*2.6.* In Vitro *Assay for DNA Repair*

The *in vitro* repair assay is used to check the ability of cell extracts to carry out the first steps of BER. Gel-embedded nucleoids from HeLa cells carrying oxidized bases (substrate) were incubated with extracts from HeLa cells pre-incubated with/without vitamin C and with different concentrations of vitamin C directly.
