2.7.7. Antimalarial Assay (IC50 Determination)

The P. falciparum (0.8–1% parasitemia and 1% hematocrit) synchronous culture was exposed for 72 h (at 37 °C, 5% O₂, 5% CO₂, and 90% N₂) to the serially diluted compound in 96-well plates. A total of 100 µL of RBCs lytic buffer (5 mM EDTA, 20 mM Tris pH 7.5, 0.08% Triton X-100, and 0.008% Saponin) containing the SYBR green 1-X final concentration was distributed to each well and incubated for one hour at room temp in the dark. The plates were read under a fluorescence reader at an excitation of 485 ± 20 nm and emission of 535 ± 25 nm. The IC50 values were calculated based on the DNA content of the parasite relative to its control [26]. An inhibitory concentration of 50% (IC50) was determined using the MS-EXEL template. The signal-to-noise ratio was found to be 1:5–10.