Novel Arsenic Nanoparticles Are More Effective and Less Toxic than As (III) to Inhibit Extracellular and Intracellular Proliferation of Leishmania donovani

Figure 2

Impairment of oxygen consumption by As-NPs and As (III) treated Leishmania promastigotes. (a) The oxygen consumption by Leishmania promastigotes treated with 2 μM As-NPs for 24 (■), 48 (▲), and 72 (×) hours and those left untreated for 72 hours (◆) was measured by Gilson oxygraph as mentioned in Section 2. 1 × 10⁶ promastigotes were taken into the oxygraph cell and oxygen consumption was measured for 25 seconds. The average values for each set from three independent experiments were expressed as percent of the total oxygen dissolved. The data for the samples that were left untreated for 24 and 48 hours were the same as those of sample of 72 hours (not shown). (b) The oxygen consumption by Leishmania promastigotes treated with 20.0 μM As (III) for 24 (■), 48 (▲), and 72 (×) hours and those left untreated for 72 hours (◆) was measured by Gilson oxygraph as mentioned above. The percentage of oxygen consumed by these cells was graphically presented as done in panel (a) above. The “inset” shows the oxygen consumption by the parasites treated with 2.0 μM As (III) for the same time periods. The error bars indicate standard deviations in each data point in triplicate sets () of experiments. The values for each data point were calculated and found to be statistically significant (<0.05) (Table 1).

(a)

(b)