, depending on the monomers distribution along the chain. Different critical solution temperatures, in the range of 13-70 degrees C, were observed by tuning the monomers molar ratio and distribution. The formation of aggregates of various types was proven by transmission electron microscopy (TEM). The prepared polymers also display different surface activity with the fully random copolymer being significantly more surface active than block systems. A study of emulsion stabilization was performed with oils of various polarity, showing promising results for applications of these novel polymers as biobased surfactants and water/oil (w/o) emulsion stabilizers.

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., Ministerio de Economía, Comercio y Empresa (España), Agencia Estatal de Investigación (España), Fondo Europeo de Desarrollo Regional, Depto. de Química Orgánica, Fac. de Ciencias Químicas, TRUE, pub

Chemical formulations, including surfactants, polymers, alkalis, or their combinations, are widely used in different oil recovery processes to improve water injection performance. However, based on challenging profit margins in most mature waterfloods in Colombia and overseas, it is necessary to explore alternatives that could offer better performance and greater operational flexibility than the conventional technologies used for enhanced oil recovery (EOR) processes. Polymeric surfactants are compounds widely used in the manufacture of domestic and industrial cleaning, pharmaceutical, cosmetic, and food products. These compounds represent an interesting alternative as they can simultaneously increase the viscosity in water solution and reduce the interfacial tension (IFT) in the water/oil system, which would increase the efficiency of EOR processes. This article shows a methodological evaluation through laboratory studies, numerical reservoir simulation, and conceptual engineering design to apply polymeric surfactants (Block Copolymer Polymeric Surfactants or BCPS) as additives to improve efficiency in water injection processes. Block copolymer type products of ethylene oxide (EO) - propylene oxide (PO) - ethylene oxide (EO) in aqueous solution were studied to determine their rheological and surfactant behavior under the operating conditions of a Colombian field. In the conditions studied, these products allow to reduce the interfacial tension up to 2x10-1 mN/m values and also cause a shear-thinning rheological behavior following the power law at very low shear rates (0.1 s-1– 1 s-1), which corresponds to an increase up to four orders of magnitude in the capillary number (Nc). The IFT and the viscosity reached are maintained in wide ranges of salinity, BCPS concentration, and shear rates, making it a robust performance formulation. In a model porous medium, BCPS tested have moderate adsorption, less than conventional surfactants but higher than HPAM polymers, in a, Formulaciones químicas incluyendo surfactantes, polímeros, álcalis o combinaciones de los mismos, han sido ampliamente usadas en diferentes procesos de recobro mejorado de petróleo para hacer más eficientes los procesos de inyección de agua. Sin embargo, en función de los retos del bajo margen de rentabilidad de la mayoría de proyectos maduros de inyección de agua en Colombia y en el mundo, se hace necesario explorar alternativas que ofrezcan mejor desempeño y mayor flexibilidad operativa que las tecnologías convencionales para procesos de recobro. Los surfactantes poliméricos son compuestos ampliamente usados para la elaboración de productos domésticos e industriales de limpieza, farmacéuticos, cosméticos y alimentos. Estos compuestos representan una interesante alternativa, ya que pueden proveer simultáneamente un incremento en la viscosidad del agua y causar una reducción de la tensión interfacial en sistemas agua/aceite, lo cual aumentaría la eficiencia de los procesos de recobro mejorado de petróleo. Este artículo describe una evaluación metodológica a través de estudios de laboratorio, simulación numérica de yacimiento e ingeniería conceptual de la aplicación de surfactantes poliméricos como aditivos para mejorar la eficiencia en procesos de inyección de agua. Productos de tipo copolímero en bloques óxido de etileno (EO) – óxido de propileno (PO) – óxido de etileno (EO) en solución acuosa (BCPS) fueron estudiados para determinar su comportamiento reológico y poder tensioactivo en condiciones de aplicación de yacimiento Colombiano. Bajo las condiciones evaluadas estos productos permiten reducir la tensión interfacial (IFT) hasta el orden de 2x10-1mN/m con un comportamiento reológico pseudoplástico que sigue la ley de potencia en esfuerzos de corte muy bajos (0,1 s-1 – 1 s-1), lo cual corresponde con un aumento de hasta tres órdenes de magnitud en el número capilar. La tensión interfacial y la viscosidad alcanzada se mantienen en amplios rangos de salinidad, con

Chemical formulations, including surfactants, polymers, alkalis, or their combinations, are widely used in different oil recovery processes to improve water injection performance. However, based on challenging profit margins in most mature waterfloods in Colombia and overseas, it is necessary to explore alternatives that could offer better performance and greater operational flexibility than the conventional technologies used for enhanced oil recovery (EOR) processes. Polymeric surfactants are compounds widely used in the manufacture of domestic and industrial cleaning, pharmaceutical, cosmetic, and food products. These compounds represent an interesting alternative as they can simultaneously increase the viscosity in water solution and reduce the interfacial tension (IFT) in the water/oil system, which would increase the efficiency of EOR processes. This article shows a methodological evaluation through laboratory studies, numerical reservoir simulation, and conceptual engineering design to apply polymeric surfactants (Block Copolymer Polymeric Surfactants or BCPS) as additives to improve efficiency in water injection processes. Block copolymer type products of ethylene oxide (EO) - propylene oxide (PO) - ethylene oxide (EO) in aqueous solution were studied to determine their rheological and surfactant behavior under the operating conditions of a Colombian field. In the conditions studied, these products allow to reduce the interfacial tension up to 2x10-1 mN/m values and also cause a shear-thinning rheological behavior following the power law at very low shear rates (0.1 s-1– 1 s-1), which corresponds to an increase up to four orders of magnitude in the capillary number (Nc). The IFT and the viscosity reached are maintained in wide ranges of salinity, BCPS concentration, and shear rates, making it a robust performance formulation. In a model porous medium, BCPS tested have moderate adsorption, less than conventional surfactants but higher than HPAM polymers, in a, Formulaciones químicas incluyendo surfactantes, polímeros, álcalis o combinaciones de los mismos, han sido ampliamente usadas en diferentes procesos de recobro mejorado de petróleo para hacer más eficientes los procesos de inyección de agua. Sin embargo, en función de los retos del bajo margen de rentabilidad de la mayoría de proyectos maduros de inyección de agua en Colombia y en el mundo, se hace necesario explorar alternativas que ofrezcan mejor desempeño y mayor flexibilidad operativa que las tecnologías convencionales para procesos de recobro. Los surfactantes poliméricos son compuestos ampliamente usados para la elaboración de productos domésticos e industriales de limpieza, farmacéuticos, cosméticos y alimentos. Estos compuestos representan una interesante alternativa, ya que pueden proveer simultáneamente un incremento en la viscosidad del agua y causar una reducción de la tensión interfacial en sistemas agua/aceite, lo cual aumentaría la eficiencia de los procesos de recobro mejorado de petróleo. Este artículo describe una evaluación metodológica a través de estudios de laboratorio, simulación numérica de yacimiento e ingeniería conceptual de la aplicación de surfactantes poliméricos como aditivos para mejorar la eficiencia en procesos de inyección de agua. Productos de tipo copolímero en bloques óxido de etileno (EO) – óxido de propileno (PO) – óxido de etileno (EO) en solución acuosa (BCPS) fueron estudiados para determinar su comportamiento reológico y poder tensioactivo en condiciones de aplicación de yacimiento Colombiano. Bajo las condiciones evaluadas estos productos permiten reducir la tensión interfacial (IFT) hasta el orden de 2x10-1mN/m con un comportamiento reológico pseudoplástico que sigue la ley de potencia en esfuerzos de corte muy bajos (0,1 s-1 – 1 s-1), lo cual corresponde con un aumento de hasta tres órdenes de magnitud en el número capilar. La tensión interfacial y la viscosidad alcanzada se mantienen en amplios rangos de salinidad, con

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.

Atherosclerosis, a leading cause of mortality in developed countries, is characterized by the buildup of oxidized low-density lipoprotein (oxLDL) within the vascular intima, unregulated oxLDL uptake by macrophages, and ensuing formation of arterial plaque. Amphiphilic polymers (AMPs) comprised of a branched hydrophobic domain and a hydrophilic poly(ethylene glycol) (PEG) tail have shown promising anti-atherogenic effects through direct inhibition of oxLDL uptake by macrophages. In this study, five AMPs with controlled variations were evaluated for their micellar and structural stability in the presence of serum and lipase, respectively, to develop underlying structure-atheroprotective activity relations. In parallel, molecular dynamics simulations were performed to explore the AMP conformational preferences within an aqueous environment. Notably, AMPs with ether linkages between the hydrophobic arms and sugar backbones demonstrated enhanced degradation stability and storage stability, and also elicited enhanced anti-atherogenic bioactivity. Additionally, AMPs with increased hydrophobicity elicited increased atheroprotective bioactivity in the presence of serum. These studies provide key insights for designing more serum-stable polymeric micelles as prospective cardiovascular nanotherapies.

Self-assembled nanoparticles have reached a growing interest for the improvement ofcancer diseases and associated inflammation processes. This article describes the mostrepresentative types of self-assembling nanosystems, including a detailed review ofdifferent methodologies for their preparation. Nanoparticles are commonly formed by self-assembling of amphiphilic polymers in aqueous environment. For that reason, the mainstrategies for the design of amphiphilic polymeric systems are also reviewed, with anemphasis on the different polymerization techniques of synthetic monomers and severalstrategies of chemical modification of polysaccharides and proteins. Additionally, mostadvanced applications of self-assembled nanocarriers for the improvement of treatmentof cancer and inflammation diseases are also discussed, focusing on the description ofdrug-loaded and drug-conjugated systems, active targeted strategies and most recentlypossibilities for the multimodality treatment of cancer diseases.

Stimulus-induced changes in surface properties of nanoassemblies have been of interest in a variety of applications. One such change involves change in surface charge. Changes in surface charge can be conveniently assayed using interaction of the nanoassemblies with cells. We have utilized the nanoassembly-cell interaction to investigate the pH-induced changes in surface properties. Similarly, surface functionalization of nanoparticles and host-guest properties of nanoassemblies are two critical features in the utilization of nanostructures in a variety of applications in materials, chemical, and biological nanotechnology. However, simultaneously incorporating these two features in one nanoparticle design is a rather challenging task. We were interested in developing a simple approach for functionalizable polymer nanoparticles, where we stipulated that: (i) the precursor polymer is based on a random copolymer, which is synthetically accessible; (ii) the polymer self-assembles in a solvent, which can then be converted to nanoparticle in one step without the need for any additional processing; (iii) the nanoparticle contains a surface functional group, which can be further manipulated easily; (iv) the size of the nanoparticle is tunable; and (iv) the interior of the nanoparticle is capable of sequestering guest molecules., The original document contains color images.

This review initially summarizes the mechanisms, merits and limitations of the three controlled radical polymerizations: nitroxide mediated polymerization (NMP), atom transfer radical polymerization (ATRP) or metal catalyzed living radical polymerization, and reversible addition–fragmentation chain transfer (RAFT) polymerization. This is followed by two parts, one dealing with homo- and copolymerizations of fluorinated methacrylates and acrylates, and a second where fluorinated styrenes, alone or in combination with other monomers, are the main issues. In these parts, initiators (including multifunctional and macroinitiators), ligands and other reaction conditions as well as some kinetics and conversions are discussed. Numerous possibilities for preparation of a variety of different block copolymers where one or more blocks are fluorinated are devoted particular attention. The advantageous properties and functionalities that can be obtained from these novel fluorinated materials and architectures are especially emphasized. Thus, various amphiphilic, biocompatible or low energy materials, fluorinated nanoparticles and nanoporous films/membranes as well as materials for submicron and nanolevel electronics have been fabricated. In addition, the possible fluorination of various surfaces through surface initiation is highlighted. A final part deals with the use of fluorine containing initiators and macroinitiators, and the applications on the novel materials derived thereof.

This review initially summarizes the mechanisms, merits and limitations of the three controlled radical polymerizations: nitroxide mediated polymerization (NMP), atom transfer radical polymerization (ATRP) or metal catalyzed living radical polymerization, and reversible addition–fragmentation chain transfer (RAFT) polymerization. This is followed by two parts, one dealing with homo- and copolymerizations of fluorinated methacrylates and acrylates, and a second where fluorinated styrenes, alone or in combination with other monomers, are the main issues. In these parts, initiators (including multifunctional and macroinitiators), ligands and other reaction conditions as well as some kinetics and conversions are discussed. Numerous possibilities for preparation of a variety of different block copolymers where one or more blocks are fluorinated are devoted particular attention. The advantageous properties and functionalities that can be obtained from these novel fluorinated materials and architectures are especially emphasized. Thus, various amphiphilic, biocompatible or low energy materials, fluorinated nanoparticles and nanoporous films/membranes as well as materials for submicron and nanolevel electronics have been fabricated. In addition, the possible fluorination of various surfaces through surface initiation is highlighted. A final part deals with the use of fluorine containing initiators and macroinitiators, and the applications on the novel materials derived thereof.

Amphiphilic polymers are a class of polymers that self-assemble into different types of microstructure, depending on the solvent environment and external stimuli. Self assembly structures can exist in many different forms, such as spherical micelles, rod-like micelles, bi-layers, vesicles, bi-continuous structure etc. Most biological systems are basically comprised of many of these organised structures arranged in an intelligent manner, which impart functions and life to the system. We have adopted the atom transfer radical polymerization (ATRP) technique to synthesize various types of block copolymer systems that self-assemble into different microstructure when subject to an external stimuli, such as pH or temperature. The systems that we have studied are: (1) pH responsive fullerene (C60) containing poly(methacrylic acid) (PMAA-b-C60); (2) pH and temperature responsive fullerene containing poly[2-(dimethylamino)ethyl methacrylate] (C₆₀-b-PDMAEMA); (3) other responsive water-soluble fullerene systems. By varying temperature, pH and salt concentration, different types microstructure can be produced. In the presence of inorganic salts, fractal patterns at nano- to microscopic dimension were observed for negatively charged PMAA-b-C60, while such structure was not observed for positively charged PDMAEMA-b-C60. We demonstrated that negatively charged fullerene containing polymeric systems can serve as excellent nano-templates for the controlled growth of inorganic crystals at the nano- to micrometer length scale and the possible mechanism was proposed. The physical properties and the characteristics of their self-assembly properties will be discussed, and their implications to chemical and biomedical applications will be highlighted., Singapore-MIT Alliance (SMA)

Structural proteinomics is providing rapid insight into the structural and biological functions of many proteins. Our intention was to use this understanding to develop polymers that are more stable and inexpensive to produce than natural proteins, but nevertheless mimic their important biological properties. Toward this goal, we have focused on the host defense peptides, which are a broad class of peptides with remarkable antimicrobial properties against a host of organisms including Gram- negative and Gram-positive bacteria. These peptides have a common physiochemical motif that leads to their biological activity, which is an overall cationic and amphiphilic architecture. We developed polymers that also have an overall cationic and amphiphilic architecture similar to the peptides. Recently, similar work has been reported on beta-amino acids however these materials are still very labor intensive and expensive to produce. Nonetheless, they demonstrate that non-natural polymers can be used to mimic peptide activity. We developed a family of very inexpensive polymers that mimic the structural characteristics of amphiphilic beta-sheet peptides.

This report on the Conference on Assembly and Self-Assembly at the Interface of Biology, Chemistry, and Physics held in Il Ciocco, Italy, on August 20-25, 2001, includes an overview, the program, attendee list, and presentation abstracts. Recent advances, such as scanning probe microscopy, genetic approaches in molecular biology, optical traps, and single molecule microscopy and spectroscopy, created a natural interface between the worlds of chemistry, physics, and biology by exploring the nanometer scale. This is the fundamental length scale where novel mesoscopic materials confront the building blocks of life: proteins and DNA. These developments in nanoscience, together with visions of nanoengineering and lessons from cell and molecular biology define a current challenge: manufacturing complex, heterogeneous structures of well-controlled architecture and function. The attainment of this objective requires a deeper knowledge of assembly and self-assembly (ASA) as encountered in biology, chemistry, and physics. More specifically, the design of fundamentally new materials depends on an understanding of how the desired structural theme or complex function is "coded" into the molecular architecture of the reactants. The study of ASA is essential to all three disciplines. However, the design parameters, the control strategies, and the nature of the end products differ widely in these fields. The ASA interdisciplinary conference seeks to promote the exchange of ideas between different and weakly interacting communities, namely physics and chemistry of soft matter, supramolecular chemistry, and cell and molecular biology. Furthermore, it attempted to enhance contacts between industrial and academic research laboratories., Support for this conference also was provided by the European Union, the U.S. Office of Naval Research (ONR), the European Office of Aerospace Research & Development (EOARD), the Defense Advanced Research Projects Agency (DARPA), SPrAM, the Mainz Academy of Science, Evacyte, BASF, Hoffman-La Roche, DSM, Merck, Bayer, Shlumberger, and the CEA.

Polyacetylene is a symmetric chain of conjugated macromolecule, whose chain symmetry can, however, be broken by external and internal perturbations, generating spirally rotating molecular wires. The external approach involves the use of asymmetric force field and interactive complexing agents, while the internal one involves the covalent attachment of stereogenic pendants to the conjugated backbone at the molecular level. Incorporation of naturally occurring building blocks such as amino acids, saccharides, and nucleobases into polyacetylene structure results in the formation of optically active polymers, whose chain helicity can be continuously and reversibly tuned by simple external stimuli such as solvent and pH. The amphiphilic polyacetylenes, in response to the changes in their environments, self-associate into robust organizational morphologies reminiscent of natural hierarchical structures such as helix, vesicle, honeycomb pattern, and mollusk shape. © 2001 OPA (Overseas Publishers Association) Amsterdam B.V. Published under licence by Gordon and Breach Science Publishers SA.

Polyacetylene is a symmetric chain of conjugated macromolecule, whose chain symmetry can, however, be broken by external and internal perturbations, generating spirally rotating molecular wires. The external approach involves the use of asymmetric force field and interactive complexing agents, while the internal one involves the covalent attachment of stereogenic pendants to the conjugated backbone at the molecular level. Incorporation of naturally occurring building blocks such as amino acids, saccharides, and nucleobases into polyacetylene structure results in the formation of optically active polymers, whose chain helicity can be continuously and reversibly tuned by simple external stimuli such as solvent and pH. The amphiphilic polyacetylenes, in response to the changes in their environments, self-associate into robust organizational morphologies reminiscent of natural hierarchical structures such as helix, vesicle, honeycomb pattern, and mollusk shape. © 2001 OPA (Overseas Publishers Association) Amsterdam B.V. Published under licence by Gordon and Breach Science Publishers SA.

Polyacetylene is a symmetric chain of conjugated macromolecule, whose chain symmetry can, however, be broken by external and internal perturbations, generating spirally rotating molecular wires. The external approach involves the use of asymmetric force field and interactive complexing agents, while the internal one involves the covalent attachment of stereogenic pendants to the conjugated backbone at the molecular level. Incorporation of naturally occurring building blocks such as amino acids, saccharides, and nucleobases into polyacetylene structure results in the formation of optically active polymers, whose chain helicity can be continuously and reversibly tuned by simple external stimuli such as solvent and pH. The amphiphilic polyacetylenes, in response to the changes in their environments, self-associate into robust organizational morphologies reminiscent of natural hierarchical structures such as helix, vesicle, honeycomb pattern, and mollusk shape. © 2001 OPA (Overseas Publishers Association) Amsterdam B.V. Published under licence by Gordon and Breach Science Publishers SA.

A series of amphiphilic copolymers is prepared by copolymerization of choline methacrylate with 1,1,2,2-tetrahydroperfluorooctyl methacrylate in varying amounts. The copolymers bearing fluorocarbon chains are studied concerning their effects on viscosity, solubilization and surface activity in aqueous solution, exhibiting a general behavior characteristic for polysoaps. The results are compared with the ones obtained for an analogous series of amphiphilic copolymers bearing hydrocarbon chains.

Sound velocity measurements were made to obtain compressibility values at 2 MHz, and to investigate the influence of the interface in dispersions of electrostatically stablized dispersions. The measurements were on aqueous dispersions of polystyrene latex as a function of volume concentration up to 49% and temperature up to 80 C (approaching the glass transition temperature), and in solutions of 72.5%, and 78% hydrolyzed polyvinyl alcohol-polyvinyl acetate block copolymers (PVA) as a function of temperature above and below their cloud points. The measurements were extended to latex coated with PVA under conditions known to give a 30 nm layer at room temperature. These dispersions give a resultant compressibility lower than expected from the simple additive effect of the separate components at 25 C and higher. The decrease in compressibility may be due to either or both of two effects: the hydrophobic interaction between the acetate groups and the polymer backbone of the polystyrene latex results in a more rigid structure, and the suppression by the PVA coating of the association-dissociation reaction responsible for the remarkable high adsorption of ultrasound will result in a lower compressibility. (Author)

The cationic peptide, salmon calcitonin (sCT) was complexed with the cationic amphiphilic polyelectrolyte, poly(allyl)amine, grafted with palmitoyl and quaternary ammonium moieties at pH 5.0 and 7.4 to yield particulates (sCT-QPa). The complexes were approximately 200 nm in diameter, had zeta potentials ranging from + 20 to + 50 mV, and had narrow polydispersity indices (PDIs). Differential scanning calorimetry revealed the presence of an interaction between sCT and QPa in the complexes. Electron microscopy confirmed the zeta-size data and revealed a vesicular bilayer structure with an aqueous core. Tyrosine-and Nile red fluorescence indicated that the complexes retained gross physical stability for up to 7 days, but that the pH 5.0 complexes were more stable. The complexes were more resistant to peptidases, serum and liver homogenates compared to free sCT. In vitro bioactivity was measured by cAMP production in T47D cells and the complexes had EC50 values in the nM range. While free sCT was unable to generate cAMP following storage for 7 days, the complexes retained approximately 33% activity. When the complexes were injected intravenously to rats, free and complexed sCT (pH 5.0 and 7.4) but not QPa reduced serum calcium over 120 min. Free and complexed sCT but not QPa also reduced serum calcium over 240 min following intra-jejunal administration. In conclusion, sCT-QPa nanocomplexes that have been synthesised are stable, bioactive and resistant to a range of peptidases. These enhanced features suggest that they may have the potential for improved efficacy when formulated for injected and oral delivery.

© 2015 Elsevier B.V. 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.

Pluronic block copolymers L61 and L121 were reacted with succinic anhydride to produce, respectively, their mono- and bisderivatives with succinic acid. The critical micelle concentration of Pluronics decreased after modification. The modification of Pluronic L61 promoted its association with the plasma membrane of human cells and increased membrane damage, while the membranotropic activity of modified Pluronic L121 reduced compared to the initial copolymer. Modified Pluronics interfered with the viability, apoptosis induction and metabolism of A549 cells and skin fibroblasts to a much lesser extent presumably due to the introduction of succinic acid residue inhibited intracellular penetration of copolymers. Modified Pluronic L121 promoted the cellular uptake of doxorubicin and rhodamine 123 in A549 cells attributed to the inhibition of membrane P-glycoprotein. Our study provides an approach to assessing the mechanism of interaction of amphiphilic polymers with living cells and demonstrates that Pluronic-succinic acid conjugates can be used as safe and efficient modulators of intracellular drug delivery. © 2013 Elsevier B.V.

Pluronic block copolymers L61 and L121 were reacted with succinic anhydride to produce, respectively, their mono- and bisderivatives with succinic acid. The critical micelle concentration of Pluronics decreased after modification. The modification of Pluronic L61 promoted its association with the plasma membrane of human cells and increased membrane damage, while the membranotropic activity of modified Pluronic L121 reduced compared to the initial copolymer. Modified Pluronics interfered with the viability, apoptosis induction and metabolism of A549 cells and skin fibroblasts to a much lesser extent presumably due to the introduction of succinic acid residue inhibited intracellular penetration of copolymers. Modified Pluronic L121 promoted the cellular uptake of doxorubicin and rhodamine 123 in A549 cells attributed to the inhibition of membrane P-glycoprotein. Our study provides an approach to assessing the mechanism of interaction of amphiphilic polymers with living cells and demonstrates that Pluronic-succinic acid conjugates can be used as safe and efficient modulators of intracellular drug delivery. © 2013 Elsevier B.V.

© 2015 Elsevier B.V. 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.

The cationic peptide, salmon calcitonin (sCT) was complexed with the cationic amphiphilic polyelectrolyte, poly(allyl)amine, grafted with palmitoyl and quaternary ammonium moieties at pH 5.0 and 7.4 to yield particulates (sCT-QPa). The complexes were approximately 200 nm in diameter, had zeta potentials ranging from + 20 to + 50 mV, and had narrow polydispersity indices (PDIs). Differential scanning calorimetry revealed the presence of an interaction between sCT and QPa in the complexes. Electron microscopy confirmed the zeta-size data and revealed a vesicular bilayer structure with an aqueous core. Tyrosine-and Nile red fluorescence indicated that the complexes retained gross physical stability for up to 7 days, but that the pH 5.0 complexes were more stable. The complexes were more resistant to peptidases, serum and liver homogenates compared to free sCT. In vitro bioactivity was measured by cAMP production in T47D cells and the complexes had EC50 values in the nM range. While free sCT was unable to generate cAMP following storage for 7 days, the complexes retained approximately 33% activity. When the complexes were injected intravenously to rats, free and complexed sCT (pH 5.0 and 7.4) but not QPa reduced serum calcium over 120 min. Free and complexed sCT but not QPa also reduced serum calcium over 240 min following intra-jejunal administration. In conclusion, sCT-QPa nanocomplexes that have been synthesised are stable, bioactive and resistant to a range of peptidases. These enhanced features suggest that they may have the potential for improved efficacy when formulated for injected and oral delivery.