Alkaline versus Neutral Version of Comet Assay in Human Leukocytes Using 9 Compounds

We investigated the in vitro activity of 8 chemicals of pharmaceuticals and alimentary interest by using both the alkaline and the neutral version of the Comet assay (Single Cell Gel Electrophoresis, SCGE). Aspirin (ASA), eugenol, (EUG), paracetamol (PCM) quercitin (QRC) and saccarine (SAC) were chosen because contradictory results on their genotoxicity have been reported in literature. Beside these, four compounds known to induce a wide range of genotoxic effects were included: the aneuploigenic chemical colcemid (COLC), the DNA repair inhibitor caffeine (CAFF), and the crosslinking inducer methylglyoxal (MTGL). Bleomycin (BLM) was used as positive control. The SCG test showed a good reproducibility between replicated experiments and a good specificity. The contemporary use of the dual dye viability assay and the neutral version of the Comet assay has allowed a better evaluation of the possible mechanism of action of the tested compounds, with particular regard to cell toxicity, allowing to avoide false positive results