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DNA Amplification for Forensic Analysts

Maximum 3" Stability

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Free energy, ∆G, can be used to measure the thermodynamic stability of the primer-binding site. The maximum ∆G value for the five bases from the 3' end is used for this calculation.

For primers shorter than 30 base pairs, ∆G is computed using the following equation:

∆G = ∆H – T · ∆S

H = enthalpy

S = entropy

T = the user-defined melting temperature or Tm

When ∆G is negative, the reaction is spontaneous. When choosing between various primer pairs, a lower ∆value is favorable.10, 13, 14

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