Liposomes and MTT cell viability assay: An incompatible affair

• Liposomes delivering drugs could produce inconsistent values of MTT absorbance.
• Empty-liposomes interfere, per se, on MTT assay by its lipidic nature.
• MTT assay may be inappropriated in studies involving liposome treatments.
• Additional method to evaluate cytotoxic effects should accompanied the in vitro MTT assay.

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay is commonly used to evaluate the cytotoxicity potential of drugs vehicled by liposomes. However, liposome delivering drugs could produce inconsistent values of MTT absorbance. On the basis of previous experiments demonstrating the MTT affinity for lipid droplets, this paper aims to show that empty-liposomes interfere, per se, on MTT assay due to its lipidic nature. This brings into question the use of MTT testing cytotoxicity when liposomes are involved in delivering drugs.