Nanochemistry and biotechnology

The influence of GdVO4:Eu3+ nanoparticles on the adhesion properties and viability of rat hepatocytes in vitro

Kot Yu.1, Kot K.1, Ponomarov S.1, Klochkov V.2, Kavok N.2, Yefymova S.2, Malyukin Yu.2, Perskyi Ye.1 

1 V. N. Karazin Kharkiv National University, biochemistry department, 4 Svobody Sq., Kharkiv, 61022, Ukraine.
E-mail: kot.juriy@gmail.com
2 Institute for Scintillation Materials, Nanocrystal Materials Department, Nauky ave. 60, Kharkiv, 61072, Ukraine.

Spherical GdVO4:Eu3+ nanoparticles (D=3nm) with a highly active surface and an autofluorescence were synthesized in the Nanocrystal Materials Department of Institute for Scintillation Materials of National Academy of Sciences of Ukraine. These nanoparticles are promising in use as an indicator or modulator of cellular metabolism. Their effect on the growth pattern and viability of mammalian cells has not been studied yet.
The aim of the research was to study the effect of GdVO4:Eu3+ nanoparticles in different concentrations on the growth and viability of hepatocytes in vitro: the adhesiveness of the hepatocytes and their proliferative potential, the morphology and the number of apoptotic cells.
The studies were conducted on liver hepatocytes of 3-month-old Wistar rats with a viability of 87%. The obtained cells were incubated in a suspension of nanoparticles at concentrations of 0.75, 1.55, 3.10, 6.25, 12.5 μg/104 cells within 2 hours. Nanoparticles were washed off from cells. Cell culture was seeded and cultured for 15 days.
To assess the adhesive ability of cells, the number of attached cells was monitored 48 hours after seeding by using phase contrast microscopy. The proliferation assay of the cells was carried out on a culture growth curve. The assessment of total viability, morphology, and the number of apoptotic cells was analyzed on the 2, 5, 10 and 15th days of cultivation using phase and fluorescent microscopy and scanning fluorimetry.
Incubation with nanoparticles in all studied concentrations leaded to a decrease of adhesive ability of the cells. Reduction of cell adhesion occurred with an increase in the concentration of nanoparticles in the incubation medium. Depending on the concentration of nanoparticles, the formation of a monolayer of hepatocytes occurred on different days. Under the influence of nanoparticles at a concentration of 0.75, 1.55, 3.10 μg/104c cells, the monolayer formed on the day 8 after seeding, and at a concentration of 6.25, 12.5 μg/104 cells – on days 10 and 12, respectively.
Analysis of the exponential section of the hepatocyte culture growth curve shows the decline of the cell proliferation rate by the action of nanoparticles at concentrations of 6.25 and 12.5 μg/104 cells.
The total viability and average size of hepatocytes under the influence of the nanoparticles at concentrations of 0.75, 1.55, 3.10, 6.25 μg/104 cells, did not change during the observation time. Under the action of nanoparticles at the concentration of 12.5 μg/104 cells the viability decreased by 7% and the average size increased by 6.5 μm on the 15th day of observation. Also, under the action of nanoparticles at this concentration, the number of apoptotic cells increased by 39% on the 15th day of observation compared to cells without the action of nanoparticles.
Thus, in a view of the absence of negative influence of GdVO4:Eu3+ nanoparticles on the growth parameters and viability of hepatocytes, the concentration range of 0.75-3.10 μg/104 cells is the most optimal for further studies.