Phototoxicity in Reconstructed Human Epidermal (RhE) Models

August 24, 2016
The 3-D Phototoxicity assay uses  reconstructed human epidermal (RhE) tissue constructs to evaluate the dermal phototoxicity potential of a test material. Toxicity is determined by measuring cytotoxicity [based on the relative conversion of MTT (3-[4,5 – dimethylthiazol-2-yl] – 2,5 – diphenyltetrazolium bromide)] in cultures treated with the test material in the presence and absence of UVA light. An advantage of using 3-D tissues to evaluate phototoxicity potential is that, unlike the 96-well phototoxicity assay, test materials are applied topically. As such,  solids, undiluted...

3T3 Phototoxicity (OECD 432)

August 24, 2016
The 3T3 Neutral Red Uptake (NRU) Phototoxicity assay is a 96-well cytotoxicity-based assay that utilizes BALB/c 3T3 mouse fibroblasts to measure the concentration-dependent reduction in neutral red uptake by the cells after exposure to a test material in the presence and absence of UVA light. Duplicate 96-well plates containing a monolayer of 3T3 cells are exposed to serial dilutions of a test material. One of the plates is exposed to 5 J/cm2 of UVA while the other plate is kept...

MEM Elution

August 21, 2016
The MEM elution assay or elution test is an in vitro cytotoxicity assay designed to show the presence of toxic material eluted from a test sample as it affects L929 cells cultured in the presence of the extract. Extracts of test articles are applied to L929 cells.  After treatment, the cells are exposed to neutral red dye to differentiate between the viable and stressed or lysed cells.  The degree of irritancy is determined microscopically in the percentage of cells deformed and...