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Metal complexes possess unique tunable properties, such as radioactivity, cytotoxicity or photophysical features, enabling them to act as diagnostic tracers or therapeutic agents. In applying them in biological systems, it is often necessary to enhance their solubility and biocompatibility. To achieve such goals, like the targeting of binding domains, transport systems and enzyme activities, the attachment of carbohydrate moieties appears to be suitable. Sugar-substitution in the periphery of metal complexes has therefore become a strongly growing field of research. Outlined herein is a selection of recent examples.

The overwhelming success of click chemistry encouraged researchers to develop alternative "spring-loaded" chemical reactions for use in different fields of chemistry. Initially, the copper(I)-catalyzed azide-alkyne cycloaddition was the only click reaction. In recent years, metal-free [3+2] cycloaddition reactions, Diels-Alder reactions, and thiol-alkene radical addition reactions have come to the fore as click reactions because of their simple synthetic procedures and high yields. Furthermore, these metal-free reactions have wide applicability and are physiologically compatible. These and other alternative click reactions expand the opportunities for synthesizing small organic compounds as well as tailor-made macromolecules and bioconjugates. This Minireview discusses the success and applicability of new, in particular metal-free, click reactions.

The local oxidation of self-assembled monolayers with a scanning probe is a promising method for the generation of structures with chemical functionalities on the nanometer scale. This technique, which takes advantage of the chemical stability and versatility of self-assembled monolayers and the ability to pattern these monolayers by scanning-probe-based oxidation methods, enables the hierarchical assembly of complex structures in a controlled manner. Surface modification can be followed by the assembly of a further functional monolayer and/or additional surface-modification reactions in the targeted, sequential construction of functional device features.

The cloud point of copolymers of 2-ethyl-2-oxazoline and 2-n-propyl-2-oxazoline could be tuned from 25 degrees C to 100 degrees C by varying molecular weight and composition; the reversibility and concentration dependence of the cloud points were evaluated to assess the potential of these copoly(2-oxazoline)s as alternatives to poly(N-isopropylacrylamide).

We report on the reversible and selective functionalization of surfaces by utilizing supramolecular building blocks. The reversible formation of terpyridine bis-complexes, based on a terpyridine ligand-functionalized monolayer, is used as a versatile supramolecular binding motif. Thereby, click chemistry was applied to covalently bind an acetylene functionalized Fe(II) bis-complex onto azide-terminated self-assembled monolayers. By decomplexation of the formed supramolecular complex, the ligand modified monolayer could be obtained. These monolayers were subsequently used for additional complexation reactions, resulting in the reversible functionalization of the substrates. The proper choice of the coordinating transition metal ions allows the tuning of the binding strength, as well as the physicochemical properties of the formed complexes and thus an engineering of the surface properties.

The use of nucleophilic displacement reactions on bromine-terminated monolayers is presented to create new functional moieties onto silicon surfaces. Functional amines were used as suitable nucleophiles to introduce versatile building blocks onto self-assembled monolayers to perform further surface chemistry toward the fabrication of surfaces with designed properties by combining compatible chemical routes. These modified substrates were analyzed by suitable surface sensitive techniques. Furthermore, the functional monolayers were used for different postmodification reactions. For example, functional amines facilitated with acetylene groups were applied in the click chemistry approach. The use of amino-functionalized terpyridine units leads to the construction of supramolecular systems, where the choice of the metal monocomplex for the complexation is important for the tuning of the surface properties.

This communication reports a versatile post-modification reaction of poly(pentafluorostyrene) building blocks in order to design multifunctional graft copolymers by taking advantage of the selective replacement of the para-fluorine groups.

Poly(2-nonyl-2-oxazoline-block-2-ethyl-2-oxazoline) block copolymer micelles were investigated as an alternative system to the approach proposed by He and Lodge (Y. He and T. P. Lodge, J. Am. Chem. Soc., 2006, 128, 12666) for the thermoreversible transfer of micelles between a hydrophobic ionic liquid phase and an aqueous phase; this work describes the possibility of thermally triggering and controlling this process.

The deposition behaviour of uniformly sized silica particles in drying aqueous droplets has been investigated for a range of particle sizes, 0.33, 1, 3 and 5 μm, in order to gain an improved understanding of the coffee drop effect. The droplets were produced by inkjet printing, which allowed multiple droplets of similar volume to be studied. Our observations show that particle size and the contact angle formed by the solvent droplet with the substrate determine how close to the boundary a particle is deposited. After drying, it was found that if the contact angle was less than 90°, smaller particles were located closer to the original droplet's periphery than larger particles in similar sized droplets. This deposition of particles can be explained by the wedge shape of the drying droplet's edge, which physically limits the movement of particles towards the droplet's periphery. In this paper we show that the size of a suspended particle influences the final dried morphology of a printed feature.

The living cationic ring-opening polymerization of 2-oxazolines with fluorinated aromatic substituents was found to be strongly accelerated by o-fluoro substituents.

Inkjet printing is an attractive patterning technology, which has become increasingly accepted for a variety of industrial and scientific applications. This review primarily presents an overview of the investigations that have been conducted since 2003 into inkjet-printing polymers or metal-containing inks and mentions related activities. The first section discusses the droplet-formation process in piezoelectric drop-on-demand printheads and the physical properties that affect droplet formation and the resolution of inkjet-printed features. The second section deals with the issues that arise from printing polymers, such as printability and the output characteristics of devices made by this route. Finally, the challenges and achievements attached to inkjet printing metal-containing inks are discussed before concluding with a few remarks about the future of the field.

The functionalization of surfaces and the ability to tailor their properties with desired physico-chemical functions is an important field of research with a broad spectrum of applications. These applications range from the modification of wetting properties, over the alteration of optical properties, to the fabrication of molecular electronic devices. In each of these fields, it is of specific importance to be able to control the quality of the layers with high precision. The present study demonstrates an approach that utilizes the 1,3-dipolar cycloaddition of terminal acetylenes to prepare triazole-terminated monolayers on different substrates. The characterization of the precursor monolayers, the optimization of the chemical surface reactions as well as the clicking of a fluorescent dye molecule on such azide-terminated monolayers was carried out. A coumarin 343 derivative was utilized to discuss the aspects of the functionalization approach. Based on this approach, a number of potential surface reactions, facilitated via the acetylene-substituted functional molecules, for a broad range of applications is at hand, thus leading to numerous possibilities where surface modifications are concerned. These modifications can be applied on non-structured surfaces of silicon or glass or can be used on structured surfaces. Various possibilities are discussed.

Poly(2-ethyl-2-oxazoline) (POZ) was synthesized by living cationic ring-opening polymerization under microwave irradiation yielding polymers with low polydispersity indices (PDI, 1.15). The polymerization was quenched with sodium carbonate yielding a hydroxyl end-group with a high degree of functionality. The hydroxyl group was converted to carboxylate and the polymer was purified by ionic exchange chromatography. Following activation to succinimidyl ester, POZ-conjugates to high and low molecular weight biomolecules, trypsin and Ara-C, were obtained. The properties of the conjugates were compared to those of the corresponding conjugates with poly(ethylene glycol) (PEG) of similar size. The coupling of POZ to trypsin did not affect the enzymatic activity towards low mass substrates but, on the contrary, reduced the activity on the higher mass ones. Furthermore, the POZ-protein conjugates showed hydrodynamic volumes and protein rejecting properties similar to those of PEG-conjugates. Similarly, the POZ-Ara-C conjugate revealed a drug release profile, stability towards the degrading enzyme cytidine deaminase and in vitro cytotoxicity comparable to what has already been described for the PEG derivative. These data support the potential of POZ as a versatile alternative to the well-known and widely used PEG for protein and drug conjugation and delivery.

Intrigued by natural responsive systems based on a combination of macromolecules and non-covalent interactions, polymer scientists have mimicked such systems by the formation of supramolecular polymers based on ionic interaction, hydrogen bonding and metal coordination. In recent years, the focus has shifted from rather simple non-directional and self-complementary interactions to the use of asymmetrical directional supramolecular interactions that allow the formation of complex responsive macromolecular architectures such as block copolymers, star-shaped polymers and graft copolymers. This feature article covers these recent developments on the use of asymmetrical supramolecular interactions in polymer science. Special attention is given to the formation of complex macromolecular architectures using directional supramolecular interactions. In addition, the responsiveness of the resulting macromolecular systems is discussed based on the assembly and/or disassembly that can be triggered by changes in external conditions.

We present a detailed systematic study of the synthesis and ability of fluorinated 2-phenyl-2-oxazolines to undergo polymerization. The synthesis of these compounds is based on a two-step procedure that gives the desired 2-oxazolines in moderate-to-good yields. All the compounds were fully characterized by IR and NMR ((1)H, (13)C, and (19)F) spectroscopy, mass spectrometry, and elemental analysis. The 2-oxazolines were subsequently used as monomers for living cationic ring-opening polymerization (CROP) with microwave irradiation as the heat source (T=140 degrees C), nitromethane as the solvent, and methyl tosylate as the initiator. The linear first-order kinetic plots of the polymerizations accompanied by a linear increase of the molecular weight with conversion and low polydispersity index (PDI) values (generally below 1.30) indicate a living polymerization mechanism. The resulting polymerization rates reflect a strong sensitivity to the quantity of fluorine substituents in general and the presence or absence of ortho-fluoro substituents of the phenyl ring in particular. All the polymers were isolated and characterized by size-exclusion chromatography and MALDI-TOF mass spectrometry. Finally, a detailed investigation of selected polymer properties was performed by using differential scanning calorimetry, thermogravimetric analysis, and contact-angle measurements, thus resulting in structure-property relationships. Whereas the thermal properties of the polymers are mostly influenced by the presence of ortho-fluoro substituents, the surface properties are mainly determined by the presence of para- and/or meta-fluoro substituents.

Polyoxazolines of various architectures and chemical functionalities can be prepared in a living and therefore controlled manner via cationic ring-opening polymerisation. They have found widespread applications, ranging from coatings to pigment dispersants. Furthermore, several polyoxazolines are water-soluble or amphiphilic and relatively non-toxic, which makes them interesting as biomaterials. This paper reviews the development of polyoxazoline-based polymers in biological and biomedical application contexts since the beginning of the millennium. This includes nanoscalar systems such as membranes and nanoparticles, drug and gene delivery applications, as well as stimuli-responsive systems.

The solubility of polymers can be significantly altered by the use of solvent mixtures. The solvent composition also effects the self-assembly properties of amphiphilic copolymers. In addition, water-ethanol mixtures are known to exhibit abnormal physicochemical properties due to the presence of hydration shells around the ethanol molecules, while at the same time both solvents have very low toxicity. However, the solution properties of amphiphilic copolymers in water-ethanol mixtures have been scarcely studied. Here we show that the solution polymer properties of amphiphilic copoly(2-oxazoline)s can be significantly altered in binary water-ethanol mixtures resulting in increased solubility, tuneable lower critical solution temperatures as well as polymer-solvent combinations with both a LCST followed by an UCST and improved dispersion stability. Surprisingly, it was found that polymers insoluble in both ethanol and water could be dissolved in water-ethanol mixtures, opening the way to novel formulations for drug delivery or personal care applications. Our results represent a straightforward method for tuning solution polymer properties without the synthetic efforts that are generally required to change the copolymer composition and properties.

A set of poly(isobornyl acrylate)--poly(1-ethoxyethyl acrylate) polymers has been prepared by atom transfer radical polymerization. The 1-ethoxyethyl protecting group can be removed by a mild thermal treatment yielding the poly(acrylic acid) segment. The thin film morphological behavior of selected block copolymers was studied for as well as deprotected block copolymers using atomic force microscopy (AFM). Low-temperature thermal treatment yielded strongly phase-separated cylindrical features whereas treatment at temperatures above the glass transition temperature of the individual polymer blocks resulted in the initial generation of a similar phase contrast followed by a decrease in phase contrast caused by selective surface enrichment of the more hydrophobic poly(isobornyl acrylate) segment.

The utilization of plant oil renewable resources as raw materials for monomers and polymers is discussed and reviewed. In an age of increasing oil prices, global warming and other environmental problems (e.g. waste) the change from fossil feedstock to renewable resources can considerably contribute to a sustainable development in the future. Especially plant derived fats and oils bear a large potential for the substitution of currently used petrochemicals, since monomers, fine chemicals and polymers can be derived from these resources in a straightforward fashion. The synthesis of monomers as well as polymers from plant fats and oils has already found some industrial application and recent developments in this field offer promising new opportunities, as is shown within this contribution. (138 references.)

Living/controlled polymerization techniques have enabled the synthesis of a large variety of different well-defined (co)polymer structures. In addition, the use of click chemistry in polymer science is a quickly emerging field of research since it allows the fast and simple creation of well-defined and complex polymeric structures in yields that were previously unattainable. In this critical review, the application of the azide-alkyne 1,3-dipolar cycloaddition for the construction of well-defined polymer architectures will be discussed in detail, providing a comprehensive overview for all disciplines related to polymeric materials.

A set of rigid, pi-conjugated linear mono- and bisterpyridines and star-shaped tristerpyridines have been synthesized using Pd(0)-catalyzed coupling reactions and the Horner-Wadsworth-Emmons reaction. The terpyridyl ligands obtained feature strong emission in the blue range with high quantum yields in dilute solution and thin films.

1-Alkyl-3-methylimidazolium-based ionic liquids, having chloride as a counter ion, were studied for cellulose solubility; and the influence of different alkyl chain lengths was also investigated. The alkyl chain length was incrementally varied from ethyl to decyl to determine structure-dissolution properties; a distinct odd-even effect was observed for short chain lengths. In addition, the tritylation of cellulose was performed in 1-butyl-3-methylimidazolium chloride using pyridine as base. The influences of reaction time and the ratio of trityl chloride per cellulose monomer unit on the degree of substitution were investigated in detail by elemental analysis and 1H NMR spectroscopy. A DS of around 1 was obtained after 3 h reaction time using a six fold excess of trityl chloride.

The need for novel materials with luminescent properties and advanced processing features requires reliable and reproducible synthetic routes for the design of suitable materials, such as e.g. polypyridyl ruthenium(II) and iridium(III)-containing polymers. The most popular ligand for those purposes is the 4,4'-functionalized bipyridine unit. Therefore, several synthetic strategies for the derivatization of the 4,4'-dimethyl-2,2'-bipyridine are highlighted, and in particular functionalities, which enable further covalent linkage to polymeric structures, are discussed in this critical review. Subsequently, the different synthetic strategies for the preparation of polymeric metal-complexes are described, either starting from small functionalized complexes (later covalently attached to the polymer), or from macroligands (subsequently coordinated to the metal ions). The designed materials reveal good processing properties using spin coating and inkjet printing, as well as beneficial electro-optical properties for potential thin functional film applications, such as light-emitting electrochemical cells.

The interfacial properties of amphiphilic linear diblock copolymers based on poly(ethylene oxide) and poly(epsilon-caprolactone) (PEO-b-PCL) were studied at the air-water (A/W) interface by surface pressure measurements (isotherms and hysteresis experiments). The resulting Langmuir monolayers were transferred onto mica substrates and the Langmuir-Blodgett (LB) film morphologies were investigated by atomic force microscopy (AFM). All block copolymers had the same PEO segment (Mn = 2670 g/mol) and different PCL chain lengths (Mn = 1270; 2110; 3110 and 4010 g/mol). Isothermal characterization of the block copolymer samples indicated the presence of three distinct phase transitions around 6.5, 10.5, and 13.5 mN/m. The phase transitions at 6.5 and 13.5 mN/m correspond to the dissolution of the PEO segments in the water subphase and crystallization of the PCL blocks above the interface similarly as for the corresponding homopolymers, respectively. The phase transition at 10.5 mN/m was not observed for the homopolymers alone or for their blends and arises from a brush formation of the PEO segments anchored underneath the adsorbed hydrophobic PCL segments. AFM analysis confirmed the presence of PCL crystals in the LB films with unusual hairlike/needlelike architectures significantly different from those obtained for PCL homopolymers.

A statistical approach is described to better understand the role of the matrix during a MALDI-TOFMS experiment. Potential matrix molecules were selected based on a rational experimental design and subsequently screened in order to investigate whether a certain compound can act as a matrix for synthetic polymers. The tested compounds were selected from a pool of 11 000 molecules based on descriptor calculations and a subsequent D-optimal design selection procedure. This approach selected 59 organic compounds that were then investigated for their ability to act a matrix for synthetic polymers in MALDI-TOFMS experiments. Within this contribution, we focus on the discussion of new MALDI-TOFMS matrixes that were discovered in the course of the screening. At least 10 new matrices were identified, and 5 of these were subsequently tested more closely with a variety of different synthetic polymers of different molecular weights revealing good to excellent performance of these new matrices.

An aqueous 40 wt% dispersion of polyurethane has been successfully printed at room temperature using a piezoelectric inkjet printer. Simple layered structures, as well as dots, were made and subsequently analyzed using white-light interferometry. A single layer was found to have a structure height of 10 µm; a value that suggests that this polyurethane dispersion may be suitable for use in rapid prototyping, since tall structures can be rapidly produced using only a few printing passes. Finally, by the simple addition of a water-soluble dye, colour gradients were produced using this printing technique.

The formation of micelles on surfaces by spin-coating dilute solutions of diblock, triblock, and tetrablock copoly(2-oxazoline)s in a non-selective solvent is demonstrated. The micelles are not preexistent in the initial solution but are formed during the evaporation of the solvent by precipitation of the least-soluble block. The morphology and size of the micelles vary according to the fraction of this block but are not dependent on the block order in the copolymer.

Aqueous solutions of ionic liquids have been used as novel and environmentally friendly reaction media to synthesize and "control" the size of different cross-linked polymer beads by suspension polymerization reactions. It was found that the investigated ionic liquids can act as novel stabilizing agents of the suspensions as a result of their surface-active properties. The results have demonstrated that the average size of polymer beads can be varied from the macro- to the nanoscale and their surface area can also be "adjusted" by this synthetic approach. Furthermore, the use of a combination of ionic liquids and water for the synthesis of polymers, the simple isolation of the products formed in this polymerization procedure, as well as the recycling of the continuous medium for further reactions open up possibilities for the development of "new and green" polymerization processes.

Self-assembly of poly(ethylene oxide)-block-poly(epsilon-caprolactone) five-arm stars (PEO-b-PCL) was studied at the air/water (A/W) interface. The block copolymers consist of a hydrophilic PEO core with hydrophobic PCL chains at the star periphery. All the polymers have the same number of ethylene oxide repeat units (9 per arm), and the number of epsilon-caprolactone repeat units ranges from 0 to 18 per arm. The Langmuir monolayers were analyzed by surface pressure/mean molecular area isotherms, compression-expansion hysteresis experiments, and isobaric relaxation measurements, and the Langmuir-Blodgett (LB) films' morphologies were investigated by atomic force microscopy (AFM). PCL homopolymers crystallize directly at the A/W interface in a narrow surface pressure range (11-15 mN/m). In the same pressure region, the star-shaped block copolymers undergo a phase transition corresponding to the collapse and the crystallization of the PCL chains as shown by the presence of a pseudoplateau in the isotherms. The LB films were prepared by transferring the Langmuir monolayers onto mica substrates at various surface pressures. AFM imaging confirmed the formation of PCL crystals in the LB monolayers of the PCL homopolymers and of the copolymers, but also showed that the PCL segments can undergo additional crystallization after monolayer transfer during water evaporation. The PCL crystal morphologies were also strongly influenced by the surface pressure and by the PEO segments.

The synthesis of star-shaped poly(epsilon-caprolactone) is described via azide-alkyne cycloaddition ('click' chemistry) and via self-assembly of polymeric ligands into [2 x 2] grid-like metal complexes ('supramolecular click' chemistry).

The living cationic ring opening polymerization of 2-ethyl-2-oxazoline performed in an ionic liquid under microwave irradiation showed an enhanced polymerization rate in comparison to the reaction in common organic solvents; the ionic liquid was efficiently recovered and reused in new reaction cycles, completely avoiding the use of organic volatile compounds.

We report on a simple procedure to tune the hydrophilicity of hybrid gold nanoparticles. The nanoparticles have been prepared in the core of a poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PEG-b-PCL) five-arm star block copolymer. A hydrophilic corona was then added to these hybrid gold nanoparticles by direct chemisorption of trithiocarbonate-containing poly(acrylic acid) chains. These polymers were synthesized by RAFT polymerization with a trithiocarbonate as the chain-transfer agent. The efficiency of the grafting was evidenced by TEM, AFM, and DLS and by the successful transfer of these nanoparticles from organic solvent to water.

The introduction of supramolecular interactions in synthetic polymers seems to be a promising approach towards novel 'smart' materials that combine both the (reversible) supramolecular interactions and the properties of the polymers. In this tutorial review, the use of (metallo-)supramolecular initiators for the preparation of end-functionalized (metallo-)supramolecular polymers will be discussed in detail. The different polymerization techniques that have been applied as well as the different ligands and metal complexes that were used to initiate these polymerizations will be discussed together with the resulting polymer properties.

3,6-Di(pyridin-2-yl)pyridazines are an interesting class of compounds because of their metal-coordinating ability resulting in the self-assembly into [2x2] gridlike metal complexes with copper(I) or silver(I) ions. These and other substituted pyridazines can be prepared by the inverse-electron-demand Diels-Alder reactions between acetylenes and 1,2,4,5-tetrazines. In this contribution, the effect of (superheated) microwave conditions on these generally slow cycloadditions is described. The cycloaddition of acetylenes to 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine could be accelerated from several days reflux in toluene or N,N-dimethylformamide to several hours in dichloromethane at 150 degrees C. In addition, the unexpected cycloaddition of the enol tautomers of various ketones and aldehydes to 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine is described in detail providing an alternative route for the synthesis of (substituted) pyridazines.

Analytical ultracentrifugation (AUC) is the leading technique for determining the molar mass, state of association in solution, and association constants of biological macromolecules. Even though it is little used for supramolecular polymers, this technique has already been shown to represent one of the best options in the characterization of these systems. The use of supramolecular assemblies in the field of nanotechnology requires the arrangement of such systems on surfaces, from solution. Therefore, the control and investigation of solution properties is of major importance. In this contribution we highlight the applicability and advantages of using AUC by presenting a summary of the results of the past few years on the characterization of various types of synthetic polymers and supramolecular polymer systems.

Combinatorial materials research (CMR) is still a relatively young field of research. Nevertheless, it already provides successful strategies for a fast and accurate evaluation of a large variety of different research problems. Some of these approaches in CMR considering polymeric materials will be discussed and highlighted within this contribution by focussing on three prominent literature examples: structure-property relationships in biomaterials research, material properties evaluation utilizing thin film polymer libraries as well as the parallel and automated study of polymer based reversed unimolecular micelles and their application possibilities. These examples are meant to demonstrate the almost unlimited possibilities of combinatorial approaches in polymer science rather than to provide an extended overview of the field.

A novel compound containing both a 2,2'-bipyridine as well as a 2-ureido-4[1H]-ureidopyrimidinone supramolecular moiety (3) has been synthesised and fully characterized by 1H-NMR, MALDI-TOFMS, UV-vis and IR spectroscopy. Subsequent coordination to iridium and ruthenium polypyridyl precursors allowed the formation of iridium(III) and ruthenium(II) polypyridyl dimers (5 and 7) assembled via quadruple hydrogen-bonding as well as metal coordination interactions. The syntheses and complete characterization of these materials by means of two-dimensional NMR techniques (1H-1H COSY and 1H-1H DOSY) as well as IR and MALDI-TOFMS are described in detail. Comparative studies of the optical properties of the luminescent model complexes (5' and '7) and the dimer species (5 and 7) are also illustrated. In addition, good processability of the materials has been demonstrated by inkjet printing leading to thin films revealing their potential for light-emitting devices.

Microwave-assisted polymerization has been utilized to synthesize amphiphilic poly(2-ethyl-2-oxazoline-block-2-"soy alkyl"-2-oxazoline) diblock copolymers (PEtOx-PSoyOx). The amphiphilic block copolymers have been used to prepare aqueous spherical micelles consisting of a PEtOx corona and a PSoyOx core, which have been further cross-linked by UV irradiation. The morphology of these cross-linked micelles has been shown to reversibly change from spheres to short rods referred to as rice grains whenever the micelles were transferred from water into acetone, a nonselective solvent for the constituent blocks. This morphological transition has been attributed to the swelling of the slightly cross-linked PSoyOx core.

A methodology for the rapid design, screening, and optimization of coating systems with surface relief structures, using a combination of statistical experimental design, high-throughput experimentation, data mining, and graphical and mathematical optimization routines was developed. The methodology was applied to photopolymers used in photoembossing applications. A library of 72 films was prepared by dispensing a given amount of sample onto a chemically patterned substrate consisting of hydrophilic areas separated by fluorinated hydrophobic barriers. Film composition and film processing conditions were determined using statistical experimental design. The surface topology of the films was characterized by automated AFM. Subsequently, models explaining the dependence of surface topologies on sample composition and processing parameters were developed and used for screening a virtual 4000-membered in silico library of photopolymer lacquers. Simple graphical optimization or Pareto algorithms were subsequently used to find an ensemble of formulations, which were optimal with respect to a predefined set of properties, such as aspect ratio and shape of the relief structures.

Methodologies for the rapid screening of coating systems were developed and applied to photopolymer lacquers for photoembossing applications. Continuous and discrete gradient libraries were prepared with a gradient in grating period along the short axis and along the long axis, a gradient in exposure energy, development temperature, film thickness, photoinitiator concentration, or monomer to polymer mass ratio. Discrete gradient libraries consisted of arrays of rectangular films made by pipetting a certain amount of sample onto a chemically patterned substrate consisting of hydrophilic patches surrounded by hydrophobic, fluorinated barriers. The shape and height of the photoembossed gratings were measured using an automated AFM. Optimum grating height was obtained for a 20-microm period at intermediate exposure energies, photoinitiator concentrations, or both. Height improves with development temperature (max 110 degrees C), monomer-to-polymer ratio (max 55 wt % monomer), and film thickness. Surface topography can also be optimized, depending on any specific application.

Polymers based on renewable resources are promising candidates for replacing common organic polymers, and thus, for reducing oil consumption. In this contribution we report the microwave-assisted synthesis of block and statistical copolymers from 2-ethyl-2-oxazoline and 2-"soy alkyl"-2-oxazoline via a cationic ring-opening polymerization mechanism. The synthesized copolymers were characterized by gel permeation chromatography and 1 H-NMR spectroscopy. The micellization of these amphiphilic copolymers was investigated by dynamic light scattering and atomic force microscopy to examine the effect of hydrophobic block length and monomer distribution on the resulting micellar characteristics.

The feasibility of sector spin coating (or combinatorial spin-coating) is demonstrated (i.e., spin coating of various samples onto one single substrate using a metal template to divide the substrate into sectors). Film thickness increases in an angular direction against the sense of rotation. In the radial direction, the film thickness is constant within 2%. A library of 8 poly(methyl methacrylate)/polystyrene-blends with varying composition was spin coated and subsequently analyzed using automated atomic force microscopy: 24 measurements could be performed within 72 min. The contact angles of a library of 16 polyoxazoline diblock copolymers were measured using one substrate with 16 spin-coated sectors. Forty-eight measurements could be performed within 50 min. On the basis of the surface energies calculated using the Owens-Wendt-Rath-Kaeble method, the library can be divided into three groups of polymers: those containing a dispersive nonyloxazoline block, those containing a polar phenyloxazoline block, and those containing neither.

The encapsulation behaviour and the resulting transition metal ion sensing capabilities of a 5-arm star-shaped polymer bearing terpyridine ligands on its periphery are described.

Nanoparticles prepared by self-assembly from oligonucleotides (ONs), protamine free base, and human serum albumin ("ternary proticles") are spheres of diameters around 200 nm. Substitution of the protamine free base by protamine sulfate leads to proticles of only around 40 nm in diameter with otherwise unchanged properties. The availability of drug delivery systems of very similar composition but grossly different size may be advantageous when dealing with cells which show size-dependent particle uptake. These nanoparticles are promising candidates for ON delivery to cells because of the following reasons: (1) They are stable for several hours in solutions of up to physiological ionic strength; (2) they are efficiently taken up by cells; (3) after cellular uptake, they easily release the ONs even when these are present as phosphorothioates.

Gold nanoparticles of improved stability against aggregation were prepared using poly(ethylene oxide)-block-poly(epsilon-caprolactone) (PEO-b-PCL) star-block copolymers. A five-arm star-shaped macroinitiator (PEO) was utilized for the automated parallel controlled ring-opening polymerization of epsilon-caprolactone to prepare a series of PEO-b-PCL star-block copolymers with a constant PEO core linked to PCL blocks of variable length. The PEO core was swelled with KAuCl4 in N,N-dimethylformamide (DMF), and gold nanoparticles were subsequently obtained by reduction with NaBH4. Since the process was always templated by the same PEO core for all investigated polymers, the average dimension of the formed gold nanoparticles was in the same range for all star-block copolymers. In sharp contrast, the size distribution and long-term stability against aggregation of the gold nanoparticles dispersed in DMF were strongly dependent on the PCL block length, confirming the role of PCL blocks as stabilizing blocks for these nanoparticles.