Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences

Bratek-Skicki A.

The rapidly-growing field of polymer stimuli-responsive materials (smart materials) resulted in many advances in designing and developing multi-functional systems, novel architectures, and new synthetic routes for many different applications. The smart polymer materials with a wide range of stimuli, such as pH, light, temperature, enzyme, redox, and electric and magnetic fields play an important role in many applications in many disciplines, including nanotechnology, biochemistry, medicine, materials science, polymer science, engineering, etc. This review aims to provide an introduction to stimuli-responsive polymeric materials, their preparation methods, and to discuss the design of various stimulus-responsive materials that are able to provide smart self-healing surfaces, sensors, actuators, and drug delivery systems in response to particular stimuli.

Piktel E., Suprewicz Ł., Depciuch J., Chmielewska S., Skłodowski K., Daniluk T., Król G., Kołat-Brodecka P., Bijak P., Pajor-Świerzy A., Fiedoruk K., Parlinska-Wojtan M., Bucki R.

Medical device-associated infections are a serious medical threat, particularly for patients with impaired mobility and/or advanced age. Despite a variety of antimicrobial coatings for medical devices being explored to date, only a limited number have been introduced for clinical use. Research into new bactericidal agents with the ability to eradicate pathogens, limit biofilm formation, and exhibit satisfactory biocompatibility, is therefore necessary and urgent. In this study, a series of varied-morphology gold nanoparticles in shapes of rods, peanuts, stars and spherical-like, porous ones with potent antibacterial activity were synthesized and thoroughly tested against spectrum of Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus clinical strains, as well as spectrum of uropathogenic Escherichia coli isolates. The optimization of gold nanoparticles synthesis allowed to develop nanomaterials, which are proved to be significantly more potent against tested microbes compared with the gold nanoformulations reported to date. Notably, their antimicrobial spectrum includes strains with different drug resistance mechanisms. Facile and cost-efficient synthesis of gold nanoparticles, remarkable bactericidal efficiency at nanogram doses, and low toxicity, underline their potential for development as a new coatings, as indicated by the example of urological catheters. The presented research fills a gap in microbial studies of non-spherical gold nanoparticles for the development of antimicrobial coatings targeting multidrug-resistant pathogens responsible for device-associated nosocomial infections.

Kharitonov D.S., Zimowska M., Ryl J., Zieliński A., Osipenko M.A., Adamiec J., Wrzesińska A., Claesson P.M., Kurilo I.I.

• Corrosion properties of WE43 Mg alloy in 0.05 M NaCl solution have been examined. • Na 2 MoO 4 inhibitor provides reliable inhibition in concentrations at and above 100 mM. • XPS and confocal Raman measurements revealed the chemical state of molybdenum compounds. • Inhibition effect is provided by a surface film of mixed Mo(V)–Mo(VI) species. • A two-step oxidation-reduction mechanism of corrosion inhibition has been proposed. Corrosion and corrosion inhibition of WE43 magnesium alloy were investigated in NaCl solutions containing different amounts of sodium molybdate. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. Electrochemical data showed that Na 2 MoO 4 inhibitor provides reliable inhibition at concentrations at and above 100 mM. Raman and XPS spectroscopy demonstrated that the formed surface layer consists of mixed Mo(V, IV) species. This layer provided inhibition with an efficiency of 91–99 % after 24 h of exposure. A two-step oxidation-reduction mechanism of corrosion inhibition of the WE43 alloy by aqueous molybdates was proposed.

Kharitonov D.S., Dobryden I., Sefer B., Ryl J., Wrzesińska A., Makarova I.V., Bobowska I., Kurilo I.I., Claesson P.M.

Corrosion properties of aluminum alloy AA6063-T5 were investigated in molybdate-containing NaCl solutions. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the m ...

Khivantsev K., Jaegers N.R., Kovarik L., Wang M., Hu J.Z., Wang Y., Derewinski M.A., Szanyi J.

• Uniform, micron-sized, low defect density SSZ-39 was prepared and loaded with Pd. • Pd/SSZ-39 exhibits high and stable PNA and CH 4 combustion performance. • Extremely high hydrothermal stability of Pd/SSZ-39 is observed. • No structural degradation of SSZ-39 framework even after 1000 °C treatment. • Above 815 °C hydrothermal aging results in the formation of large Pd particles. Uniform SSZ-39 (Si/Al ratio ∼12) crystals with an average size of about one micron were synthesized and used to support Pd (0.7–3 wt%) for PNA. The as-synthesized materials were characterized by FTIR, XRD, Helium Ion Microscopy, HAADF-STEM imaging, 27 Al, 29 Si, and 1 H- 29 Si CP solid state NMR spectroscopic techniques. FTIR studies with CO and NO probe molecules reveal that the majority of Pd is dispersed as isolated Pd(II) and Pd(II)−OH centers and as such is suitable as a low-temperature passive NOx adsorber. Pd(II)-NO, Pd(II)(OH)(NO), and Pd(II)(CO)(NO) complexes form in this material during PNA. Comparison to Pd/SSZ-13 (Si/Al ∼12) shows the superior hydrothermal stability of this new material, surviving hydrothermal aging up to 815 °C in 10 % H 2 O/Air for 16 h without a significant loss of activity. The SSZ-39 crystal structure remains intact during hydrothermal aging up to 1000 °C confirmed by XRD and HAADF-STEM imaging/EDS mapping. However, changes to the framework, as evidenced by high-field 27 Al NMR, during such severe hydrothermal treatment significantly alter the NOx release profiles. Besides PNA, this hydrothermally stable material (3 wt% Pd on SSZ-39; Si/Al ∼12) can be used as a robust methane combustion catalyst under practically relevant conditions (i.e., GHSV∼300 L/g*hr). This catalyst shows minimal deactivation after both hydrothermal aging at 750 and 800 °C and prolonged time on stream (105 h) at 425°C. In contrast, both 3 wt% Pd/alumina and 3 wt% Pd/SSZ-13 lose a significant portion of their activity under such conditions, marking an improvement over current technology.

Lenart-Boroń A., Prajsnar J., Guzik M., Boroń P., Chmiel M.

This study aimed to gain insight into the presence of antibiotics, occurrence of antimicrobial resistance and prevalence of extended-spectrum β-lactamase (ESBL) genes in Escherichia coli in surface water, based on the example of the Białka river, located in one of the most attractive tourist destinations in Poland. Water samples were collected in three sites: in the Tatra National Park (TNP), by the sewage discharge from the local treatment plant (STP) and c.a. 3 km downstream (DSTP). The analyses included determination of antibiotic content, enumeration of bacterial indicators of poor water quality, isolation and identification of Escherichia coli , which was subjected to antimicrobial susceptibility tests and assessment of ESBL-determining genes. Fourteen antimicrobials out of 24 tested were detected in river waters in varying concentrations. Trimethoprim and ofloxacin were most frequently detected. Most antibiotics were absent in the TNP, the highest numbers and the highest concentrations of antibiotics were observed by the STP discharge to decrease their content downstream. Culture-based tests of microbiological contamination showed similar results. Resistance to ampicillin was most frequent (64.5% strains), followed by cefazolin (50%). 20.6% of strains were ESBL-positive, while ESBL-determining gene, bla TEM was detected in 23.8% of E. coli strains. The largest percentage of antibiotic resistant and MDR E. coli strains was detected nearby the STP, indicating that malfunctioning STP may contribute largely to river water contamination downstream, also having significant environmental and economic impact. • Antibiotics, antimicrobial resistant E. coli and ESBL genes occur in pristine waters. • Malfunctioning STP can be source of antibiotic pollution and drug resistant bacteria. • Antibiotic load is reduced downstream of STPs but drug resistance is ubiquitous.

Gibała A., Żeliszewska P., Gosiewski T., Krawczyk A., Duraczyńska D., Szaleniec J., Szaleniec M., Oćwieja M.

The biocidal properties of silver nanoparticles (AgNPs) prepared with the use of biologically active compounds seem to be especially significant for biological and medical application. Therefore, the aim of this research was to determine and compare the antibacterial and fungicidal properties of fifteen types of AgNPs. The main hypothesis was that the biological activity of AgNPs characterized by comparable size distributions, shapes, and ion release profiles is dependent on the properties of stabilizing agent molecules adsorbed on their surfaces. Escherichia coli and Staphylococcus aureus were selected as models of two types of bacterial cells. Candida albicans was selected for the research as a representative type of eukaryotic microorganism. The conducted studies reveal that larger AgNPs can be more biocidal than smaller ones. It was found that positively charged arginine-stabilized AgNPs (ARGSBAgNPs) were the most biocidal among all studied nanoparticles. The strongest fungicidal properties were detected for negatively charged EGCGAgNPs obtained using (−)-epigallocatechin gallate (EGCG). It was concluded that, by applying a specific stabilizing agent, one can tune the selectivity of AgNP toxicity towards desired pathogens. It was established that E. coli was more sensitive to AgNP exposure than S. aureus regardless of AgNP size and surface properties.

Jamróz E., Khachatryan G., Kopel P., Juszczak L., Kawecka A., Krzyściak P., Kucharek M., Bębenek Z., Zimowska M.

• Furcellaran nanocomposite films were prepared by solvent casting method. • Functional properties of FUR + AgNPs, FUR + GO and FUR + MWCNTs films were compared. • AgNPs were synthesized in situ within the FUR matrix. • Nanofillers influenced structural, physical and thermal properties of FUR films. • Antimicrobial and antifungal activity of FUR + AgNPs films were characterized. Graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) were added to furcellaran films (FUR). Silver nanoparticles (AgNPs) were prepared by reducing AgNO 3 using a FUR matrix as the stabilising agent. The structure and surface morphology of nanocomposite films were obtained using FTIR, SEM and XRD. The molecular weights of furcellaran chains were estimated using HPSEC-MALLS-RI. Characterisation of the films was undertaken to analyse their physical, mechanical and structural properties. SEM analysis revealed that GO, MWCNTs and AgNPs were evenly distributed throughout the FUR surface. FUR + AgNP films showed antimicrobial activity against bacteria and fungi. P. aeruginosa , E. faecalis and S. aureus were the most affected with effective growth inhibition using the disc diffusion method. In the study, the effect of nanofillers on the structural, thermal, mechanical and antimicrobial properties of furcellaran films as potential materials for food packaging is presented.

Karabasz A., Bzowska M., Szczepanowicz K.

Polymeric nanomaterials have become a prominent area of research in the field of drug delivery. Their application in nanomedicine can improve bioavailability, pharmacokinetics, and, therefore, the effectiveness of various therapeutics or contrast agents. There are many studies for developing new polymeric nanocarriers; however, their clinical application is somewhat limited. In this review, we present new complex and multifunctional polymeric nanocarriers as promising and innovative diagnostic or therapeutic systems. Their multifunctionality, resulting from the unique chemical and biological properties of the polymers used, ensures better delivery, and a controlled, sequential release of many different therapeutics to the diseased tissue. We present a brief introduction of the classical formulation techniques and describe examples of multifunctional nanocarriers, whose biological assessment has been carried out at least in vitro. Most of them, however, also underwent evaluation in vivo on animal models. Selected polymeric nanocarriers were grouped depending on their medical application: anti-cancer drug nanocarriers, nanomaterials delivering compounds for cancer immunotherapy or regenerative medicine, components of vaccines nanomaterials used for topical application, and lifestyle diseases, ie, diabetes.

Klyndyuk A.I., Chizhova E.A., Kharytonau D.S., Medvedev D.A.

Development of new functional materials with improved characteristics for solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) is one of the most important tasks of modern materials science. High electrocatalytic activity in oxygen reduction reactions (ORR), chemical and thermomechanical compatibility with solid electrolytes, as well as stability at elevated temperatures are the most important requirements for cathode materials utilized in SOFCs. Layered oxygen-deficient double perovskites possess the complex of the above-mentioned properties, being one of the most promising cathode materials operating at intermediate temperatures. The present review summarizes the data available in the literature concerning crystal structure, thermal, electrotransport-related, and other functional properties (including electrochemical performance in ORR) of these materials. The main emphasis is placed on the state-of-art approaches to improving the functional characteristics of these complex oxides.