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Generally a 10-50 mM Tris/HCl buffer with a pH above 8.0 (typically 8.3-8.8). KCl can be added to facilitate primer annealing, but shouldn’t be higher than 50 mM as this may inhibit polymerase. The deoxynucleotide triphosphates should have a total concentration of 0.4-1.0 mM, meaning each dNTP is present in an equal amount (100-250 pM). Magnesium is also required and should have a higher concentration than the total dNTP concentration (0.5-2.5 mM Mg²+). Magnesium affects primer annealing and template denaturation, as well as enzyme activity and fidelity. An excess of magnesium gives nonspecific amplification products, while low magnesium yields lesser amount of desired product.