Tese_Tânia Vieira.pdf - Ubi Thesis

Chapter III – Results and Discussion
Table 5 – Different nanoparticles and their concentrations to perform the cytotoxic assays.
Low
Nanoparticles
Identification
concentration
(µg/mL)
MIC (µg/mL)
High
concentration
(µg/mL)
1 Chitosan/dextran nanoparticles 20.0000 107.1000 428.6000
2
3
4
5
Chitosan/dextran nanoparticles with
AgNPs (NaBH 4)
Chitosan/dextran nanopartices with
AgNPs (C 6H 8O 6)
Chitosan/dextran nanoparticles with
AgNO 3 and NaBH 4
Chitosan/dextran nanoparticles with
AgNO 3 and C 6H 8O 6
0.3000 1.5000 6.0000
0,1875 3.0000 6.0000
1,6243 11.7500 42.5000
1,6243 23.5000 42.5000
6 AgNPs (NaBH 4) 2,5000 10.0000 40.0000
7 AgNPs (C 6H 8O 6) 2,5000 10.0000 40.0000
Cell adhesion and proliferation was observed by using an inverted light microscope after
24 and 48 h (figure 13 and 14). In the negative control (K - ) cells were viable, appearing with
stellate geometry and showing slender lamellar expansions that joined neighboring cells. In the
positive control (K + ), dead cells were seen with their spherical characteristic form. For the cells
in contact with the different concentrations of nanoparticles, no toxic effects were observed
when nanoparticles in low or MIC concentrations were put in contact with cells during 24 and 48
h. This can be depicted in figure 13, where cells were similar to that of the K + . For the high
concentrations of nanoparticles almost no toxic effects were obtained, except for the particles
presented in figure 14 A, 4 (Chitosan/dextran with AgNO 3 and with C 6 H 8 O 6 as reducing agent) and
5 (Chitosan/dextran with AgNO 3 and with NaBH 4 as reducing agent) that presented some dead
cells. In the figure 14 B are presented the results obtained for the cells in contact with the
supernatants obtained from the nanoparticles washing, in which some adhered cells and some
dead cells were observed, indicating some toxic effects on the cells, during the period of
exposure to the supernatants.
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