Ligita Mežaraupe

Ms. Ligita Mežaraupe


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 April 2021 in Biomolecules
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Journal Article
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IRIlze Rubenina
Ilze Rubenina
IGInese Gavarane
Inese Gavarane
EKElena Kirilova
Elena Kirilova
LMLigita Mežaraupe
Ligita Mežaraupe
MKMuza Kirjušina
Muza Kirjušina
Luminescent derivatives of benzanthrone are becoming more useful based on their light-absorbing and fluorescent-emitting properties. Our previous studies showed that luminescent staining properties of the same benzanthrone dye differ for variable parasite samples. Therefore, two types of benzanthrone dyes were prepared. One has a strongly basic amidine group and a halogen atom, and the other has an amide moiety and a tertiary amine group. Trematoda Parafasciolopsis fasciolaemorpha is a liver fluke of a moose (Alces alces) and has a significant influence on the health and abundance of the moose population. Staining protocols for parasite P. fasciolaemorpha specific organ or organ systems imaging are mostly time-consuming and labor-intensive. The study aimed to compare the fixation technique and the staining protocol by synthesized benzanthrone luminescent dyes to determine detailed morphology, anatomical arrangement of the organ systems and gross organization of the muscle layers of P. fasciolaemorpha using confocal laser scanning microscopy. Luminophores were tested for samples fixed in different fixatives. Developed dyes and staining protocol resulting in imaging of all parts of trematode without additional sample preparation procedures, which usually are required for parasite examination. Obtained results confirmed that the most qualitative results could be reached using 3-N-(2-piperidinylacetamido)benzanthrone dye which has amide moiety and a tertiary amine group. Based on obtained results, 3-N-(2-piperidinylacetamido)benzanthrone gave more qualitative parasite visualization than 2-bromo-3-N-(N′,N′-dimethylformamidino)benzanthrone.

4 March 2024 in Molecules
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Journal Article
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AMArmands Maļeckis
Armands Maļeckis
MCMarija Cvetinska
Marija Cvetinska
MKMuza Kirjušina
Muza Kirjušina
LMLigita Mežaraupe
Ligita Mežaraupe
SKSanita Kecko
Sanita Kecko
EKElena Kirilova
Elena Kirilova
In this research, we explore the synthesis of and characterize α-aminophosphonates derived from anthraquinone and benzanthrone, focusing on their fluorescence properties and potential applications in confocal laser scanning microscopy (CLSM). The synthesized compounds exhibit notable solvatochromic behavior, emitting fluorescence from green to red across various solvents. Spectroscopic analysis, including 1H-, 13C-, and 31P-NMR, FTIR, and mass spectrometry, confirms the chemical structures. The compounds’ toxicity is evaluated using etiolated wheat sprouts, revealing varying degrees of impact on growth and oxidative damage. Furthermore, the study introduces these α-aminophosphonates for CLSM imaging of the parasitic flatworm Opisthorchis felineus, demonstrating their potential in visualizing biological specimens. Additionally, an X-ray crystallographic study of an anthraquinone α-aminophosphonate provides valuable structural insights.

Verified
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IKInese Kokina
Inese Kokina
IPIlona Plaksenkova
Ilona Plaksenkova
LJLauris Jankovskis
Lauris Jankovskis
MJMarija Jermaļonoka
Marija Jermaļonoka
PKPatryk Krzeminski
Patryk Krzeminski
Marta KutwinMarta Kutwin
Marta Kutwin
Gold (Au) and silver (Ag) nanoparticles (NPs) are used for drug transport and plant protection due to their insoluble nature and unique properties. To produce health-friendly NPs, toxic solvents should be replaced with plant-based synthesis. Plants, such as alfalfa (Medicago sativa L.), release biomolecules that reduce metal ions and form nanoclusters without free radicals, showing anti-inflammatory and antioxidant properties. In this study, callus cultures of two M. sativa genotypes, ‘Kometa’ and ‘La Bella Campagnola’, were exposed to two precursors (AgNO3 and HAuCl4) for 24 and 48 h to assess the feasibility of biological NP synthesis. Spectrophotometry showed significant (p ≤ 0.05) changes in light absorbance compared with the control. Dynamic light scattering and zeta potential measurements indicated a change in the composition of the liquid compared with the control. To improve image quality and obtain more accurate data, transmission electron microscopy (TEM) analysis was repeated, confirming the presence of quasi-spherical nanoparticles with diameters in the range of 5–25 nm for both AuNPs and AgNPs in the callus culture extracts of both genotypes. Nanoparticle Tracking Analysis demonstrated that the AgNPs and AuNPs from both genotypes displayed polydisperse size distributions, with a mean particle size ranging from 220 to 243 nm. Elemental analysis provided clear evidence that Ag and Au were present only in treated samples, confirming effective NP biosynthesis and excluding contamination. X-ray diffraction (XRD) analysis was performed to characterise the crystalline structure; however, due to the very small particle size (5–25 nm), no clear diffraction patterns could be obtained, as nanocrystals below ~20–30 nm typically produce signals below the detection limit of standard XRD instrumentation. The novelty of this research is the cost-effective, rapid biosynthesis of quasi-spherical AuNPs and AgNPs with diverse sizes and enhanced properties, making them more eco-friendly, less toxic, and suitable for antibacterial and anticancer studies.

19 November 2025 in Molecules
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Journal Article
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EKElena Kirilova
Elena Kirilova
AMArmands Maļeckis
Armands Maļeckis
MKMuza Kirjušina
Muza Kirjušina
LMLigita Mežaraupe
Ligita Mežaraupe
IRIlze Rubenina
Ilze Rubenina
SBSergey Belyakov
Sergey Belyakov
In this research, we studied the synthesis and characterization of a novel amidine derivative of benzoperimidine derived from 1-aminoanthraquinone, focusing on its emission properties and potential applications in confocal laser scanning microscopy. The synthesized compound exhibited pronounced solvatochromic behavior in various solvents. Spectroscopic analysis, including 1H-, 13C-, and mass spectrometry, confirmed the chemical structure. The structure of three compounds was also determined using X-ray diffraction analysis; this study revealed the structural features of these substances in the solid state. The compound’s antimicrobial activity was evaluated using the agar diffusion method with the bacterium Bacillus subtilis subsp. Spizizenii. Furthermore, the study introduces a dye designed for imaging of the parasitic flatworm Opisthorchis felineus, demonstrating its potential in visualizing biological specimens.

8 October 2026 in Chemosensors
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Journal Article
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LMLigita Mežaraupe
Ligita Mežaraupe
EREvita Romanovska-Dzalbe
Evita Romanovska-Dzalbe
SKSanita Kecko
Sanita Kecko
MKMuza Kirjušina
Muza Kirjušina
VPVeronika Pavlova
Veronika Pavlova
IRIlze Rubenina
Ilze Rubenina
Fluorescence imaging has emerged as a transformative tool in parasitological research, providing high-contrast visualization of complex morphologies often obscured in traditional bright-field microscopy. This review article synthesizes recent advancements in the application of polycyclic aromatic fluorophores, specifically benzanthrone and anthraquinone derivatives, for helminth imaging. It evaluates the critical interplay between chemical fixation strategies, such as ethanol-based protein precipitation, and optical clearing agents like ethanol–xylene and lactic acid to optimize tissue transparency for confocal laser scanning microscopy. Recent practical applications are examined across diverse taxa, demonstrating that the rational design of N-substituted sensors—including aminoamides and aminophosphonates—enables high-resolution characterization of muscular–tegumental systems and reproductive organs in under one hour. Key breakthroughs highlighted include the rapid sex determination of Trichinella larvae and the detailed resolution of the tripartite muscle framework in trematodes like Prosotocus confusus. These developments establish anthrone-based sensors as a robust, efficient alternative to conventional commercial kits, offering superior photostability and spectral tunability.