From:  Essential molecular biology methods in biomaterials research: a guide for emerging investigators

 Typical thermal cycling conditions

StepTemperatureTimeNotes
Initial denaturation94–98°C1–3 minLonger for hot-start enzymes
Denaturation (per cycle)94°C10–60 sMelts DNA strands
Annealing~Tm –5°C30 sDepending on the primer Tm
Extension70–75°C~1 min per 1–2 kb72°C is typical for Taq, 75°C for Pfu
Final extension72°C5 minEnsures complete product synthesis
Hold4°CIndefinitePreserves samples until retrieval