MTT Assay: Cell Viability & Cytotoxicity (38 chars)

MTT Assay for Determining Cell Viability and Cytotoxicity

Presented by: Ifra Ramzan

This slide introduces a widely used method in cell biology. It evaluates cell health, viability, and cytotoxicity based on the metabolic activity of living cells.

Introduction

• Widely used method in cell biology
• Evaluates cell health, viability, and cytotoxicity
• Based on metabolic activity of living cells

Source: MTT Assay for Determining Cell Viability and Cytotoxicity Author: Ifra Ramzan Date: December 15, 2025

The assay uses yellow MTT tetrazolium salt, reduced by mitochondrial dehydrogenases in living cells to purple formazan crystals. Only viable cells perform this conversion.

Principle of the Assay

• Uses yellow tetrazolium salt, MTT.
• Living cells contain mitochondrial dehydrogenases.
• Enzymes reduce MTT to purple formazan crystals.
• Only viable cells perform this conversion.

Source: Ifra Ramzan

The slide describes the MTT assay's key reaction, where yellow MTT tetrazolium salt is added to cells and remains yellow in inactive or dead cells, indicating viable mitochondrial activity. It is reduced to insoluble purple formazan crystals proportional to metabolically active cells, which are solubilized for absorbance measurement at 570 nm.

Key Reaction

Source: Ifra Ramzan | December 15, 2025

The slide provides a workflow overview of the MTT assay procedure with four steps: adding MTT reagent to cell cultures, incubating for formazan formation, solubilizing with SDS-HCl, and measuring absorbance via spectrophotometer. It presents these in a simple table format under "Step" and "Procedure" headers.

Procedure Overview

{ "headers": [ "Step", "Procedure" ], "rows": [ [ "Add MTT", "Add MTT reagent to cell cultures." ], [ "Incubate", "Incubate to allow formazan formation." ], [ "Solubilize", "Add solubilization solution (e.g., SDS-HCl)." ], [ "Measure", "Measure absorbance using spectrophotometer." ] ] }

Source: Ifra Ramzan

Absorbance is measured at 570 nm (500–600 nm range), with color intensity proportional to viable cells. Cytotoxicity is determined by comparing results to untreated controls.

Quantification and Measurement

• Absorbance measured at 570 nm (500–600 nm range)
• Color intensity proportional to viable cells
• Compare to untreated control for cytotoxicity

Source: Ifra Ramzan

The "Data Interpretation" slide outlines absorbance stats from a cell viability assay. It defines 100% control absorbance as baseline viable cells, 90% as low cytotoxicity with high absorbance, and 20% as high cytotoxicity with low absorbance.

Data Interpretation

• 100%: Control Absorbance

Baseline viable cells

• 90%: Low Cytotoxicity

High absorbance value

• 20%: High Cytotoxicity

Low absorbance effect Source: Ifra Ramzan | December 15, 2025

The "Applications" slide lists key uses of the technology. These include drug screening for therapeutics, toxicity testing of chemicals, assessing cell proliferation rates, and evaluating experimental treatment efficacy.

Applications

• Drug screening for potential therapeutics.
• Toxicity testing of chemical compounds.
• Assessing rates of cell proliferation.
• Evaluating efficacy of experimental treatments.

Source: MTT Assay for Determining Cell Viability and Cytotoxicity - Ifra Ramzan

This conclusion slide summarizes the MTT Assay as simple, reliable, and cost-effective, measuring metabolic activity as a proxy for cell viability. It highlights its widespread use in biological and pharmaceutical research, ending with "Thank You!"

Summary

MTT Assay:

• Simple, reliable, cost-effective.
• Measures metabolic activity as proxy for viability.
• Widely used in biological/pharmaceutical research.

Thank You!

Source: MTT Assay for Determining Cell Viability and Cytotoxicity | Ifra Ramzan | December 15, 2025