The anticancer potential of sixteen platinum(II) ternary complexes containing 8-hydroxyquinoline fragment. In vitro cytotoxicity was tested in human ?broblasts (MRC5), two carcinoma cell lines (A375 and A549) and embryotoxicity in zebrafish model. Interactions with double stranded DNA through in vitro assay and molecular docking study were examined. All complexes, (with one exception), exhibited high cytotoxic effect on MRC5 cells in concentration of 10 µg/mL and generally showed selective toxicity towards carcinoma cell lines in comparison to fibroblasts. In general, pta-based complexes were more toxic according to the results of MTT screen and LC50 values obtained in zebrafish (Danio rerio) assay and they also induced higher oxidative stress in this model. Successful cellular uptake of complexes was shown by ICP-MS methodology. The binding propensity of the complex with DNA, obtained in in silico studies can be correlated with those from the experimental investigation. From observations of DNA interaction ability and of the in silico assessment, no apparent DNA fragmentation was observed either on DNA extracted from the treated cancer cell line nor from the zebrafish embryos. This paper was already 20 times cited (Web of science search 30.4.20). We would like to mention that we have reported also other results in metal-hydroxyquinoline systems with anticancer activity. Most notable is paper on ruthenium complexes published in distinguished journal Inorganic chemistry: MITROVIĆ, Ana, KLJUN, Jakob, SOSIČ, Izidor, URŠIČ, Matija, MEDEN, Anton, GOBEC, Stanislav, KOS, Janko, TUREL, Iztok. Organoruthenated nitroxoline derivatives impair tumor cell invasion through inhibition of cathepsin B activity. Inorg. Chem., 58, 12334-12347 (2019), IF 4.850 [COBISS.SI-ID 4769905].
COBISS.SI-ID: 1537694915
Organoruthenium(II) complex with pyrithione (2-mercaptopyridine-N-oxide) has previously been identified by our group as a compound with promising anticancer potential without cytotoxicity on non-cancerous cells. To expand rather scarce research on these kind of compounds an array of novel chlorido and pta (1,3,5-triaza-7-phosphaadamantane) organoruthenium(II) complexes with methyl-substituted pyrithiones has been prepared. After thorough aqueous stability investigation further elucidation of complexes’ mechanisms on cellular level was performed. Minor structural alterations introduced to ruthenium-pyrithionato compounds resulted in fine-tuning of cytotoxicity. The best performing compounds with chlorido or pta ligand bound to ruthenium, respectively, and methyl on 3-position of pyrithione scaffold were further investigated. Both compounds trigger early apoptosis, induce ROS generation, G1 arrest in A549 cancer cells and show no strong interaction with DNA. However, only compound 1b does also inhibit thioredoxin reductase enzyme. Besides, wound healing assay and mitochondrial function evaluation reveal differences of both compounds at cellular level.
COBISS.SI-ID: 1538439875
Engineered solid-liquid interfaces will play an important role in the development of future energy storage and conversion (ESC) devices. In the present study, defective graphene oxide (GO) and reduced graphene oxide (rGO) structures were used as engineered interfaces to tune the selectivity and activity of Pt disk electrodes. GO was deposited on Pt electrodes via the Langmuir-Blodgett technique, which provided compact and uniform GO films, and these films were subsequently converted to rGO by thermal reduction. Electrochemical measurements revealed that both GO and rGO interfaces on Pt electrodes exhibit selectivity toward the oxygen reduction reaction (ORR), but they do not have an impact on the activity of the hydrogen oxidation reaction in acidic environments. Scanning transmission electron microscopy at atomic resolution (TEM), along with Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), revealed possible diffusion sites for H2 and O2 gas molecules and functional groups relevant to the selectivity and activity of these surfaces. Based on these insights, rGO interfaces are further demonstrated to exhibit enhanced activity for the ORR in nonaqueous environments and demonstrate the power of our ex situ engineering approach for the development of next-generation ESC devices.
COBISS.SI-ID: 1538365891
Vanadium(V) and zinc (II) compounds with 3,5-difluoropicolinic acid and 3-hydroxypicolinic acid, as well as zinc(II) complex with 4-methylhydroxypicolinic acid in the presence or absence of pyridine, 4-(dimethylamino)pyridine, and 1,10-phenanthroline have been synthesized and characterized. Structural characteristics were elucidated by X-ray crystallography and different spatial arrangements were observed. Insulin-mimetic activity of the selected V(IV)O, V(V)O2 and Zn(II) complexes was studied by in vitro inhibition of the free fatty acid (FFA) release from isolated rat adipocytes treated with epinephrine. All the studied metal complexes showed insulin-mimetic activity. Vanadium complexes exhibit activities similar to VOSO4 with the 3-hydroxypicolinato complexes being more active than the 3,5- difluoropicolinato ones. The zinc complexes also exhibited some insulin-mimetic activity, with the 3-hydroxypicolinato complex being more active than the others, however, the insulinmimetic activity of these complexes did not show more potent activity than ZnSO4. Research was conducted in the collaboration with Prof. Dr. Hiroyuki Yasui (Kyoto Pharmaceutical University) who performed in vitro insulinomimetic studies. Results of this research were presented also on: invited Key-note lecture at the 22nd Slovenian chemical days 2016, at seven invited lectures at foreing universities in USA, China, Cambodia, Hungary, Slovakia, Czech Republic. Other results of this study were published in high ranking journal J. Med. Chem. 2019, 62, 654 in the collaboration with Prof. Dr. Eugenio Garribba (Universita di Sassari, Italy) monitoring the role of ligands in the uptake and reduction of vanadium(V) complexes in red blood cells.
COBISS.SI-ID: 1537712067
Zeolites have been technologically important materials on a global scale for many years, with ever new applications, in recent years also associated with maintaining a clean environment and sustainable production. Their structural characterization is an indispensable part of investigating these materials. In this respect, we have long been involved in research of these materials. An article published in a leading journal in this field (Microporous and Mesoporous Materials) is an example of good practice where the results were obtained through the synergy of collaboration between a number of researchers using X-ray powder diffraction, Raman and FTIR spectroscopy, NMR in solid state, electron microscopy, elemental and thermogravimetric analysis. Two different quaternary ammonium cations, methyltriethyl- (MTEA) and tetraethylammonium cations (TEA) were used as templates in the synthesis of pure-silica as well as aluminosilicate ZSM-12 (MTW-type) frameworks. The distribution of the template cations in the 12-membered rings channels in the 1-dimensional framework topology was studied by means of all above metioned methods. It was shown that in pure-silica (PS) ZSM-12, TEA cations are well ordered - a superstructure with three-times longer b edge (in comparison to unit cell of empty framework) along the channel is formed, which can be seen by virtue of a few additional peaks in the X-ray powder pattern. We have observed that its aluminosilicate counterpart with TEA also contains ordered TEA cations and is isostructural to PS-ZSM-12. Conversely, in both pure-silica and aluminosilicate ZSM-12 frameworks with MTEA, the cations are disordered and no superstructure is formed.
COBISS.SI-ID: 6296346