Stefan Jurga

• Prof. Dr.
• Research Director at Adam Mickiewicz University in Poznań

The COVID-19 pandemic has stimulated the scientific world to intensify virus-related studies aimed at the development of quick and safe ways of detecting viruses in the human body, studying the virus-antibody and virus-cell interactions, and designing nanocarriers for targeted antiviral therapies. However, research on dangerous viruses can only be...

Low efficiency of anticancer drugs and their toxicity in normal tissues has motivated further study on safe and effective modern anticancer agents. In the presented study, the design and synthesis of a library of 14 fluorinated curcumin (F-CUR) derivatives and their F-CUR-BF2 adducts are presented. Chemical modifications of curcumin derivatives inc...

The COVID-19 pandemic has stimulated the scientific world to intensify virus-related studies, aimed at the development of quick and safe ways of detecting viruses in human body, studying the virus-antibody and virus-cell interactions, and designing nanocarriers for targeted antiviral therapies. However, research on dangerous viruses can only be per...

Self-assembling peptides can be used for the regeneration of severely damaged skin. They can act as scaffolds for skin cells and as a reservoir of active compounds, to accelerate scarless wound healing. To overcome repeated administration of peptides which accelerate healing, we report development of three new peptide biomaterials based on the RADA...

In recent years, intensive research has been carried out on the use of hydrogels obtained from natural polymers, mainly chitosan. These products are increasingly replacing solutions based on synthetic materials in medicine. This publication presents the results of studies on the sol-gel transition of chitosan solutions as the base material for the...

Core−shell nanocomposites comprising barium titanate, BaTiO3 (BTO), and poly(methyl methacrylate) (PMMA) chains grafted from its surface with varied grafting densities were prepared. BTO nanocrystals are high-k inorganic materials, and the obtained nanocomposites exhibit enhanced dielectric permittivity, as compared to neat PMMA, and a relatively l...

Two novel tribenzopyrazinoporphyrazines with peripheral 4-methoxyphenyl substituents were synthesized to evaluate the effect of the centrally coordinated transition metal cation (4-Mn 3+ or 5-Fe 3+) on their elec-trochemical properties. The obtained complexes were characterized by UV-vis spectrophotometry, mass spec-trometry, and NMR techniques. Th...

This work presents the synthesis and characterization of metal-free, zinc (II), and cobalt (II) porphyrins substituted with short PEG chains. The synthesized compounds were characterized by UV-Vis, ¹H and ¹³C NMR spectroscopy, and MALDI-TOF mass spectrometry. The origin of the absorption bands for tested compounds in the UV-Vis range was determined...

Due to the rapidly increasing problem of antibiotic resistance in recent years, the use of phthalocyanines as photosensitizers with their superior properties in photodynamic antimicrobial therapy (PACT) applications has become important. In this study, magnesium(II) 1,4,8,11,15,18,22,25-octakis(4-[4-butoxycarbonylphenoxy]butyloxy)phthalocyanine was...

We compared the activity enhancement effect of noble metal deposited on TiO2 in photocatalytic nitrogen oxides oxidation. Titanium dioxide was decorated with Ag, Au, Pt or Pd in the sol-gel process. Synthesized catalysts were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller measurement (BET), X-ray photoelectron spectroscopy (XPS),...

Multimodal nanomaterials have attracted much attention of scientists, in particular those working in the area of medicine. Thanks to their properties, they can be applied in therapy as well as in diagnostics permitting simultaneous treatment and imaging of various cancer diseases. Photothermal therapy (PTT) is one of the approaches in the cancer th...

F Nuclear Magnetic Resonance spin-lattice relaxation experiments have been performed for a series of ionic liquids including the same anion, bis(trifluoromethanesulfonyl)imide, and cations with alkyl chains of different lengths: triethylhexylammonium, triethyloctylammonium, decyltriethylammonium, dodecyltriethylammonium, decyltriethylammonium, and...

Lata 60. XX wieku odznaczyły się przełomowymi dokonaniami naukowymi. Po raz pierwszy wyizolowano informacyjny RNA oraz rozszyfrowano kod genetyczny, co zainicjowało rozwój biologii molekularnej. Pierwszy spacer człowieka na Księżycu rozpoczął nową erę w nauce o kosmosie. Po 60 latach od tamtych wydarzeń, możemy połączyć wiedzę z obu dziedzin w celu...

The aim of our work was the synthesis of ZnO nano- and microparticles and to study the effect of shapes and sizes on cytotoxicity towards normal and cancer cells and antibacterial activity toward two kinds of bacteria. We fabricated ZnO nano- and microparticles through facile chemical and physical routes. The crystal structure, morphology, textural...

Starch-based confectionery products were prepared using different types of sugar. In addition to using different sugar, starch was replaced with soy protein isolate (SPI) in some of the products. ¹H NMR spin-lattice relaxation experiments were performed for the collection of products in a broad frequency range from 4 KHz to 30 MHz to get insight in...

Measurement of the nitric oxide (NO) concentration in living cells in the physiological nanomolar range is crucial in understanding NO biochemical functions, as well as in characterizing the efficiency and kinetics of NO delivery by NO-releasing drugs. Here, we show that fluorescence correlation spectroscopy (FCS) is perfectly suited for these purp...

H spin-lattice relaxation experiments have been performed for a series of ionic liquids including bis(trifluoromethanesulfonyl)imide anion and cations of a varying alkyl chain length: triethylhexylammonium, triethyloctylammonium, decyltriethylammonium, dodecyltriethylammonium, triethyltetradecylammonium, and hexadecyltriethylammonium. The relaxatio...

The aim of our work was the synthesis of ZnO nano- and microparticles and to study the effect of shapes and sizes on cytotoxicity towards normal and cancer cells and antibacterial activity toward two kinds of bacteria. We fabricated ZnO nano- and microparticles through facile chemical and physical routes. The crystal structure, morphology, textural...

H and ¹⁹F spin-lattice relaxation experiments have been performed for a series of ionic liquids sharing the same anion: bis(trifluoromethanesulfonyl)imide but including cations of different alkyl chain lengths: butyltriethylammonium, triethyloctylammonium, dodecyltriethylammo-nium and hexadecyltriethylammonium. The studies have been carried out in...

“Western diet” containing high concentrations of sugar and fat consumed during pregnancy contributes to development of obesity and diabetes type 2 in offspring. To mimic effects of this diet in animals, a cafeteria (CAF) diet is used. We hypothesized that CAF diet given to rats before, and during pregnancy and lactation differently influences fat c...

H and ¹⁹F spin-lattice relaxation experiments have been performed for butyltriethylammonium bis(trifluoromethanesulfonyl)imide in the temperature range from 258 to 298 K and the frequency range from 10 kHz to 10 MHz. The results have thoroughly been analysed in terms of a relaxation model taking into account relaxation pathways associated with ¹H–¹...

Tissue engineering (TE) is a rapidly growing interdisciplinary field, which aims to restore or improve lost tissue function. Despite that TE was introduced more than 20 years ago, innovative and more sophisticated trends and technologies point to new challenges and development. Current challenges involve the demand for multifunctional bioscaffolds...

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease, causing motor neuron and skeletal muscle loss and death. One of the promising therapeutic approaches is stem cell graft application into the brain; however, an immune reaction against it creates serious limitations. This study aimed to research the efficiency of glial re...

W 2021 roku mija 100 lat od poznania kwasu rybonukleinowego oraz 60 lat od odkrycia informacyjnego (messenger) RNA i kodu genetycznego. Z okazji tego wyjątkowego jubileuszu pragniemy przypomnieć najważniejsze wydarzenia w historii kwasów nukleinowych, które doprowadziły do powyższych odkryć. Wspomniany początek nowej ery w nauce spowodowany izolacj...

“Western diet” containing high concentrations of sugar and fat consumed during pregnancy contributing to development of obesity and diabetes type 2 in offspring. To mimic effects of this diet, in animals cafeteria (CAF) diet is used. We hypothesis that CAF diet given to rats before, during pregnancy and lactation differently influence fat content,...

Background Lipid liquid crystalline nanoparticles (LLCNPs) emerge as a suitable system for drug and contrast agent delivery. In this regard due to their unique properties, they offer a solubility of a variety of active pharmaceutics with different polarities increasing their stability and the possibility of controlled delivery. Nevertheless, the mo...

This review presents the latest innovations and trends in the field of surface functionalization of various nanomaterials. The most recent protocols of smart materials fabrication as well as the main challenges which should be overcome in order to improve their final performance are discussed here. Particular attention has been paid to the properti...

The application of ionic liquids (ILs) has grown enormously, from their use as simple solvents, catalysts, media in separation science, or electrolytes to that as task-specific, tunable molecular machines with appropriate properties. A thorough understanding of these properties and structure–property relationships is needed to fully exploit their p...

The structural characterization of glass slides surface-modified with 3-azidopropyltrimethoxysilane and used for anchoring nucleic acids, resulting in the so-called DNA microarrays, is presented. Depending on the silanization conditions, the slides were found to show different oligonucleotide binding efficiency, thus, an attempt was made to correla...

The aim of the study was to establish the influence of a co-precipitation agent (i.e., NaOH–immediate precipitation; hexamethylenetetramine/urea–gradual precipitation and growth of nanostructures) on the properties and catalytic activity of as-synthesized Au-CeO2 nanocomposites. All catalysts were fully characterized with the use of XRD, nitrogen p...

In this work we refer the properties of water solution of ciprofloxacin confined in single wall carbon nanotubes. Ciprofloxacin is well-known antibiotic applied against Gram-positive and Gram-negative bacteria. We study the influence of the size of nanotubes and their structure on interactions with the drug water solution. Analysis of Raman spectro...

Iron–platinum (Fe–Pt) compounds are well known for their interesting magnetic and electrocatalytic properties. However, iron segregation and iron oxides formation under oxidative conditions may influence the characteristics of Fe–Pt systems. Several approaches are used to protect the Fe–Pt compounds from oxidation, the most promising of which invol...

This work aimed to study for the first time to our knowledge the influence of the structure of the dental flosses (DF) coated by hydroxyapatite nanoparticles (HAP NPs) on the biological performance of saliva probiotic bacteria (S. salivarius), and human dermal and osteoblast-like cells. We used three types of [email protected] composites (based on...

Facile electrochemical graphite oxidation and functionalization with a selected array of amine moieties are carried out. The electrochemical oxidation offers the ability to preserve graphite morphological characteristics as intact adjacent surfaces yield collective van der Waals interactions. The different amine moieties are used to tether adjacent...

A progressive way in photodynamic therapy is to design photosensitive agents that may operate at lower optical power. Hybrid organic–inorganic silver-, iron-, and silver&iron-contained nanoparticles (NPs) were synthesized using H. perforatum extract and explored as photosensitizers for anticancer and antimicrobial photodynamic therapies at ultra-lo...

Photocatalytic hydrogen (H2) production on zinc sulfide (ZnS) still remains unsatisfactory because of the fast charge carrier recombination through direct-bandgap and photocorrosion by oxidative holes at the valence band. Here we report on a strongly coupled heterojunction photocatalyst (ZnS/PDA) comprising by a ZnS nanorod and ultrathin polydopami...

This book reviews a novel and exciting field of cellular and molecular biology called epitranscriptomics, which focuses on changes in an organism’s cells resulting from the posttranscriptional modification of cellular RNA. RNA-binding proteins (RBPs) play a crucial role in these posttranscriptional modifications and also support several cellular pro...

In this study, GNF@ZnO composites (gelatin nanofibers (GNF) with zinc oxide (ZnO) nanoparticles (NPs)) as a novel antibacterial agent were obtained using a wet chemistry approach. The physicochemical characterization of ZnO nanoparticles (NPs) and GNF@ZnO composites, as well as the evaluation of their antibacterial activity toward Gram-positive (St...

Studies revolving around mechanisms responsible for the development of amyloid-based diseases lay the foundations for the recognition of molecular targets of future to-be-developed treatments. However, the vast number of peptides and proteins known to be responsible for fibril formation, combined with their complexity and complexity of their intera...

A new mechanism of RNA circularization driven by specific binding of miRNAs is described. We identified the 71 CUUCC pentanucleotide motifs distributed regularly throughout the entire molecule of CDR1as RNA that bind to 71 miRNAs through their seed sequence GGAAG. The sequential binding of miR-7 RNAs (71 molecules) brings both ends of CDR1as RNA (1...

Introduction We present a multimodal nanoplatforms for the treatment of hepatocellular carcinoma (HCC) in vitro. The nanoplatforms are based on polydopamine (PDA)-coated magnetite nanoparticles (NPs) and spheres (sMAG) with PAMAM dendrimers and functionalized with NHS-PEG-Mal (N-hydroxysuccinimide–polyethylene glycol–maleimide) linker, which allows...

Alkylation reaction of dimercaptomaleonitrile disodium salt with N-(2-bromoethyl)phthalimide in N,N-dimethylformamide, and potassium carbonate led to novel maleonitrile derivative. This compound was used in the Linstead tetramerization reaction in n-butanol in the presence of magnesium n-butoxide towards magnesium(II) sulfanyl porphyrazine with pht...

Introduction AT101, the R-(-)-enantiomer of the cottonseed-derived polyphenol gossypol, is a promising drug in glioblastoma multiforme (GBM) therapy due to its ability to trigger autophagic cell death but also to facilitate apoptosis in tumor cells. It does have some limitations such as poor solubility in water-based media and consequent low bioava...

Polydopamine (PDA) has a wide range of applications in biomedicine due to its high biocompatibility and surface chemistry and because of the presence of many functional groups in it, enabling further modification. As a catechol-like material, it has chelation properties for various types of metal ions, including iron. Here, we developed a procedure...

In this work, we show synthesis that leads to thermoreponsive poly-N-isopropyl acrylamide (pNIPAM) nanogels with sizes below 100 nm, irrespectively of the surfactant to crosslinker ratio. We also show that in many environments the temperature induced pNIPAM collapse at Lower Critical Solution Temperature (LCST) of 32.5°C is accompanied by gel nanop...

Although less attention was paid to understanding physical localization changes in cell nuclei recently, depicting chromatin interaction maps is a topic of high interest. Here, we focused on defining extensive physical changes in chromatin organization in the process of skeletal myoblast differentiation. Based on RNA profiling data and 3D imaging o...

In response to the rapid development of nanomaterials in the biomedical field, especially in advanced cancer therapy, more comprehensive studies regarding the safety of nanomaterials are continuously required. Currently, several fundamental studies concerning the fate of nanoparticles in the biological media are needed, especially before in vivo st...

Poly(amidoamine) (PAMAM)-based electrolytes are prepared by dissolving the PAMAM half-generations G1.5 or G2.5 in propylene carbonate (PC), either with lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) or sodium bis(trifluoromethylsulfonyl)imide (NaTFSI) salts. The solutions, designed for ion battery applications, are studied in terms of ions tran...

Hypothesis Hydrogels of N-isopropylacrylamide and methacrylic acid (P(NIPAm-co-MAA)) display pH sensitivity and complex positively charged molecules through carboxylate groups, while having a critical solution temperature at which they reduce in volume and dehydrate. We aimed to elucidate how the responsiveness of MAA to environmental changes alter...

We have investigated the dispersion of the proton spin-lattice relaxation times in decylammonium chloride/water systems, which exhibit different liquid crystalline phases of isotropic (micelles), lamellar (layers), hexagonal (layers rolled up into cylinders), and of nematic structures. The measurements were performed in the frequency range from 3·1...

This work is the first report when multiharmonic analysis (MHA) was applied for electron paramagnetic resonance imaging (EPRI) for in vivo applications. Phantom studies were performed for established methodology, and in vivo imaging was conduct as a proof-of-concept. Phantom studies showed at least six times improvement of the signal – to – noise (...

Due to their capacity to conduct complex organic transformations, enzymes find extensive use in medical and industrial settings. Unfortunately, enzymes are limited by their poor stability when exposed to harsh non-native conditions. While a host of methods have been developed to stabilize enzymes in non-native conditions, recent research into the s...

An important subgroup within the porphyrazine (Pz) family constitute seco-porphyrazines, in the chemical structure of which one pyrrole unit is opened in the oxidative process. So far, there are only limited data on N-seco- and C-seco-Pzs. Here, the synthesis of a novel member of the Pzs seco-family, represented by an S-seco-tribenzoporphyrazine an...

The development of tissue scaffolds, which are able to provide proper and accelerate regeneration of tissue is a main task of tissue engineering. We developed a nanocomposite gel that may be used as injectable therapeutic scaffold. The nanocomposite gel is based on biocompatible gelling agents with embedded nanoparticles (iron oxide, silver, hydrox...

Infectious diseases constitute a serious problem for human health and life. Although many bacterial and fungal infections can be successfully cured by commonly used antibiotics, a new threat emerges in the form of microbial resistance. For this reason, researchers try to find not only new active pharmaceutical ingredients for conventional antibioth...

In this work the flower-like hierarchical structures (HS) based on 3D pristine ZnO, ZnO:Eu3+ and ZnO:Eu3+@Au were successfully obtained by a template-free solvothermal and deposition-precipitation method. The decolorization/photodegradation of these structures towards model organic dye (rhodamine 6G) was studied. The synthesized ZnO-based HS were c...

Composite coatings provide a promising way of in vitro cell behavior screening. Previous efforts included fabrication of single-walled carbon nanotubes (SWCNTs)-polymer materials, however in this work, for the first time we combined two polymers of different hydrophobic character: poly(maleic-alt-1-octadecene) and polyvinylpyrrolidone with multi-wa...

Chemical oxidation of graphite by strong oxidant in strong acid medium produces graphite oxide (GO) with a plausible oxidation degree, however the precursor is susceptible to exfoliation and structural deformations. In this work, we present a two-step preparation method of highly oxidized GO flakes with well-ordered layered structure. Firstly, grap...

ZnO (nano)structures remain of great interest in biomedical applications due to their unique properties and possible morphologies. Biocompatibility of typically fabricated ZnO structures remains questionable and they still lack desired biological functions, whence their functionalization is of high interest. In this work, we fabricated micro-sized...

The intensive development and commercialization of genetically modified plants observed over the last decade has led to the development of transgenic detection methods that are rapid and sensitive. Among the strategies used for the detection/monitoring of genetically modified organisms (GMOs), surface plasmon resonance (SPR) meets the necessary cri...

Many bacteria become progressively more resistant to antibiotics and it remains a challenging task to control their overall levels. Polymers combined with active biomolecules come to the forefront for the design of antibacterial materials that can address this encounter. In this work we investigated the photo-crosslinking approach of UV-sensitive b...

The transmembrane (TM) proteins are gateways for molecular transport across the cell membrane that are often selected as potential targets for drug design. The bilitranslocase (BTL) protein facilitates the uptake of various anions, such as bilirubin, from the blood into the liver cells. As previously established, there are four hydrophobic transmem...

The metallation reaction of 2-[2-(3,5-dibutoxycarbonylphenoxy)ethoxy]ethylsulfanyl-substituted porphyrazine with manganese and nickel salts led to novel porhyrazine derivatives with d-block metal ions in the core. Voltammetric studies of nickel(II) porphyrazine in organic electrolyte revealed the existence of well-defined one-electron ligand-based...

Evolution of bacteria to selective chemical pressure (e.g. antibiotics) is well studied in contrast to the influence of physical stressors. Here we show that instantaneous physical stress in a homogeneous environment (without concentration gradient) induces fast adaptation of Escherichia coli. We exposed E. coli to a large number of collisions of a...

It is already known that cells respond strongly to topography and chemistry of 2D surfaces. In this work we study cell‐material interactions; in particular, we investigated the attachment and alignment of SH‐SY5Y cells of neuronal origin on grooved‐patterns made from Silicon (Si) and Gold (Au). The Au‐Si groove pattern stimulated 93% of SH‐SY5Y cel...

Currently, an increase in the awareness of a healthy lifestyle has been observed in society. People are seeking added health benefits from their dietary intake. Thus, functional foods with supplemented components that promote wellness are becoming popular. Lycopene is a carotenoid that gives vegetables and fruits their red color. Due to its chemica...

A pressing challenge in engineering devices with topological insulators (TIs) is that electron transport is dominated by the bulk conductance, and so dissipationless surface states account for only a small fraction of the conductance. Enhancing the surface-to-volume ratio is a common method to enhance the relative contribution of such states. In th...

Background It has been shown that secondary metabolites occur in Chelidonium majus L. (C. majus) crude extract and milky sap (alkaloids such as berberine, coptisine, chelidonine, chelerythrine, sanguinarine, and protopine) are biologically active compounds with a wide spectrum of pharmacological functions. Berberine, an isoquinoline alkaloid extrac...

We investigated the influence of gadolinium (Gd)-based upconverting nanoparticles (UCNPs) on water spin–lattice relaxation (T1) and diffusion at different magnetic field strengths (0.4 T and 9.4 T). Our findings show that smaller NPs (12 nm compared to 19 nm) were more favourable for proton relaxivity. We also demonstrate that using simplified Solo...

Numerous glutamine analogues have been reported as irreversible inhibitors of the glucosamine-6-phosphate (GlcN-6-P) synthase in pathogenic Candida albicans in the last 3.5 decades. Among the reported inhibitors, the most effective N3-(4-methoxyfumaroyl)-l-2,3-diaminopropanoic acid (FMDP) has been extensively studied in order to develop its more ac...

Here we report on the structural and tribo-mechanical characterization of epitaxial single-crystalline Ti2AlC MAX phase thin films, grown by means of electron beam physical vapor deposition at relatively low temperature (700°C). The growth of phase pure Ti2AlC at a relatively lower temperature when compared to other PVD methods was achieved utilizi...

Nanocomposites based on block copolymer (BCP) and gold nanoparticles (NPs) filler were measured in terms of their structure and polymer chain molecular dynamics. NPs were functionalized in order to gain selective affinity to one specific type of BCP domain. BCP directed NPs assembly was monitored using atomic force microscopy. Thin nanocomposite fi...

Glioblastoma multiforme (GBM) is the most common type of malignant gliomas, characterized by genetic instability, intratumoral histopathological variability and unpredictable clinical behavior. Disappointing results in the treatment of gliomas with surgery, radiation and chemotherapy have fueled a search for new therapeutic targets and treatment mo...

In this review, significant applications of lanthanides and their compounds in bone tissue engineering are described, with an emphasis on coordination compounds based on wide variety of ligands, crystalline structure and their properties, stability as well as cytotoxicity. The current challenges and several scientific discoveries related to the use...