After centrifugation, the supernatant was
discarded; the DNA pellets were washed in 75% absolute
ethanol, and centrifuged at 13,000 g for 5 min. After air-drying,
the DNA pellet was re-suspended in TE buffer (10 mM Tris,
1mM EDTA, pH 8.0) and stored at -20 °C until analysis. The
DNA concentration and purity were estimated by
spectrophotometer (NanoVue, GE Healthcare UK limited,