An overview of the most common methods for assessing cell viability
Author(s): Mohammad Shokrzadeh and Mona Modanloo
Background and Purpose: Measuring the proliferation and survival of cells is very important when studying the influence of various substances on cells. In this respect, several methods have been standardized to assess cell viability. These assays include common methods such as Trypan blue colorimetric method rather than the more complex ones such as MTT or XTT. Each of these methods has some merits and demerits compared to others. Some factors such as cost, speed, sensitivity and the required equipment are involved in selecting the suitable procedure. Despite the simplicity and cost-effectiveness of cell morphology evaluation, the sensitivity of this method is not very high and it is not adequate for short-term effects of materials. Trypan blue method is a common practice in the assessment of cell viability due to damage to cell membrane. This method, like other methods depends on the integrity of the membrane (Lactate Dehydrogenase release and fluorescent assays), is ineffective where there is cell damage without membrane damage. Despite being highly accurate, cologenic, fluorescent and flow cytometry assays are expensive and laborious. MTT assay as a simple, robust, rapid and cost-effective method is able to simultaneously evaluate a large number of samples. XTT assay is newer and more sensitive than MTT method. But contrary to MTT, it is not suitable for all kinds of cells. Generally, MTT assay is widely used as a reliable method. The current study aims to provide an overview of the most common methods used to evaluate cell viability and also weigh up the pros and cons of each method.