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Macroporous polymer monoliths prepared from high internal phase emulsions (HIPEs) can be found in various biomedical applications. While typically water-in-oil HIPEs are applied for polyHIPE preparation, they are not suitable for hydrophilic polyHIPE preparation. Herein, direct oil-in-water emulsions based on water-soluble poly(ethylene glycol)diacrylate or poly(ethylene glycol)dimethacrylate were developed. Furthermore, the incorporation of a hydrophilic water-miscible thiol, ethoxylated trimethylolpropane tris(3-mercaptopropionate) (ETTMP) was reported for the first time within thiol−ene polyHIPEs. Due to the transparency of the emulsions, rapid curing via photopolymerization was feasible. The average pore diameters of the resulting polyHIPEs ranged between 1.2 and 3.6 μm, and porosity of up to 90% was achieved. The water uptake of the materials reached up to 1000% by weight. Drug loading and release were demonstrated, employing salicylic acid as a model drug. Porous profile and biodegradability add to the usefulness of the material for biomedical applications.

For many decades, poly(2-oxazoline)s and poly(2-oxazine)s, two closely related families of polymers, have led the life of a rather obscure research topic with only a few research groups world-wide working with them. This has changed in the last five to ten years, presumably triggered significantly by very promising clinical trials of the first poly(2-oxazoline)-based drug conjugate. The huge chemical and structural toolbox poly(2-oxazoline)s and poly(2-oxazine)s has been extended very significantly in the last few years, but their potential still remains largely untapped. Here, specifically, the developments in macromolecular self-assemblies and non-covalent drug delivery systems such as polyplexes and drug nanoformulations based on poly(2-oxazoline)s and poly(2-oxazine)s are reviewed. This highly dynamic field benefits particularly from the extensive synthetic toolbox poly(2-oxazoline)s and poly(2-oxazine)s offer and also may have the largest potential for a further development. It is expected that the research dynamics will remain high in the next few years, particularly as more about the safety and therapeutic potential of poly(2-oxazoline)s and poly(2-oxazine)s is learned.

This research was aimed at the preparation of a hybrid film based on a layered silicate saponite (Sap) with the immobilized photosensitizer phloxine B (PhB). Sap was selected because of its high cation exchange capacity, ability to exfoliate into nanolayers, and to modify different surfaces. The X-ray diffraction of the films confirmed the intercalation of both the surfactant and PhB molecules in the Sap film. The photosensitizer retained its photoactivity in the hybrid films, as shown by fluorescence spectra measurements. The water contact angles and the measurement of surface free energy demonstrated the hydrophilic nature of the hybrid films. Antimicrobial effectiveness, assessed by the photodynamic inactivation on hybrid films, was tested against a standard strain and against methicillin-resistant bacteria of Staphylococcus aureus (MRSA). One group of samples was irradiated (green LED light, 2.5 h) and compared to nonirradiated ones. S. aureus strains manifested a reduction in growth from 1-log10 to over 3-log10 compared to the control samples with Sap only, and defects in S. aureus cells were proven by scanning electron microscopy. The results proved the optimal photo-physical properties and anti-MRSA potential of this newly designed hybrid system that reflects recent progress in the modification of surfaces for various medical applications.

Modification of thermogelling biodegradable copolymers with functional groups enables further covalent crosslinking of physical micelle-based hydrogels formed at specific temperature in water. The resulting hybrid hydrogel network exhibits an increase in stiffness and degradation stability. In this work, synthesized well-defined thermoresponsive alpha,omega-itaconyl-poly(d,l-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(d,l-lactide-co-glycolide) (alpha,omega-itaconyl-PLGA-PEG-PLGA) macromonomers with a high degree of itaconyl-substitution providing free double bonds are photocrosslinked in water at both 25 and 37 degrees C using lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LiTPO) acting as water-soluble non-toxic photoinitiator. The effect of LiTPO on the thixotropic behavior of macromonomer in water at 25 degrees C without irradiation is evaluated. With the addition of a low amount of the photoinitiator (0.1 wt%), the degree of copolymer thixotropy increases. However, further increase in the photoinitiator concentration (0.5-3 wt%) leads to a lower degree of thixotropy. The photoinitiator is presumably interfering with the micellar self-assembly of the copolymer. This trend is also reflected in photocrosslinking efficiency, where the hybrid hydrogel networks with the highest storage moduli are achieved with very low concentrations of the photoinitiator (0.1 wt%) at 25 degrees C, while this trend is reversed at 37 degrees C. The hydrolytic stability of hydrogels prepared at 37 degrees C from 17 wt% macromonomer solution with 1% LiTPO exceeds 22 days. Modifikace termosenzitivních biodegradabilních kopolymerů s funkčními skupinami umožňuje další kovalentní zesíťování fyzikálních hydrogelů na bázi micel vytvořených ve vodě při specifické teplotě. Výsledná hybridní hydrogelová síť vykazuje zvýšení tuhosti a degradační stability. V této práci byly syntetizováné dobře definované termoresponzivní , itaconylPLGAPEGPLGA) makromonomery s vysokým stupněm substituce kyseliny itakonové s volnými dvojnými vazbami, které byly fotosíťovány ve vodě při 25 i 37 ° C v přítonosti ve vodě rozpustného netoxického fotoiniciátoru lithium-fenyl 2,4,6-trimethylbenzoylfosfinátu (LiTPO).

The aim of this study was to use diffuse coplanar surface barrier discharge (DCSBD) non-thermal plasma for the disinfection of pine seed surfaces infected with Fusarium oxysporum spores. Artificially infected seeds of Scots pine (Pinus sylvestris L.) were treated with plasma for the following exposure times: 1 s, 3 s, 5 s, 10 s, 15 s, 20 s, 30 s, and 60 s, and subsequently germinated on agar medium in Petri dishes at room temperature for the estimation of seed germination and disinfection effect of plasma treatment. Results of the treated samples were compared to the control samples, which were prepared as follows: seeds uninfected and non-treated with plasma (first control), seeds infected with F. oxysporum and non-treated with plasma (second control), and seeds infected with F. oxysporum, non-treated with plasma, but sterilized with 30% perhydrol (third control). Obtained results indicate that 3 s plasma treatment was an optimal time to inhibit the F. oxysporum growth, and at the same time, increase the seed germination level. In addition, our results are the first to show the practical application of non-thermal plasma in disinfecting infected Scots pine seeds and improving their germination. According to the results of this study, non-thermal plasma can serve as a seed surface disinfectant in the regeneration system of different pine species.

Among external stimuli used to trigger release of a drug from a polymeric carrier, ultrasound has gained increasing attention due to its non-invasive nature, safety and low cost. Despite this attention, there is only limited knowledge about how materials available for the preparation of drug carriers respond to ultrasound. This study investigates the effect of ultrasound on the release of a hydrophobic drug, dexamethasone, from poly(2-oxazoline)-based micelles. Spontaneous and ultrasound-mediated release of dexamethasone from five types of micelles made of poly(2-oxazoline) block copolymers, composed of hydrophilic poly(2-methyl-2-oxazoline) and hydrophobic poly(2-n-propyl-2-oxazoline) or poly(2-butyl-2-oxazoline-co-2-(3-butenyl)-2-oxazoline), was studied. The release profiles were fitted by zero-order and Ritger-Peppas models. The ultrasound increased the amount of released dexamethasone by 6% to 105% depending on the type of copolymer, the amount of loaded dexamethasone, and the stimulation time point. This study investigates for the first time the interaction between different poly(2-oxazoline)-based micelle formulations and ultrasound waves, quantifying the efficacy of such stimulation in modulating dexamethasone release from these nanocarriers.

Minimizing the foreign body reaction to polyimide-based implanted devices plays a pivotal role in several biomedical applications. In this work, we propose materials exhibiting nonbiofouling properties and a Young's modulus reflecting that of soft human tissues. We describe the synthesis, characterization, and in vitro validation of poly(carboxybetaine) hydrogel coatings covalently attached to polyimide substrates via a photolabile 4-azidophenyl group, incorporated in poly(carboxybetaine) chains at two concentrations of 1.6 and 3.1 mol %. The presence of coatings was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy. White light interferometry was used to evaluate the coating continuity and thickness (between 3 and 6 mu m under dry conditions). Confocal laser scanning microscopy allowed us to quantify the thickness of the swollen hydrogel coatings that ranged between 13 and 32 mu m. The different hydrogel formulations resulted in stiffness values ranging from 2 to 19 kPa and led to different fibroblast and macrophage responses in vitro. Both cell types showed a minimum adhesion on the softest hydrogel type. In addition, both the overall macrophage activation and cytotoxicity were observed to be negligible for all of the tested material formulations. These results are a promising starting point toward future advanced implantable systems. In particular, such technology paves the way for novel neural interfaces able to minimize the fibrotic reaction, once implanted in vivo, and to maximize their long-term stability and functionality.

In this study, surface modification of carbonyl iron (CI) particles with sulfobetaine moieties (SBE) was performed by the silanization of activated CI to form stable CI-SBE particles. The modification led to a significant improvement of the thermo-oxidation stability and a negligible suppression of the magnetization of the particles, as revealed by thermogravimetric analysis and vibrating sample magnetometry, respectively. The effect of a magnetic field and temperature on the magnetorheological performance of particle suspensions was investigated using a rotational rheometer in order to clarify the suitability of these systems for the local embolization of blood veins. The suspension based on CI-SBE exhibited a pseudoplastic behaviour and a tunable yield stress in a range from 0.3-4 kPa at the normal human body temperature. Moreover, cell viability for fibroblasts and macrophages was examined via MTT assay, which revealed their suitability for the intended applications for the local embolization of blood veins. The Royal Society of Chemistry 2016. Scopus

Polylactic acid (PLA) is suitable for applications in packaging and biomedicine due to its biodegradability. To improve PLA surface adhesion a plasma-chemical treatment using nonthermal plasma generated in ambient air via diffuse coplanar surface barrier discharge (DCSBD) was used. The optimal treatment time and power were investigated. Interaction between active plasma species and the polymer surface, and the resulting surface changes were studied by contact angle measurement, surface energy determination, FTIR, and XPS. The most hydrophilic surface was obtained after only 3–4 s treatment. Treatment up to 10 s did not damage the polymer but longer treatments (30 and 60 s) caused partial degradation. The plasma broke C-C/C-H bonds and formed more C-O, O-C=O and C-O-C bonds. During storage surface oxygen decreased and a negligible amount of nitrogen was adsorbed. The oxygen-containing functional groups probably sank into the PLA volume after treatment.

The aim of the study is the comparison of inactivation efficiency of low-temperature plasma generated in different working gases for A. flavus inoculated on hazelnut surface. Plasma was generated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) in gases interesting in term of plasma properties – diffusiveness (nitrogen), oxidative potential (oxygen), role of OH radical formation (synthetic air with and without water vapour) and applicability (ambient air). The inactivation kinetics, explained by Weibull model, was strongly depended on used gas. Decimal reduction time (D-values) for tested fungi using oxygen, synthetic air with or without water vapour, ambient air and nitrogen plasma was 10 s, 32 s, 39 s, 41 s and 55 s, respectively. Reduction of A. flavus spore in oxygen and synthetic air with water vapour was from initial population of 4.6 CFU/g to below detection level (1.0 log10 CFU/g). Synthetic air without water vapour inactivated 2.56 log10 CFU/g, ambient air 2.95 log10 CFU/g and N2 1.69 log10 CFU/g after 180 s treatment. The characterization of plasma using optical emission spectrometry (OES) and Fourier Transform Infrared Spectroscopy (FTIR) was used for identification of active species in mentioned working gases participating in decontamination process – ozone, hydroxyl (OH) radicals, nitrogen oxides (NOx) and excited nitrogen species. A more complete characterization of the factors involved in inactivation by various plasmas will contribute to its better implementation in food quality.