What factors affect the accuracy of cell viability assays?

There are various factors that affect the accuracy of cell viability assays. One factor is the assay method, as each assay utilizes distinct mechanisms to assess cell viability. For example, MTT assays are used to measure metabolic activity and Hoechst dyes are used in assays based on nucleic acid content. Different cell types exhibit variations in their sensitivities to viability assay reagents or techniques. Cell size, membrane characteristics, and shape all impact the accuracy of the assay. Experimental treatments such as drugs or environmental factors may affect the assay accuracy. Some treatments may interact directly with assay reagents resulting in interference and leading to incorrect results. Inadequate cell suspension, improper dilution, and clumping may all affect the distribution of cells and the homogeneity of the sample. Cells should also be incubated at proper conditions, as temperature, pH and humidity can affect cell proliferation and survival.