Cell proliferation lies at the core of growth, development, and tissue renewal. Likewise, cytotoxicity—the ability of a compound or condition to damage or kill cells—is a fundamental readout across drug screening, toxicology, and basic research. Together, these measurements form the backbone of modern biomedical research.

Depending on your lab setup, you may run these assays using

a multimode plate reader (chemiluminescence, absorbance, fluorescence),

a fluorescence microscope, or a flow cytometer.

Below, we break down the most commonly used assays, how they work, how to interpret results, and how to choose the right method for your experiment.

1. Overview of Common Cell Proliferation & Cytotoxicity Assays

Category	Assay / Method	Detection Principle	Detection Instrument / Notes
Chemiluminescence / Colorimetric Assays	MTT	Cell metabolism-based detection	Microplate reader
	CCK-8	Chemiluminescence / colorimetric assay	Microplate reader
	ATP assay	Cell viability via ATP quantification	Multifunctional microplate reader
	LDH assay	Cell cytotoxicity / membrane integrity	Microplate reader
	Total protein assay	Cell growth / proliferation	Microplate reader
Fluorescent Dye-Based Assays	BrdU	DNA synthesis detection	Fluorescence microscope / Flow cytometer
	EdU	DNA synthesis detection	Flow cytometer / Fluorescence microscope
	Live/dead staining	Viability assay	Fluorescence microscope / Flow cytometer
	Fluorescent cell tracking dyes	Live cell tracing	Fluorescence microscope / Cell imaging systems

 2. CCK-8 Assay

CCK-8 (WST-8–based) is one of the most widely used, rapid, and sensitive assays today.

Unlike MTT, its formazan product is water-soluble, enabling direct, non-destructive measurement at 450 nm. 

Figure 1. CCK-8 Reagent Kit Reaction Principle(Left) Relationship between absorbance and cell number in different cell lines

(●) 450 nm, CCK-8(Right)

Benefits:

• No crystal-dissolving step
• Higher sensitivity and wider dynamic range
• Minimal toxicity, cells remain intact
• High-throughput friendly

3. ATP-Based Cell Viability Assays

ATP assays rely on luciferase-driven bioluminescence, producing a light signal proportional to intracellular ATP content. Because ATP rapidly declines in dying cells, this method offers:

• Exceptional sensitivity
• Rapid readout (within minutes)
• Suitability for low cell numbers
• Outstanding linearity

Ideal for: HTS workflows, compound screening, low-density cultures.

Figure 2. ATP Luminescent detection principle diagram

4. Yeasen Cell Proliferation & Cytotoxicity Assays — Chemiluminescence Method

Product Selection Guide

Chemiluminescence-based assays offer rapid, sensitive, and high-throughput detection of cell proliferation and cytotoxicity. These assays are ideal for quantitative measurement of metabolic activity, ATP levels, or LDH release using a multifunctional plate reader. Select the appropriate kit based on your cell type, sensitivity requirement, and experimental goal:

Cat. No.	Product Name	Detection Sensitivity	Detection Time	Detection Indicator	Detection Wavelength	Cytotoxicity	Reagent Stability	Ease of Use
40206ES	MTT Cell Proliferation & Cytotoxicity Assay Kit	++	Relatively long	Dehydrogenase activity in mitochondria of live cells	A560–600 nm	High, cell morphology disappears	+	+
40203ES	Cell Counting Kit (CCK-8)	+++	Short	ATP	A420–480 nm	Low, cell morphology remains	+++++	++++
40211ES / 40212ES	ATP Cell Viability Assay Kit	+++++	Extremely short	Intracellular ATP	Chemiluminescence	Cells are lysed	++++	+++++
40209ES	Lactate Dehydrogenase (LDH) Cytotoxicity Assay Kit	+++	Short	LDH released into culture medium	A490 nm	Detects only supernatant	+++	++
40205ES	Sulforhodamine B (SRB) Cell Proliferation & Cytotoxicity Assay	+++	Relatively long	Intracellular basic amino acids	A515 nm	Cells need to be fixed	+++++	+++
40208ES	Trypan Blue Cell Viability Assay Kit	+++	Short	Dehydrogenase activity in mitochondria of live cells	A570 nm	Low, cell morphology remains	+++++	++