Self-assembled Transition Metal Coordination Frameworks of ...

2.4.2. M TT Cell Proliferation Assay (Principle)
Ligands
The MTT cell proliferation assay is based on the metabolic activities of viable
cells. In this assay, the yellow tetrazolium salt, MTT (3,4,5-dimethyl-2-thiazolyl)-2,5­
diphenyl-2,4-tetrazolium bromide) used is cleaved by the enzyme, succinate
dehydrogenase, present in the mitochondria of metabolically active cells into water
insoluble dark blue formazan crystals. Both the compound (drug)-treated and the
control cells are subjected to MTT assay. These intracellular formazan crystals can be
solubilized using isopropanol or other organic solvents. After it is solubilized, the
formazan formed can easily and
H3
rapidly be spectrophotometrically
Ha
quantified at 570
nm.
- m l || Bf s + H3 l /ks HH3
@J:l@ =° UUKD
MTT MTTtormazan
(Yellow) I=> 579 nm (Purple)
Scheme 2.7. Chemical reaction in the MTT assay that result in the formation of
formazan crystals.
2.4.3. Procedure
The procedure involved for the study involves the following steps.
~ Stock concentrations of the compounds were prepared in DMSO and stored at
-70 °C.
~ MCF-7 cells were seeded in separate 96-well plates (7000 cells/ well) in 10%
DMEM and incubated at 37 °C / 5% CO2 for 24 h.
~ Once the cells had attached, the existing medium was removed and the cells
were washed with PBS-EDTA solution.
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