Assessment of drug carrier cytotoxicity: shouldn't the current standards be revised?

Second passage smooth muscle cells (SMCs) from the aorta tunica media of three rats were pooled together and seeded on a 24-well plate. The plate was incubated for four days, and the nutrient medium was replaced daily. Cell morphology was assessed by using an inverted optical microscope. In particular, the SMCs were observed focusing on assessing malformation, degeneration, sloughing, or lysis of the cultures. Observations were also made on MTT and live/dead assays. The data suggests that the current standards for assessing biomaterial cytotoxicity should include some quantitative assays.