1. In vitro tumor hypoxia imaging with fluorescent covalent organic frameworksTina Skorjanc, Dinesh Shetty, Damjan Makuc, Gregor Mali, Martina Bergant Marušič, Matjaz Valant, 2023, published scientific conference contribution abstract Abstract: Hypoxia refers to a condition where cells and tissues experience low, inadequate levels of O2. While healthy tissues are typically supplied with sufficient O2 (normoxia), cancerous tissues commonly face hypoxia due to the tumor’s extraordinarily high demand for oxygen. Various fluorescent small-molecule probes have been designed for selective detection of hypoxia in living cells, but few nanomaterials have been investigated for this type of bioimaging. Herein, we prepare a fluorescent covalent organic framework (COF) with β-ketoenamine linkages and post-synthetically modify it to conjugate hypoxia-sensitive nitroimidazole moieties
into its pores (NI-COF). Stacks of sheets in NI-COF observed under electron microscopy were exfoliated by ultrasonication, and dynamic light scattering measurements confirmed particle size of less than 200 nm. Thus-prepared material exhibited good stability in physiological conditions and low cytotoxicity in in vitro experiments. NI-COF also showed useful fluorescence properties with an emission peak at 490 nm (λex = 420 nm) at both neutral and mildly acidic pH levels that are characteristic of tumor tissues. Encouraged by the favorable properties of the material, we incubated HeLa cells pre-treated in either hypoxic or normoxic conditions with NI-COF. Fluorescence microscopy images demonstrated that the material was preferentially taken up by hypoxic cells, which showed higher fluorescence signal in their interior than cells cultured under normoxia conditions. It is anticipated that this study will stimulate further developments of COFs for imaging various biological conditions.
Keywords: hypoxia, fluorescence, covalent organic frameworks, imaging, tumor cells
Published in RUNG: 19.09.2023; Views: 64; Downloads: 0
 Link to file
This document has many files! More... |
2. |
3. Nitroreductase-sensitive fluorescent covalent organic framework for tumor hypoxia imaging in cellsTina Skorjanc, Dinesh Shetty, Sushil Kumar, Damjan Makuc, Gregor Mali, Janez Vovavšek, Martina Bergant Marušič, Matjaz Valant, 2023, original scientific article Keywords: covalent organic frameworks, imaging, hypoxia, fluorescence, cancer cells
Published in RUNG: 17.05.2023; Views: 393; Downloads: 6
 Full text (1,55 MB) |
4. Silica Coated Bi2Se3 Topological Insulator Nanoparticles: An Alternative Route to Retain Their Optical Properties and Make Them BiocompatibleBlaž Belec, Nina Kostevšek, Giullia Della Pelle, Sebastijan Nemec, Slavko Kralj, Martina Bergant Marušič, Sandra Gardonio, Mattia Fanttti, Matjaž Valant, 2023, original scientific article Keywords: topological insulator, bismuth selenide, photo-thermal material, biocompatibility, nanoparticles
Published in RUNG: 22.02.2023; Views: 646; Downloads: 0
This document has many files! More... |
5. |
6. |
7. |
8. Determination of biogenic amines formation by autochthonous lactic acid bacteria from ‘Refošk’ grapes using different analytical methodsJelena Topić, Lorena Butinar, Martina Bergant Marušič, Dorota Korte, Branka Mozetič Vodopivec, 2022, original scientific article Abstract: Different analytical methods were tested and optimized for the determination of four biogenic amines (BA) histamine, putrescine, cadaverine and tyramine produced by grape-associated lactic acid bacteria (LAB). Autochthonous LAB were isolated from ‘Refošk’ grapes belonging to Slovenian-Italian Karst region as they represent a potential pool of beneficial LAB starter bacteria for improving the typicality and quality of wine. Six isolated strains were screened by multiplex PCR, of which four strains were positive for BA-forming genes (MKBT-49, MKBT-282, MKBT-568, MKBT-570). The production of BA was evaluated by thin-layer chromatography (TLC), high-performance liquid chromatography coupled to diode array detection (HPLC-DAD) and enzymatic method. The HPLC-DAD results showed that strain MKBT-49 (tyrdc+) had high tyramine production (386.6 ± 0.14 mg/L), which was confirmed by TLC. The ability to produce putrescine was confirmed in strain MKBT-282 by PCR, HPLC-DAD (16.4 ± 1.72 mg/L), and TLC. Histamine-producing ability was detected in strain MKBT-570, with a concentration below the limit of detection of the HPLC-DAD (<0.2 mg/L), while the other two methods were not sensitive enough for confirmation. This study shows that the production of BA can detected in native LAB and that relatively simple method such as TLC can be used effectively for the initial screening.
Keywords: grapes, wine-like matrices, biogenic amines, autochthonous lactic acid bacteria, analytical methods
Published in RUNG: 03.01.2022; Views: 1145; Downloads: 6
Link to full text
This document has many files! More... |
9. In vitro toxicity of arsenic rich waters from an abandoned gold mine in northeast PortugalMaria do Rosário Costa, Doroteja Gošar, Marika Pinti, Adelaide Ferreira, Martina Bergant Marušič, 2021, original scientific article Keywords: arsenic, water contamination, cytotoxicity, genotoxicity, Caco-2 cells
Published in RUNG: 23.07.2021; Views: 1514; Downloads: 9
Link to full text
This document has many files! More... |
10. |
