Cell Proliferation and Viability Assays for Drug Discovery

Reaction Biology offers several different cell viability and proliferation assays for early drug discovery. Cell proliferation assays are widely used and accepted in oncology drug discovery as an initial test for the therapeutic efficacy of anti-cancer agents.

For analysis of the impact of anti-cancer drugs, the most common cellular phenotypic assay is the 2D proliferation assay in which tumor cells are growing in suspension culture or as monolayers in cell culture plates. This assay allows the testing of large numbers of compounds in a fast and cost-efficient fashion. Due to its simplistic setup, the assay is generally regarded as a pretest to more sophisticated assays such as apoptosis or 3D soft agar assays, which are also available at Reaction Biology.

  • Please reach out to discuss long term exposure options beyond a 3 days compound incubation period.
  • Regular large cell panel screening is available with our ProLiFiler screening service.

160 cell lines

160 human tumor cell lines are available for cell proliferation and viability testing.

Cell lines that are not in our panel can be established according to the specific research needs of our customers.

Please inquire for a list of our cell lines.

Additional Information

Assay Description

Cell Proliferation Assay


Cells are grown in multi-well plates (A) and incubated with compound for 72-hours (B, C). The number of viable cells is determined with CellTiter-Glo based on the amount of ATP present (D).

Additional Readouts

Additional readouts for in-depth investigation of cell death are available:

Example Data

Example Data


A tyrosine kinase inhibitor and staurosporine were tested for proliferation inhibition of 12 cancer cell lines. 72 h after compound addition, live cells were quantified via CellTiter-Glo. IC50 values are expressed as a percentage of proliferation in the presence of solvent alone (100% = high control) compared with cells treated with 1E-5M staurosporine (0% = low control).

Drug Combination Testing

Combining drugs that affect synergistically-acting targets is a promising strategy for drug discovery.

Depending on the drugs’ effectiveness and their mechanisms of action, different approaches are being used to determine combinatorial drug effects.

At Reaction Biology, we can perform
(i) a one-sided approach, i.e., the concentration of one drug is set, and the concentration of the other drug changes or
(ii) a two-sided approach, i.e., both drugs are tested with several concentrations in a checkerboard matrix setup.

Combination testing is available for Cell Proliferation Assay, ProLiFiler, Soft Agar Assay, Migration Assay, and 3D Tumor Spheroid Assay.

Assay Details

Assay details for CellTiter-Glo readout.

Setup: IC50 value determination and single concentration testing. Free choice for screening of the cell lines of your choice or panel screening via ProLiFiler.

Controls: DMSO only treatment serve as high control. Staurosporine treatment (at 1x10-5M) serves as low control. In every project, testing of a standard reference compound is included in IC50 format.

Custom assay development: Custom-tailored assays can be performed. Cell lines that are not part of the list, can be established according to the client’s research needs.

Report: A detailed report including assay conditions, methodology, and comprehensive evaluation of data as well as raw data for each analysis will be provided.

Turnaround time for standard studies is about 3 weeks. Expedited scheduling and data delivery can be arranged prior to study commencement.

Compound Information: For CellTiter-Glo assays please download our detailed sample requirements and shipping instructions here. For compound requirements of additional assay formats, please inquire.

Screening facility: CellTiter-Glo assays are performed at our German site. Additional readout formats are performed at our US site.