You can see some valuable opinions in these issue in the following link.

https://www.researchgate.net/post/Can_someone_advise_on_MTT_assay_blank_and_controls

I suggest other method since some reviewers are not longer accepting MTT to evaluate cell viability. See in attachment an interesting guidance of Cell Viability Assays

Thank you Alexander

You could perform annexin/propidium iodide staining or measure the release of LDH from the cells and express it as a % of the amount of LDH contained within extracts of cells that were not treated with the cytotoxic agent. Release of LDH by viable cells is low in healthy cells (< 5% of the amount contained within healthy cells).

Thank you Caroline for your valuable suggestion. Will check for LDH release in my formulation.