Effects of heat and piperidine post-treatment incubations on pBR322 plasmid DNA degradation measured as % DNA plasmid relaxation (Form II) after exposure to uranyl acetate and ascorbate. (A) Representative gel illustrating reactions of UA (0.50 mM) and ascorbate (0.50 mM) with pBR322 DNA (0.2 mM DNA-P, 25.0 mM ACES, pH 7.4, 37 °C, 30 min) followed by post-treatment exposure to either water (30 min, RT) (left); water (30 min, 60 °C) (center); or 30 μM piperidine (30 min, 60 °C) (right). (B) Quantification of DNA degradation as % DNA migrating as Form II for post-treatment exposure to either water (30 min, RT) (open bars); water (30 min, 60 °C) (grey bars); or 30 μM piperidine (30 min, 60 °C) (black bars). Data represent mean ± SEM for n = 4–14 independent experiments. Statistical significance of the effect of ± heat or ± piperidine was determined by ANOVA (NS not significant, *p<0.05, **p<0.01, ****p<0.0001).